LEEA Foundation Certificate (Global) Workbook PDF

Summary

This document is a workbook for the LEEA Foundation Certificate (Global) course. It covers essential knowledge about legislation, regulations, and best practices in the lifting equipment industry. The workbook provides a foundation for further study in diploma qualifications.

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1 LEEA – Foundation Certificate (Global) – Step Notes Foundation Certificate (FOU) (Global) Workbook Lifting Equipment Engineers Association Lifting Standards Worldwide...

1 LEEA – Foundation Certificate (Global) – Step Notes Foundation Certificate (FOU) (Global) Workbook Lifting Equipment Engineers Association Lifting Standards Worldwide www.leeaint.com 1 © LEEA Academy – FOU – Workbook April 2022 – v.1 LEEA – Foundation Certificate (Global) – Course Workbook Welcome to the Foundation Certificate (Global) This Foundation Certificate training course provides the essential underpinning knowledge required for those wishing to continue their study for Diploma qualifications. There is a mandatory requirement to have successfully completed this Foundation Certificate before accessing LEEA’s Diploma qualifications. The core areas covered in this course are: Legislation, regulations, standards and best practice relating to lifting equipment Definitions Controlling risks Materials science Units of measure Basic machines Manufacturers verification Rating of lifting equipment Types of lifting equipment 2 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Legislation and Regulations In this section, we will explore the purpose of legislation and regulations in the lifting equipment industry. Legal frameworks establish a broad system of rules that govern and regulate decision making, agreements, laws etc. Health and Safety The responsibility for health and safety at work rests primarily on the shoulders of the employer, yet employees also have responsibilities under health and safety law. Employers have a moralresponsibility to ensure appropriate working conditions are provided and this is generally known as a ‘moral duty of care’. The consequences for employers failing to adequately manage the health and safety of their employees can have serious implications: Unsafe working conditions are likely to have an impact on production Loss of output leading to lowering of morale and motivation Loss of sales turnover and profitability Society and customer expectations of a company’s approach to managing safety – health and safety culture Negative PR would have a damaging effect on any business The financial cost from loss of output Fines, damages, legal costs, insurance etc. 3 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Common elements of legislation pertaining to lifting equipment, worldwide Previous versions of the LEEA Foundation Certificate training course focused on the UK legislative framework. All LEEA courses now build on these requirements to provide globally applicable and accepted industry-specific, best practice training. Throughout the world, there are numerous national legislative requirements concerning lifting equipment. For example, the legislative framework for health and safety in the UK is the Health and Safety at Work Act, which is the primary piece of legislation and is responsible for enforcing the act and a number of other acts relevant to the working environment. It also states that all staff should take reasonable care of themselves and others around them and for their safety. Other examples are Australia, where the model WHS Act forms the basis of the WHS Acts that have been implemented in most jurisdictions across Australia. In the USA, the Occupational Safety and Health Act of 1970 is the primary health and safety legislation. ▪ Legislation: a rule or directive made and maintained by an authority ▪ Regulations: there are many sets of regulations applying to health and safety. Some apply to all places of work and others are specific to industries, operations, substances , materials and premises NOTES: 4 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Standards Standards are a published specification that sets a common language and contains a technical specification or other precise criteria and is designed to be used consistently, as a rule, a guideline, or a definition. Standards are applied to many materials, products, methods, and services helping to make life simpler and increase the reliability and effectiveness of goods and services. Standards are designed for voluntary use and do not impose any regulations, but many have such recognition that compliance with them gives a presumption of conformity and as such a quasi-legal status. ISO standards are international standards used globally. BSI standards are a ‘national’ British standard. ASME are American standards. Creating Standards Standards are usually created by a collective of subject matter experts, who function together as a committee. Details of proposed standards are agreed upon, and a draft of the standard is released for anyone who has an interest in the standard to make comments about the contents. When the reviews have finished, the standard is published. The four stages of creating any standard are, therefore: 5 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Codes of Practice, LEEA COPSULE and Best Practice A Code of Practice is a set of written rules which explain how people working in a particular profession should behave, or a set of standards agreed on by a group of professionals who do a particular job. There are various types of Codes of Practice: ACoP (Approved Code of Practice) RCoP (Recommended Code of Practice) A trade or professional Code of Practice Technical publications Safety information sheets The Regulations which provide the detailed requirements in respect of the general duties set out in ‘Acts’ do not specify how employers and others should meet those requirements. This is the role of the Approved Codes of Practice (ACoPs). These detail how to comply with the legal requirements. Who issues ACoPs? ACoPs are issued by relevant authorities with the consent of a government minister and following consultation with stakeholders, such as trade associations. There are ACoPs accompanying some of the health and safety regulations and they have a particular significance beyond providing guidance on complying with regulations. Contravention of the advice in a code of practice is admissible in evidence to prove a breach of the statutory provisions as set out in statute law and its associated regulations. Although failure to comply with any provision of the code is not actually an offence, such a failure may be used in criminal proceedings as evidence that a person has contravened a to satisfy the court that he has complied with the regulation in some other way. 6 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Working in a safe environment and with equipment that has been maintained and tested is vitalin this industry. Notes: 7 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Industry Relevant Definitions Duty Holder This is a broad concept used to capture all types of modern working arrangements. The duty holder is the person responsible for the lifting equipment that they own and use. Usually, this is the employer or self-employed person. The obligations imposed by legislation apply to the duty holder. However, in many cases, the duty holder will not possess the necessary skills required to fulfil these obligations. It is therefore acceptable for them to delegate some or all of their obligationsto suitably qualified personnel or organisations. If they do so, then it is important to note that this does not absolve them of responsibility, it simply changes the nature of their accountability. A duty holder who delegates or sub-contracts their legal obligations becomes culpable for ensuring that those undertaking the tasks are suitably qualified, experienced, trained, equipped, etc. In short, they are competent for their task. This means that they must ensure that employees are assessed and properly trained and provided with the necessary equipment for their role. In terms of external organisations, the duty holder must have procedures in place for vetting their competency. Modern legislation places responsibilities on users and those in the supply chain. In terms of use ultimate responsibility lies with the duty holder (employer of persons using the equipment), but employees also have obligations, typically to use only use equipment for which they have been trained and in accordance with that training. In terms of supply, ultimate responsibility tends to lie with the manufacturer. However, importers and distributors also have legal obligations. The reason for placing such responsibilities on suppliers and users is to protect the health and safety of everyone exposed to lifting equipment and lifting operations by ensuring that they are properly designed, constructed, maintained, and used correctly. 8 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook If we consider what factors legislation may be required of the manufacturers to establish such levels of safety, we will need to include: Ensuring the product meets any, and all essential health and safety requirements Any necessary verification of the equipment Supplying the end-user with all necessary safety information Safety in use and during maintenance Information relating to any foreseeable hazards What about employers responsibilities? Of course, employers (persons responsible for controlling work equipment) also have an important part to play in ensuring the health and safety of their employees. Their duties include: ▪ Ensuring equipment complies with any essential health and safety requirements ▪ Ensuring equipment is maintained and regularly examined ▪ Providing equipment and systems that are safe and without risk to health ▪ Provide employees with the necessary information, instruction, training, and supervision ▪ Ensure equipment is correctly selected for the task What are the equipment manufacturers responsibilities? Equipment manufacturers must comply with all national supply legislation applicable. This legislation varies between countries worldwide, but their fundamental principles generally align to EN ISO 12100 – Safety of machinery. General principles for design. Risk assessment and risk reduction. The standard identifies the essential safety requirements that need to be considered by all manufacturers to overcome hazards in lifting equipment. Notes: 9 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook The LEEA Code of Practice (COPSULE) is designed and established upon the general principlesof the requirements of the duty holder and work equipment legislation. We will look at COPSULE in further detail later in this course. Competent Person The term ‘Competent Person’ has long been used in legislation. Current legislation uses it for a variety of duties to describe a person with the necessary knowledge, experience, training, skills and ability to perform the specific duty to which the requirement refers. There can therefore be several ‘Competent Persons’, each with their own duties and responsibilities, i.e. competent for the purpose. The Competent Person should have the maturity to seek such specialist advice and assistance as may be required to enable him/her to make necessary judgements and be a sound judge of the extent to which he/she can accept the supporting opinions of other specialists. For example, the competent person inspecting, maintaining, or examining lifting equipment must be able to certify with confidence whether it is free from defect and suitable in every way for the duty the equipment is required. 10 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Competency What can be considered as the most important elements of competency? Notes: 11 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Factor of Safety, Inspection and Lifting Equipment Inspection We will consider 3 levels of inspection during this course: 1. Pre-use Inspection 2. Interim Inspection 3. Thorough Examination Notes: 12 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Pre-use Inspection: The pre-use inspection is normally carried out by the user of the equipment prior to use. The user will visually check for any signs of obvious defect or damage that give cause for concern. If such an issue is found, the user must report their findings to the appropriate maintenance/inspection personnel for further investigation before the equipment is made available for service. Interim Inspection: The interim inspection (sometimes referred to as the ‘frequent inspection’) is determined by risk assessment as to how often, and to what extent the inspection is performed. This level of inspection normally focuses on critical components that may become problematic prior to the next periodic thorough examination. Thorough Examination: The thorough examination (sometimes referred to as the periodic, or thorough inspection) is a visual examination of lifting equipment that is carried out by a competent person. The examination should be performed carefully and critically, supplemented by testing and measurements required by the competent person to ascertain the equipment’s fitness for a further period of service. Question: Why is regularly inspecting the equipment important? (Select all that you feel apply) □ Ensure that the equipment is safe to continue in service for another period □ To ensure you are competent to use the equipment □ To note any repairs that need to be made □ Ensure the equipment is working correctly □ Ensure that the equipment is safe to use □ To familiarise yourself with the equipment 13 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Lifting Equipment Lifting Equipment: This is a generic term used to describe all types of lifting accessories and appliances. Lifting Accessory: Sometimes referred to as lifting gear, lifting tackle or rigging equipment, an accessory is defined as a piece of lifting equipment that is used to connect a load to the lifting appliance. In ‘supply’ legislation, the lifting accessory may be included as an integral part of the load and independently placed on the market. In some national user legislation, accessories that are incorporated into the load are deemed to be part of the load and therefore not subject to the national lifting equipment inspection legislation. However, they must still be considered in the lift planning, be of adequate strength and be found to be free from defects. In which case it is recommended that there is an inspection regime that is as robust as that required by the national lifting equipment legislation. Examples of lifting accessories would include: ▪ Shackles ▪ Spreader beams ▪ Chain slings Lifting Appliance: Sometimes referred to as a lifting device or machine. An appliance is a machine that can raise, lower, or suspend a load. This excludes ‘guided loads’ such as lifts and continuous mechanical handling devices such as conveyors. Examples of lifting appliances would include: ▪ Cranes ▪ Hoists ▪ Jacks Notes: 14 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Manufacturers This in any natural or legal person who designs and/or manufactures lifting equipment or partly completed lifting equipment and is responsible for the conformity of the equipment with the applicable legal requirements with a view to its being placed on the market, under his own name or trademark or for his own use. In the absence of a manufacturer as defined above, any natural or legal person who places the equipment on the market or puts it into service shall be considered a manufacturer. Manufacturer’s Certificate, Record of Test or Statement of Conformity Depending on the standard being used, the manufacturer will usually issue a manufacturer’s certificate, a record of test, or a statement of conformity confirming the verification of the equipment. This document serves as the manufacturer’s confirmation that any necessary manufacturing test or other product verification required by the standard has been carried out and states the working load limit. Unless a specific document is required by the national supply legislation, then this document is also known as the ‘birth certificate’ for the product and it should be retained as part of the lifting equipment records. Notes: 15 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Industry Relevant Definitions It is important to have clarity on key industry relevant definitions. Minimum Breaking (or The minimum breaking or failure load is the specified load (mass or Failure) Load force) below which the item of equipment does not fail either by fracture or distorting to such an extent that the load is released. Multipurpose Multipurpose equipment is any equipment designed to a standard Equipment specification to lift a variety of loads up to the marked SWL, i.e., used for general (multi) purposes, and not designed for one specific lifting application. Operative An Operative is a trained person using the equipment. Rated Capacity This is defined as the maximum gross load that the lifting appliance can lift in any given configuration; generally used for lifting appliances in the same way as Working Load Limit is used for lifting accessories. Proof or Test Load A proof or test load is a load (mass or force) applied by the Competent Person for the purpose of a test. This load appears on reports of thorough examination if a proof test has been made by the Competent Person in support of their examination and on test certificates. Note: Proof load tests are also done as part of the verification of new lifting equipment or following installation. Single Single purpose equipment is any equipment designed for and dedicated Purpose to lifting a specific load in a specified manner or working ina particular Equipment environment, i.e., used for a single purpose. Report of Test Report of test, previously known as ‘test certificate’, is a report issued by the competent person who did the test and details the specifics of the test. Test reports are not legal documents allowing the equipment to be used, except when used in support of legal documents such as the EC Declaration of Conformity, ManufacturersCertificate or Report of Thorough Inspection/Examination. Note: new equipment for European or British markets this will be an EC or UK declaration of conformity respectively, or for products placed on other markets a ‘manufacturers certificate’. For older equipment test certificates and certificates of test and thorough examination were used. Previously these were known as a ' birth certificate'. However, all lifting equipment is verified in some way and manufacturers may append the verification details to the declaration of conformity / manufacturers certificate or combine them in a single document. Verification Verification is the generic term used to describe the procedures adopted by the manufacturer or Competent Person to ensure that lifting equipment is to the required standard or specification, meets legal requirements and is safe to operate. This includes proof load tests, sample break tests, non-destructive tests, calculation, measurement and thorough examination. 16 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Report of a Thorough Examination A report of a thorough examination (also known as a report of thorough inspection or report of periodic inspection) is a report issued by the Competent Person giving the results of the thorough examination, which will detail the defects found or include a statement that the item is fit for continued use. Where the Competent Person has carried out a test as part of the inspection/examination, the report will also contain details of the test. Key Note 1: The report of thorough examination must be retained as part of the lifting equipment records. Key Note 2: In some cases, a reference to the test report appears as an appendix to the thorough examination. Notes: 17 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Question: Would a proof load test be used as part of a ‘thorough examination’ for lifting accessories? (Select one answer) □ Yes □ No NOTE: Safe (Specific application) Working Load (SWL) The safe working load or specific application load (SWL) is the maximum load (mass) as assessed by a Competent Person which an item of lifting equipment may raise, lower or suspend under the particular service conditions. The SWL is marked on the equipment and appears in statutory records. In some geographical regions, the word ‘safe’ is not used in the description but the requirement is the same, so instead of safe the phrase ‘specific application’ is used instead and the acronym SWL will be used throughout this handbook. Working Load Limit (WLL) The working load limit is the maximum load (mass) that an item of lifting equipment is designed to raise, lower or suspend. In some standards and documents WLL is referred to as ‘maximum SWL.’ This term is more generally used for lifting accessories, but lifting appliances are now commonly marked with a rated capacity. Notes: 18 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook WLL vs SWL Much confusion exists between the terms ‘SWL’, ‘working load limit’ and ‘rated capacity’. By way of explanation, working load limit or rated capacity is the load value assigned to the ‘maximum’ SWL under ideal conditions (by calculation) and in most cases, the working load limit or rated capacity and the SWL will be the same. However, depending upon the conditions of use, it may be necessary for the Competent Person to reduce this to a lower SWL, and it is in these cases that the working load limit or rated capacity and SWL will differ. Risk If the risk assessment of the application indicate that such reduction may be Assessment required, it is essential that the user declares this information at the time of ordering so that the correct SWL may be attributed to the equipment and documentation. In the absence of such a declaration, the manufacturer or supplier will assume that the application is suitable for equipment rated with the SWL equal to the working load limit. If the equipment is in service or the user has not declared this information to the manufacturer, then it is the user’s responsibility to determine and mark the appropriate SWL. Hazardous The conditions where it may be necessary to reduce the working load limit toa Duties lower SWL are HAZARDOUS DUTIES. Hazardous duties could, for example, be environmental conditions such as extremes of temperature, high windspeeds or lifting procedures such as a likelihood of shock loading or inaccuracy of weight. When such circumstances arise, it is essential that systems should be instituted to prevent normally rated equipment from being used to its full capacity. Key Whilst it is the responsibility of the user to take such steps, the following advice Considerations should be considered: ▪ For specific installations where the equipment is fixed permanently in position, the equipment may be marked with the reduced SWL for that specific duty ▪ For specific installations where the equipment is portable, the user should provide written instructions to the operative which include an instruction to use a normally rated piece of equipment (i.e. SWL = WLL) but of appropriately higher capacity thus achieving the same effective reduction ▪ For an industry or a definable section of an industry where the majority of tasks require equipment having a reduced working load, then all the equipment should have a reduced working load i.e. that corresponding to the most hazardous duty 19 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Controlling Risks Risks Before we delve into more detail, first we have to consider the factors that contribute to accidents / ill-health in the workplace. 20 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook NET RESULT (Risk) = Likelihood x Severity 21 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Risk Assessment Many workplace activities are inherently dangerous, or they may be given a combination of circumstances. However, no one expects to risk life and limb, or their physical or psychological health, as a consequence of going to work. There is, therefore, a moral duty on employers to take appropriate steps to ensure the safety and health of their employees, and others. Risk assessment is the main means by which this can be effectively planned. Commonly referred to as Job Safety Analysis, Job/Task or Job Safety Review, simply put, this is a careful examination of all potential hazards that could cause harm to people so that a decision can be made as to whether enough precautions are in place, or if further control (precaution) measures need to be established. It is therefore a requirement that the totality of the risks in the workplace have been identified and that a plan is in place to control these. Although slightly different from nation to nation, a common approach to managing risk features a 5-step approach. Step 1: Identify the Hazards This is the process of identifying all the hazards that exist in the workplace. You need to be aware of all the possible hazards, but it is the significant ones that are important. Step 2: Decide Who Might Be Harmed and How This is the process determining who may be at risk from the hazards – the groups of staff and others likely to be affected in the case of an incident involving the hazard. Step 3: Evaluate the Risks and Decide on Precautions This is the process of assessing the significance of the risks and what needs to be done toprotect people. Step 4: Record Your Findings and Implement Them The significant findings of the assessment must be recorded and kept. There should, then, be a record of all hazards, the risks that they present and what precautions are in place to protect people from harm. Step 5: Review your findings The way we work is constantly changing – as a result of new or modifications of existing equipment, building alterations, new procedures, new or modified products, etc. Sometimes systems and procedures get changed by the staff themselves. These all bring their own hazards, but new hazards can also arise in existing methods of work – the effects of stress are a recent example. It is important to continue to be vigilant about hazards and risks and to review workplace conditions regularly. How often is 'regularly' will depend on the extent of the risks and the degree of change. 22 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Question: When considering people at risk, you only include those carrying out particular activities. (Select one answer) □ True □ False Identifying the precautions (control measures) necessary The first priority for controlling any significant risk to health is to try to avoid or eliminate it completely, i.e. no further risk present. However, this is impossible in many situations, so a hierarchy of control measures is used. Following on from step 3 of our risk assessment process the hierarchy will determine the most effective approach to controlling the risks and the following guide is generally used for this purpose: Eliminate (e.g. through elimination or substitution) Reduce (e.g. time of exposure) Isolate (e.g. segregation, personnel/hazard, lock-out/tag-out etc.) Control (engineering and administrative controls, safe systems of work) PPE (personal protective equipment) Discipline (ensure everyone follows the control measures and procedures in place) 23 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook ▪ ▪ ▪ ▪ ▪ Monitor and Review The safe systems (risk assessment, JSA, JSR etc) need to be regularly monitored to ensure that they are effective. It is often the case that more can be done to further reduce the level of riskas identified through effective monitoring. Just because a system is effective, it does not mean it is having maximum effect. It must also be noted that whilst all personnel involved in work under any specific risk assessment must have received suitable and sufficient information, instruction, training and supervision, this also applies to the supervisory role of those personnel carrying out the monitoring of the safe systems of work in place. Manufacturing of Lifting Equipment ▪ ▪ ▪ ▪ Material Properties Lifting equipment requires a balance of physical and chemical properties to make it suitable for its purpose. 24 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook ▪ Strength: Strength is a measure of how well a material can resist being deformed from its original shape. Typically, metals are specified for their tensile strength or resistance to being pulled apart, but compressive strength is also a legitimate material property describing resistance to being squeezed Ductility: Ductility is a mechanical property that describes the extent to which solid materials can be plastically deformed under tensile stress without fracture Malleability: Malleability is similar to ductility, but it is a material’s ability to deform under compressive stress. A good example of this is the manufacture of wire for wire ropes Brittleness: Brittleness is the tendency of a material to fracture or fail upon the application of a relatively small amount of force, impact, or shock o Brittleness is the opposite of toughness Elasticity: The ability of a material to return to its original dimensions after the removal of stress. A good example of this is a spring 25 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Plasticity: The ability of a material to retain its new dimensions once the stress is removed. A good example of this is a stretched chain link Toughness: Toughness is the ability of a material to absorb energy and plastically deform without fracturing Hardness: Hardness is a measure of how resistant solid matter is to various kinds of permanent shape change when a compressive force is applied Corrosion: This is the electrochemical oxidation of metals in reaction with an oxidant such as oxygen. Rusting, the formation of iron oxides is a well-known example of electrochemical corrosion. This type of damage typically produces oxide(s) or salt(s) of the original metal 26 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook ▪ Notes: 27 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Metals Metals are the primary group of materials used for lifting equipment manufacture. Metal is made from metal ores, which have to be mined and processed to transform them into usable materials. Pure metals are usually blended with other metals to change their basic properties. A mixture of metals is known as an alloy. Ferrous: Include steel and pig iron (with a carbon content of a few percent) and alloys of iron with other metals such as molybdenum, chromium and nickel. Non – ferrous: Non-ferrous metal and its alloys do not contain iron in large amounts. The most common type is known as low carbon steel – relatively easy to machine and is quite tough. Inexpensive to produce. Iron and Steel Pure iron is soft and easily shaped. Pure iron is too soft for many lifting equipment uses. Iron from the blast furnace is an alloy of about 96% iron with carbon and some other impurities. It is hard but too brittle for most applications, therefore most iron from the blast furnace is converted into steel by removing some of the carbon within it. This is done by blowing oxygen into the molten metal which reacts with the carbon, in turn producing both carbon monoxide and carbon dioxide which escape from the molten metal. The amount of oxygen used depends on the amount of carbon content required in the finished steel. Carbon steels are produced in several types: ▪ Low carbon steel (MILD STEEL) ▪ Medium carbon steel (HIGHER TENSILE STEEL) ▪ High carbon steel (HIGH TENSILE STEEL) The quantity of carbon present will affect the tensile strength, with the form and distribution ofthe carbon affecting the mechanical properties. Typical amounts are 0.25% -0.33% for Higher Tensile Steel. Mild steel is considered of limited use in the manufacture of lifting gear, i.e. chains and fittings. It is however used to fabricated items, such as grabs, trolleys, spreaders etc. 28 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Higher tensile steel is used to manufacture chain and fittings, resulting in a product one- third stronger than mild steel and recognised by grade marks 4, 04 or M. High tensile steel has limited use in lifting equipment. The hard-wearing properties do however make it suitable for use in components such as wheel axles and gearboxes. Other metals (alloys) are often added, such as vanadium and chromium which change the physical properties of the steel, such as toughness, ductility, and hardness. Alloy steel is a mixture of two or more elements, one of which is a Alloy Steel metal (e.g. nickel, copper, titanium, chromium, vanadium etc.) which are added to improve the properties such as increased strength, ductility and toughness. The disadvantage of alloy steels compared with carbon steels is that they are usually more difficult to weld, form and machine. Alloys contain atoms of different sizes. These different sizes distort the regular arrangements of atoms. This makes it more difficult for the layers to slide over each other, so alloys are harder than the pure metal. An alloy used in lifting equipment such as wire rope sling securing Copper and its Alloys ferrules. It is also a good conductor of electricity, used in cables. It is also non-magnetic and corrosion-resistant. An alloy of copper and zinc. It has limited applications in lifting Brass equipment. An alloy of copper and tin. The range of alloys can contain anything Bronze up to 18% tin to give the desired properties. It is tough and ductile and has good resistance to corrosion. An alloy containing nickel and copper with small percentages of Monel Metal manganese and iron. Good mechanical properties and excellent corrosion resistance. Monel metal is easily welded (although this is very expensive) and therefore tends to be considered where steel gear cannot be used under any circumstances, such as acidic conditions. Aluminium Aluminium is very light (one third that of steel) and has good corrosion resistance. It has many uses in lifting equipment and its typical uses are jacks, jaw winch casings, hand chain hoist covers, and most notably, for ferrules for wire rope eyes. Mobile Lifting Frames and profiled runway beams are also manufactured from lightweight aluminium extrusions, e.g. light crane systems produced by many manufacturers. Stainless Steel This steel has a minimum of 12% chromium added to improve its corrosion resistance. 29 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Steel Grades Used in Lifting Equipment The history of material grades is rather complex. They are not in fact material grades but rather product grades. The origin is chain and the grade is the breaking strength of the chain expressed as ‘grade x chain diameter squared. It only works in imperial units so a 1” grade 40 chain broke at 40 x 1² = 40 tons. A ½ “grade 80 breaks at 80 x ½ ² = 20 tons. When chain went metric some companies started using letter grades to make the distinction. Others used an abbreviated number e.g. 4 instead of 40. Coincidentally the mean stress at failure when expressed in N/mm² is almost 10 x the breaking strength in tons derived from the above formula. So imperial grade 80 has a mean stress at failure of approximately 800 N/mm². The mean stress is now used to define the grade. So grade 40 became M or 4, 60 became S or 6 and 80 became T or 8. This has continued with grade 100 being V or 10. 30 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook There were a few variations along the way. The original BS grade 40 was used at a factor of safety of 5:1 and because of that, it could either be in the normalised condition or hardened and tempered. To make the distinction the mark 04 was used for normalised and 40 for hardened and tempered. Later the factor of safety was reduced to 4:1 so it had to be hardened and tempered and again to make the distinction, grade M was used. So all three have the same breaking strength but the heat treatment and rating varied. Once all grades of chain were hardened and tempered, the letters and numbers became interchangeable and expressed as M(4), S(6) and T(8). However, when we started the European standards programme in the late 1980s, we agreed to use the number grades for medium tolerance chain for chain slings and the letter grades for fine tolerance chain for hoists. At the same time, we started using the terms medium tolerance and fine tolerance. Previously chain for hoists was termed calibrated to make the distinction but in practice, all machine-made chain is calibrated as part of the manufacturing process, the distinction is one of accuracy. When applied to components other than chain, the grades are not defined strictly by stress levels, rather by being compatible with the same grade of chain so whilst the maximum stress levels may be of a similar order, it is the manufacturer who decides on most of the dimensions (within the confines of the dimensional envelope) and therefore the stress level. Hence ‘Kuplex’ can use the same components for grades 8 and 10. Notes: 31 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Basic Machines Types of Machines There are two categories when it comes to machines, these are: Simple machines Compound machines Simple machines A lever is an object that acts as a pivot point that multiplies the force that can be applied to another object. The wheel and axle is a rod attached to a wheel that can multiply an applied force. A pulley consists of a wheel on an axle with a rope running over the wheel. Pulleys are used to change the direction of an applied force. The inclined plane is a flat surface with ends at different heights. Inclined planes reduce the amount of force required to move an object. Wedges are triangular-shaped and used to separate, hold or lift an object. Screws are cylindrical shafts with grooves that pass through or move other objects through rotational force. Compound machines A collection of simple machines working together. Compound machines are the most common type of machine and do more complex work than individual simple machines. They perform more work and therefore offer a greater advantage than simple machines alone. Compound machines may consist of various and innumerable combinations of simple machines. For example, a mobile crane’s mechanisms would include levers (the jib/mast), pulleys (sheaves), screw (limit switch), wheel and axle (drive train wheels) etc. Lifting equipment is manufactured using multiple combinations of basic machines in order to carry out a particular task. Notes: 32 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Weight and Force (F) Although not strictly true, we will consider weight and force to be equal and expressed in the same units. In a lifting machine, a small weight or force is used to lift a larger weight or force. We call the force required to do the lifting, the effort. We call the force being lifted, the load. Simple machines provide mechanical advantages. They make our work easier by increasing the amount of work done with a certain amount of effort, or by decreasing the amount of effort required to do the same work. Question: Using the image above, calculate the turning point. (Select one answer) □ 0.5Nm □ 10.2Nm □ 2Nm □ 9.08Nm Notes: 33 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Mechanical Advantage (MA) When the force and effort in a machine are equal, a state of equilibrium exists. Any subsequent increase in effort will move the load. In more complicated machines, e.g. a hand chain hoist, the effort required to move a load is usually much smaller than the load. Their relationship is known as the Mechanical Advantage. The mechanical advantage allows the device to perform the taskfor which it was designed. Consider… Consider the Mechanical Advantage of a simple winch. By increasing the lines of cable between the winch and the vehicle being pulled, we can pull more than the working load limit of the winch. Example… ▪ 1t WLL winch and 1 line of cable = 1t Max. tow weight ▪ 1t WLL winch and 2 lines of cable = 2t Max. tow weight ▪ 1t WLL winch and 3 lines of cable = 3t Max. tow weight NOTE: this illustration does not consider friction. A chain hoist is operated by hand. An operator will pull down on one of the chain loops on one side of the chain. This will turn a pulley mechanism inside the chain hoist housing. When this pulley turns, it lifts up the end of the other chain, which usually has a hook on the end. By pulling down on one chain, the manual hoist is actually able to increase the mechanical work that is being done. This is caused by the gear ratio inside the manual chain hoist. Typically, the force exerted on the hand chain can be multiplied by the gearbox as much as 30 times. 34 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Having established that the relationship between of the load (W) to the effort (P) is the mechanical advantage, this is represented by a simple formula: So if we know the load that is to be lifted and the amount of effort that has to be applied to the machine in order to do so, we can calculate the mechanical advantage. Note: we do not use any particular units of measure for a mechanical advantage as this is a simple mathematical ratio. Question: Select from the options below which one is the correct Mechanical Advantage calculation if the load is 300kg and the Effort is 50kg. (Select one answer) □4 □6 □3 Velocity Ratio (VR) Are machines can move large loads by applying small amounts of force. Unfortunately, as we all know, you never get something for nothing and in order to move the load a short distance, it is necessary for the effort to travel a greater distance. Having established that the relationship between these movements is called the Velocity Ratio, this can be represented by the following formula: Velocity Ratio = Distance moved by effort ÷ Distance moved by load (or DME ÷ DML) Notes: 35 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Question: Select from the options below which one is the correct Velocity Ratio calculation if the distance moved by effort is 75m and the distance by load is 3m (Select one answer) □ 25 □ 30 □ 10 Efficiency (EFF) Are machines are designed to waste as little energy as possible. This means that as much of the input energy as possible should be transferred into useful energy stores. Efficiency indicates how good a machine is in transferring energy input to useful energy output. A very inefficient device will waste most of its input energy. A very efficient device will waste very little of its input energy. The following formula can be used to establish the relationship between the Mechanical Advantage and Velocity Ratio to establish the Efficiency of a machine: Efficiency = MA ÷ VR x 100% Question: Using your answers above, what is the Efficiency calculation? (Select one answer) □ 16 □ 24 □ 12 Notes: 36 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook ▪ ▪ ▪ Polymers and Natural Fibres Polymers There are two types of polymers: Natural Polymers: Such as shellac, wool, silk and natural rubber have been used for centuries. A variety of other natural polymers exist, such as cellulose, which is the main constituent of wood and paper. Synthetic Polymers: Are materials such as synthetic rubber, resin, nylon, polyvinyl chloride (PVC or vinyl), polypropylene, polyamide, polyester, high modulus polyethylene (HMPE) and others. Notes: 37 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Polymer products are lightweight which makes them ideal for moving around from job to job. The properties of polymers can be altered by introducing additives such as plasticisers and stabilisers. In the lifting equipment industry, polymers are commonly used for roundslings and flat webbing slings, ropes, gears, bushes and sheaves. Nylon compounds, often in association with latex and rubber, are also used to manufacture wear seals, pressure seals and oil seals. Natural Fibres Fibre rope slings are the traditional form of textile sling whose origins are recorded in the earliest history of lifting equipment. Although their use has declined in recent years in favour of the newer forms of textile slings, i.e. flat woven webbing slings and roundslings, they may still be found in general use throughout the industry. Natural fibres are produced from grasses and other leaves that are spun to form ropes. Fibre rope slings are produced from cut lengths of rope which are then hand spliced. Common natural fibres for rope slings include manila, hemp and sisal. Notes: 38 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Heat Treatment There are various reasons for carrying out heat treatment. Heat treatment is the process of heating and cooling metals to change their microstructure and to create the physical and mechanical characteristics that make metals desirable for specific applications. The temperatures metals are heated to, and the rate of cooling after heat treatment, attribute to a metal’s final properties and can: ▪ Increase the strength (hardening a material) ▪ Decrease the strength (soften a material) ▪ Complete or surface hardening of a material ▪ Toughen a material by tempering ▪ Relieve stresses in a material ▪ Anneal a material after cold working to soften it, or to refine its grain structure Although each of these processes bring about different results in metal, all of them involve three basic stages: heating, soaking, and cooling. These 3 stages are used accordingly by the manufacturers to gain their desired properties. Hardening and Tempering as being the most common form of Heat Treatment. Heat treatment of steel is normally a two-step process. 1) Hardening 2) Tempering Heat treatment can therefore change properties of materials, such as Toughness Brittleness Ductility 39 Hardness Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Stress and Strain It is unlikely that you will need to carry out stress calculations as a lifting equipment examiner. However, it is important to understand their effects on equipment being examined and tested. - LEEA Stress There are forces acting on lifting equipment when it is under loaded conditions. Strength is therefore an important mechanical property of any lifting equipment. It is related to how much force can be applied to the equipment before it eventually breaks. The load (force) applied to the equipment and its cross-sectional area is the resultant stress in the material. It is the stress which controls whether a material will fail. The stress is found by dividing the (load) force by the cross-sectional area. In simple terms, when calculating stress, a force is usually spread over a given area resulting in a pressure of magnitude force unit ÷ area unit. Strain When a load (force) is applied to lifting equipment, it will respond by changing its shape. This is known as strain. Take an elastic band for example. If you hold it at its ends in a relaxed state, it will show no signsof extension, but as you apply an opposing force to the elastic band between your hands, it willbegin to stretch. This extension of the elastic band is known as strain. 40 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook The Tensile Test The tensile test, also known as the tension test, is probably the most fundamental type of mechanical test you can perform on material. ▪ The Tensile Test This tensile test reveals a great amount of information about the material and quantifies the important properties of the material. ▪ Why is this test important? Lifting equipment examiners need to know these properties and how they are determined in order to understand various material specifications and relate these to their suitability for making lifting equipment. A standard size specimen of the material to be tested is machined to a predetermined size. The cross-section of the specimen is usually round, square or rectangular. For metals, a piece of sufficient thickness can be obtained so that it can be easily machined - a round specimen is commonly used. For sheet and plate stock, a flat specimen is usually used. From the tensile test, we can use the results to determine how a material will react under tensile loading. Typical properties revealed include the elastic limit, yield point, ultimate tensile strength and elongation/reduction in the cross-sectional area of the material under test. A tensile load is applied to the specimen until it fractures. During the test, the load required to make a certain elongation on the material is recorded. A load/elongation curve is plotted by a recorder so that the tensile behaviour of the material can be obtained. 41 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook From a tensile test, a stress/strain, or sometimes known as a load/extension curve can be produced. Five definite points can be seen as the line of the graph: A. Limit of Proportionality B. Elastic Limit C. Yield Point D. Tensile Strength E. Ultimate Breaking Stress Question: What is meant by the term, ‘local necking’? (Select one answer) □ a. When a material under tensile load exceeds its maximum tensile strength, a reduction in material cross-sectional occurs which is known as local necking. □ b. When a material reaches its elastic limit, the measured reduction in cross-sectional area is called the local necking yield. Notes: 42 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Tensile Test Definitions: There are some key phrases/terms used regarding tensile test – see below: Limit of Initially as the force is applied the stress and strain are proportional Proportionality until point A is reached. This is the point at which the graph is no longer a straight line. This point is known as the Limit of Proportionality. The Elastic Limit This is the point up to which the material remains elastic. Within the elastic limit, the test piece will return to its original dimensions if the load is removed. (With mild steel this point practically corresponds with the Limit of Proportionality. This is not generally true of other materials or for materials that have been overstrained). When this point has been exceeded the extension is permanent and is referred to as Plastic Deformation. Yield Point Slightly above the elastic limit, the Yield Point is reached when a sudden permanent extension, B to C, occurs without any increase in load. (Sometimes there is a slight drop in the load, due to the extension, giving an upper and lower yield point). Tensile Strength The Tensile Strength is reached at this point. When this is passed the cross-sectional area becomes noticeably smaller and ‘necking’ occurs. This is the point of maximum load. Ultimate Breaking This is the actual breaking load where an increase in stress is obtained Stress with a reduction in load. Although the value is smaller than the tensile strength this gives a false impression of what occurred. From points D to E the section of the test piece considerably reduces as it ‘necks’ - thereby effectively increasing the stress. However, as the graph records the stress as load over the original cross-sectional area, it appears to decrease. There is a clear difference between a ductile material and a brittle material under the same tensile test. A brittle test piece withstands deformation until the stress applied is at a relatively high level. It then yields, deforms and fractures. A ductile test piece withstands deformation but yields at a lower level of stress than the brittle test piece. This is because the ductile material is not as strong as the brittle material. The ductile material then continues to elongate, reaching its maximum tensile stress and eventually fracturing. 43 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Shear, Tension and Compression Loading conditions: lifting equipment may be subjected to single or multiple types of stress: Single shear – forces acting across a material o Example: A lifting lug on a waste skip being lifted Double shear – forces acting across a material in two areas o Example: A shackle pin under load Compression – a pushing force o Example: A jack body under load Tension – a pulling force o Example: A chain sling under load 44 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Torsion – a twisting force o Example: A rotating gearbox shaft driving a hoisting appliance Notes: 45 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Units of Measure A unit of measure can be described as a standardised quantity of a physical property, used to determine multiple quantities of a given property. For example: Weight Length Mass Force Different systems of units are based on different choices of a set of fundamental units. The most widely used system of units is the International System of Units, or ‘SI’. There are seven SI base units. All other SI units can be derived from these base units. Under the SI system when marking lifting equipment only one decimal point is used for fractions of a tonne e.g. 2.1t, apart from when marking 0.25 which is always to two decimal places, e.g. 2.1t, 2.2t, 2.25t, 2.3t, 2.4t, 2.5t, 2.6t, 2.7t, 2.8t, 2.9t Notes: 46 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Question: Let's check your understanding of symbols relating to units of measure. From the list below, select which one you think matches the symbol of 'cwt'. (Select one answer) □ Pound □ Hundredweight □ Imperial or US Ton □ Metric tonne □ Kilograms NOTE: Question: From the list below, select which one you think matches the symbol of ‘T’. (Select one answer) □ Imperial or US Ton □ Hundredweight □ Kilograms □ Metric tonne □ Pound NOTE: Symbols and Conversions Ton (US) T = Imperial or US Ton 1 Ton (US) = 2000lbs = 907.185kg = 0.907t (metric) (commonly referred to as the ‘short Ton’) 1 tonne (Metric) t = Metric tonne 1 tonne (metric) = 1000kg = 2204.62lbs (rounded to 2204lbs) 1 Ton (Imperial) kg = Kilogrammes 1 Ton (imperial) = 1016kg = 2239.9lbs (rounded to 2240lbs) (‘long Ton’ in the USA) 1 cwt cwt = Hundredweight 1 cwt = 50kg The hundredweight was established in the imperial measurement system in which 1 Ton is divided into 20 subdivisions, each being a hundredweight. Occasionally, lifting accessories may be found in service today with a marked safe working load or working load limit of ‘cwt’. 1 hundredweight (cwt) = 50 kg, therefore, a marked load limit of 2 Ton 1 cwt = 2050kg, rounded down to 2t. 47 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook ▪ 1kg = 2.2lbs ▪ 1 inch = 25.4mm ▪ 1 foot = 12 inches ▪ The SWL of new equipment will normally be in the metric units of tonnes (t) or kilograms (kg) or imperial units of Tons (T) and Pounds (lb). The generally accepted rule is that a SWL of less than one tonne or Ton are marked in kilograms or pounds, respectively. Notes: 48 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Types of Verification New equipment should comply with the essential health and safety requirements stipulated in any applicable legislation, product standard where available, and issued with the required conformity documentation. This documentation is often combined with the results of the verification and together they form the ‘birth certificate’ which is an important legal document. New Equipment For new equipment, the verification methods used by the manufacturer will depend on the standard being worked to. Some equipment is unsuitable for proof load testing due to the nature of the materials used, e.g., textile slings. Some items are assembled from components verifiedto their own standards so no further tests are required, e.g., grade 8 mechanically assembled chain slings. Once in service, the verification methods used will be those deemed necessary by the Competent Person in reaching their conclusions about fitness for purpose. Types of Verification There are many types of verification and test available to the examiner, including: 49 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Test Machines and Force/Load Measuring Equipment Many of the product standards and codes of practice that require the application of a load, or force, lay down the accuracy to which the test load or force must comply. For example, BS EN 818-1 for chain requires accuracy of ±1%. It requires that test machines and load cells be calibrated and verified by a competent person or authority, in accordance with ISO 7500-1 at intervals not exceeding 12 months. It also requires that the accuracy of the applied load/force must be within that required by the standard being worked to and, in all cases, within ±2% of the nominal load/force. ▪ ▪ 1.0 ▪ Grade 0.5 = ±0.5%, 1.0 = ±1% and 2.0 = ±2%. The certificate will also give the Lower Limit of Calibration. This will be expressed as a load or force, depending on the units in which the machine or device is calibrated. This is the minimum load/force that can be read from the display within the required accuracy. Test loads below this cannot be measured with this equipment. In some cases, there may also be a similar restriction on the upper limit. 50 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook The person performing any form of load test must be aware of the limitations for use imposed on the test machine, or load/force measuring equipment, and ensure that the accuracy of the applied load meets the requirements of the standard being worked to. LEEA Technical Requirements LEEA Technical Requirements requires that a procedure be in place for checking and verifying measuring devices at appropriate periods. For tapes and rules, it will probably only be necessary to regularly check them to ensure that they are undamaged. However, precision measuring equipment will require periodic verification. Crack Detection When dealing with general lifting equipment, usually only basic crack detection (such as dye penetrate or magnetic particle) is performed to examine welds. Trained operatives are required to perform the tests and interpret the results. The tests are relatively inexpensive, both in termsof the equipment and the labour necessary to perform the tests. For more detailed crack detection examinations, particularly on high-value items or where additional safety requirements require a higher degree of examination, other methods used are eddy current, radiography and ultrasonic. These are more expensive to perform and call for a high degree of training and skill to interpret the results. Notes: 51 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Dye Penetrant: Dye penetrant crack detection is used to locate cracks, porosity, and other defects that break the surface of a material and have enough volume to trap and hold the penetrant material. Liquid penetrant testing is used to inspect large areas very efficiently and will work on most nonporous materials. Magnetic Particle (MPI): common and easy to use method for the detection of surface cracks and laminations in ferrous/magnetic materials and is primarily used for crack detection. The specimen material is magnetized and if the material is sound, the magnetic flux is predominantly inside the material. If there is a surface-breaking flaw, the magnetic field is distorted, causing local magnetic flux leakage around the flaw. This leakage flux is displayed by covering the surface with very fine iron particles applied either dry or suspended in a liquid. MPIis considered much more accurate, effective, and efficient than inspections that use dye penetrants. MPI is excellent at detecting flaws on the surface of objects. Eddy Current: this test can accurately find tiny flaws (cracks, corrosion, erosion, material degradation and loss of thickness in a material) in materials using hi-tec software and detection equipment. Operators can identify anomalies on both the surface and sub-surface of a material with good levels of accuracy. It cannot however be used on materials that are non-conductive.It requires minimal set-up time and there is no requirement to use chemicals or radiation in the process. 52 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Ultrasonic: a transducer is moved over a material by the operator. This subjects the material to high-frequency sound waves; tiny cracks, hairline fissures, microscopic pockets will create an echo that is shown visually on the test machine. The benefits of UT include speed, reliability and versatility for use in the field. In addition, the results of particular tests can usually be recorded, allowing for comparisons to be made over a length of time (identifying signs of deterioration). It is now one of the most commonly used methods of NDT. Radiography: a hazardous form of NDT that is not so common now as it has been in the past. Operators can be exposed to dangerous doses of radiation and there are extremely specialist skills are required to use this equipment. The test monitors the varying transmission of ionising radiation through a material with the aid of photographic film or fluorescent screens to detect changes in density and thickness. It will locate internal and surface-breaking defects. Electromagnetic Wire Rope Examination: This is a fast method of detecting defects in long lengths of wire rope. The rope is passed through a magnetic field. Breaks and disturbances in the magnetic field are detected and a printout of the field is given. The test involves using an instrument to examine ferromagnetic wire rope products in which the magnetic flux and magnetic flux leakage methods are used. If properly applied, the magnetic flux method is capable of detecting the presence, location, and magnitude of metal loss from wear, broken wires, and corrosion, and the magnetic flux leakage method is capable of detecting the presence and location of flaws such as broken wires and corrosion pitting. 53 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Hardness: indentations are used to verify the hardness of lifting equipment following heat treatment, or where equipment is used in conditions that might affect the heat treatment. There are three basic methods: Vickers, Brinell and Rockwell. Brinell is the most common method used in the lifting equipment industry by manufacturers. The Brinell Test Impact: the impact test is normally carried out by manufacturers using one of two methods, Charpy, or Izod. The Charpy impact test, also known as the Charpy V-notch test, is a test that determines the amount of energy absorbed by a material during fracture. This absorbed energy is a measure of a given material's notch toughness and identifies the properties that material will exhibit when it experiences a shock loading that causes the specimen to immediately deform, fracture or rupture completely. A specimen of material is supported at its two ends on an anvil then struck on the opposite face to the notch of the swinging pendulum and broken as the pendulum swings through it. The height of the pendulum swing measures the amount of energy absorbed during fracture. Three specimens are tested at any one temperature. The Izod Impact test is similar to the Charpy test but in this test, the material is held vertically in a vice type jaw and is in a cantilever. Izod impact is defined as the kinetic energy needed to initiate fracture and continue the fracture until the specimen is broken. Izod specimens are notched to prevent deformation of the specimen upon impact. This test can be used as a quick and easy quality control check to determine if a material meets specific impact properties or to compare materials for general toughness. 54 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Bend: this is a simple and inexpensive qualitative test that deforms the test material at the midpoint causing a bend to form without actually breaking the specimen. The test can determine the ductility or resistance to fracture of a material. Generally, a bending test is performed on metals or metallic materials but can also be applied to any substance that can experience plastic deformation, such as polymers and plastics. The bend test is usually used for the testing of welds. The purpose of bend testing welds is to make sure that the weld has properly fused to the parent metal and that the weld itself does not contain any defects that may cause it to fail when it is subjected to bending. Marking Lifting Equipment: marking should be by suitable means, i.e. plate, metal tab, textile label, etc, permanently attached or by stamping directly into the equipment, preferably in a non- load bearing or low-stress area. Stamping into a stressed area may also be permissible provided that the mechanical properties of the component are not significantly impaired. Where applicable, the position and size of stamping should be as indicated in the relevant standard. When the means of marking can be lost, additional information should be used to convey this information. It is therefore recommended that the identification mark should also be put directly onto the equipment so that in the event of the original means of marking becoming detached, the identity is not lost, and the other information can be recovered from the related documentation. It may occasionally be necessary to re-mark lifting equipment, but care must be taken in doing so as stress raisers may be induced. Marking should therefore only be made on selected areas where detrimental effects are minimised, and the stamping should not be too sharp or excessively deep. Notes: 55 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Trigonometry of slinging and the effects of angles in sling legs Uniform and trigonometric load methods When multi-leg slings are used at angles, the load in the individual sling legs will increase as the angle of each leg to the vertical (included angle between the sling legs) becomes greater. There are currently many multi-leg slings in service which are marked with the rating expressed at the ‘included angle’ or range of angles, e.g. 0-90°. This is the angle between the legs of the sling, and it should be noted that the LEEA COPSULE no longer recommends this method, stating that best practice is to use the angle between the sling leg and the vertical. As many geographical regions will not yet have adopted this approach, we will reference both the ‘included angle’ and ‘angle to the vertical’ in this training course. It must however be noted that in some regions, the angle of the sling leg to the horizontal is also used (e.g. USA) and at specifically included angles of 60°, 90° and 120° (e.g. Australia). These will be visited in the regional versions of the Lifting Accessories Diploma (Australia) / (USA) training courses. Notes: 56 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook If a sling is to be used safely, allowance must be made for this angle and this is achieved by rating the sling in one of two ways. The two methods of rating are often known as the ‘uniform load method’ and the ‘trigonometric method’. The Uniform Load Method This is a simpler option. It has built-in safety advantages which allow only one working load limit up to an angle of 45° to the vertical (90° included angle) and a reduced working load limit at angles between 45° and 60° to the vertical (90° and 120° included angle). This is the recommended method that should be used for all multipurpose slings. The working load limits are obtained from the following: Single leg sling = 1.0 x WLL of a single leg Two leg sling 0-45° (included angle 0-90°) = 1.4 x WLL of a single leg Two leg sling 45°-60° (included angle 90° -120°) = 1.0 x WLL of a single leg Three and four-leg sling 0-45° (included angle 0-90°) = 2.1x WLL of a single leg Three and four-leg sling 45°-60° (included angle 90° -120°) = 1.5 x WLL of a single leg Standards where the uniform load method has been used, rate a multipurpose four-leg sling at the same working load limit as a three-leg sling of the same size and grade. This is on the assumption that the load might be taken by only three of the four legs. However, some national standards have now been amended such that they work on the assumption that the load may be carried by two of the legs. Note: Some standards do not recommend the rating of three leg slings at included angles greater than 90°. This is due to the danger of a user assuming that the ‘included angle’ referred to the angle between the legs of the sling instead of twice the angle of a leg to the vertical. Where slings are rated and marked on the basis of the angle to the vertical this danger does not exist. In Australia, the WLL of multi-leg slings comprising of more than two legs is limited to the same WLL as a two-leg sling. This is rated at an included angle of 60° between sling legs. Mode Factor The mode factor is a numerical value that is applied to the marked working load limit of the sling to determine the maximum load which the sling may lift, according to the mode of use and assembly, e.g. angle of sling legs to the vertical in use. 57 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook Calculating the Mode Factor The mode factor for various sling angles is derived from the cosine of the angle to the vertical. Question: The WLL of a single leg sling is 2t. If two of these identical slings are used together at an included angle of 0-45° to lift a load, what is the maximum load that the sling assembly may lift? (Select one answer) □ a. 4t □ b. 2.8t □ c. 1.4t □ d. 5.4t The Uniform Load Method Design Factors The following design factors should be applied to the WLL of a single leg to establish the WLL of multi-leg sling assemblies or where a number of single slings are being used in combination: 2 leg sling 0°- 45° to the vertical (or 0° - 90° included) 1.4 2 leg sling 45°- 60° to the vertical (or 90°-120° included) 1.0 3 and 4 leg sling 0° - 45° to the vertical (or 0° - 90° included) 2.1 3 and 4 leg sling 45° - 60° to the vertical (or 90°- 120° included) 1.5 58 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024 LEEA – Foundation Certificate (Global) – Course Workbook The Trigonometric Method The trigonometric method provides for a variation in the working load limit as the angle to the vertical (or the angle between the sling legs) varies. This method is the one that was previously used in many standards, but in order to use it for multipurpose applications, the operative must calculate the SWLs at various angles for each size of the chain, rope, etc. It also requires the operative to be trained in judging a range of angles and has the inherent danger that if he should misjudge these, the sling may well be overloaded. Although the uniform load method was introduced to some standard practices, some manufacturers continue to rate and mark multipurpose slings by the trigonometric method. Slings intended for multipurpose use marked this way will not comply with those standards that have adopted the uniform load method and it is strongly recommended that this method should be used only for slings designed for a single purpose or in accordance with the applicable national standards that permit it. Working load limits are obtained from the following: Single leg sling 1.0 x WLL of a single leg Two leg sling 2 x WLL of a single leg x cos β Three leg sling 3 x WLL of a single leg x cos β Four leg sling 4 x WLL of a single leg x cos β Rating of Slings The uniform load method simplifies matters by removing the need for tables and reducing the need for the operative to estimate angles. Whilst the uniform load method of rating is most easily applied to equipment such as multi-leg slings, it may, with advantage, also be applied to such items as eyebolts when used in pairs. Many national and international standards are now in favour of the uniform load method, largely on the grounds of safety and simplicity. However, this does not exclude the trigonometric method when working to national standards that allow it within their scope or with a justifiable reason to deviate from the uniform load method. 59

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