LEEA Foundation Certificate (Global) - Course Workbook PDF

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...

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 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Course Workbook Other forms of rating for lifting equipment Multi-Leg Slings (User Information): If a multi-leg sling is used with less than its actual number of legs attached to the load, then obviously the safe working load of the sling must be reduced.The amount by which it should be reduced can be calculated exactly but it is rather complex, as numerous factors need to be considered, including the method of rating. An easy way of ensuring that the sling is never overloaded is to reduce the safe working load from that marked on the sling according to the number of legs in use. The following ratings apply: ▪ A 4 leg sling with only 2 of the legs being used: ▪ A 3 leg sling with only 2 of the legs being used: Rating of Lifting Accessories Endless slings have fewer variations of use, but it should be remembered that the slinging factor for endless chain and wire rope slings assumes choke hitch, whereas the standard rating for textile slings assumes a straight pull. In all cases, it is also assumed that, at the points of attachment to both the lifting appliance and the load, the radius around which the sling passes are large enough to avoid damage to the sling. In the case of chain and wire rope endless slings, the rating takes account of the chain and wirerope being bent around itself on the bight. Rating of other types of lifting accessories will be detailed in the relevant modules within this, and further Diploma level LEEA courses. 60 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Course Workbook Wire Rope Slings Wire rope slings are very popular for general lifting duties. Due to their rigidity, they can be easily passed under loads when slinging. However, they are more susceptible to damage than chain slings. The construction of the rope from which the sling is made is within reason unimportant provided that the rope has adequate flexibility and an adequate minimum breaking load (from which the SWL of the sling is calculated). The rope should be ordinary lay and maybe six or eight strands having a fibre or a wire core. As with any lifting media, slings of all configurations can be assembled from wire rope and will be found in service. Those working in the offshore industry will be familiar with the ‘five leg’ slings attached to offshore containers. These are actually four-legged wire rope slings with a pendant sling attached to the master link. In general industry, the most common type of wire rope slingin service is the single leg. Thimbles: these are a protective insert that is fitted to the eye of a sling leg at the time of manufacture. Thimbles are fitted where it is desirable to protect the eye from the worst effectsof abrasion and point loading. Two common types of thimble are used in the construction of slings. The teardrop-shaped thimble, which is used where sling legs are to attach to other fittings, and the reeving thimble, is designed to permit the passage of one eye through the other so that the sling may be used in choke hitch. A similar protective inset, known as the stirrup or half thimble, is designed to protect the wire rope of a soft eye when the sling is used in choke hitch. Hand Spliced Eye: the hand spliced eye is an eye formed at the end of a sling by the traditional method of threading the individual strands of the rope back along the main body of the rope ina prescribed pattern. This type of eye is now less popular than the more modern ferrule secured eye, but it is still available and preferred by some users. 61 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Course Workbook Common Sling Assemblies: in addition to 2, 3 and 4 leg wire rope slings, the most commonly used wire rope sling assemblies are: Single leg with soft eye or thimble eye at each end. They can also be fitted with a link at one end and a hook at the other. 62 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Course Workbook Terminal Fittings Notes: 63 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Course Workbook Eye Terminations There are two ways that eyes can be made, ferrule secured (sometimes incorrectly referred to as a mechanical splice) and hand spliced. 1. Turn Back Loop The turn back loop is the cheaper option to manufacture and therefore is perhaps used more commonly for general purpose slings. With this method, an aluminium ferrule is used to secure the eye made in the end of the rope The eye is simply formed by passing the ferrule over the rope, bending the rope back on itselfto form the eye, pulling the ferrule back over the returning tail end of the rope and then pressing the ferrule. Under pressure the aluminium flows into the rope formation, making a homogeneous joint Ferrule Secured Eyes When square-cut ferrules are used, it is necessary for a small amount of the tail to protrude through the ferrule to ensure that the rope is fully engaged within the ferrule. The standard says that the length of this should be no more than one half of the rope diameter. However, if the rope has been cut by a heat process, a portion of the rope will have become annealed (softened) in the heat-affected area. The protruding tail in this case should be no more than an amount equal to one diameter of the rope and positioned so that none of the annealed section is within the ferrule Tapered Ferrules Tapered ferrules are also available from some manufacturers. In this case, the tail end remains within the ferrule and it is essential that the ferrule manufacturer’s instructions for fitting are followed. Often, the manufacturer of the ferrule will provide a small view hole in the ferrule to enable the tail end to be seen 64 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Course Workbook 2. Flemish Eye A tapered steel ferrule is passed over the rope. The standing part of the rope is then taken, and three strands are unravelled and opened so that a ‘Y’ formation is made. Care must be taken to ensure that the strands still lay together as they had in the rope The leg of the ‘Y’ that includes the core is bent to form an eye so that the ends of the strands sit against the undisturbed part of the rope at the bottom of the ‘Y’. The remaining three strands are then re-laid into the rope in the opposite direction, taking up the position they originally had inthe rope so that the lay of the strands is not disturbed The ends of the strands are then evenly distributed around the intact standing part of the ropeto complete the eye. The ferrule is then slid back over the distributed wires without displacingthe strands and then pressed. The ferrule compresses and grips the rope Stirrups The minimum peripheral length of a soft eye should be four times the rope lay length. This is so as to ensure that the lay of the rope is not disturbed. It is extremely difficult to fit thimbles whenmaking Flemish eyes. If the sling is to be used in a choked situation then a protective attachment, known as a stirrup thimble, is commonly used to protect the rope from damage Hand Spliced Eyes A hand-spliced eye is an eye formed at the end of a sling by the traditional method of threading the individual strands of the rope back along the main body of the rope in a prescribed pattern Whilst this type of eye is now less popular than the more modern ferrule secured eye, it is still available and preferred by some users In the case of hand splices, these should be made with five tucks against the lay of the rope. The type of splice where the tucks are made with the lay of rope, should not be used as this tendsto undo if the rope rotates in use and is effectively banned from splicing wire ropes for lifting purposes Wire Rope Grips For many years it has been common practice to make temporary eyes in wire rope, particularly winch wires, by using clamp-type grips, commonly known as ‘bulldog’ grips. The use of such gripping devices which clamp the wire to form temporary eyes is not recommended for the manufacture of slings. The reason for this is that tests have showed that these grips do not give an acceptable or consistent level of safety. Sockets and Fork Ends Sometimes used fitted to the rope by a compression process or 65 by a white-metal or resin bonding process. The manufacturer’s/supplier’s advice should always be sought and Page followed where their use is intended. © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Course Workbook Single and 2-Part This is not a common way of producing sling legs but is used for WireRope Slings very large capacity slings, so the examiner needs to be aware of them. An endless sling is produced and then a thimble is bound at each end. The thimbles that are used must be two or three sizes larger than would normally be used for the rope diameter. The looped sling leg will take a greater load than a single part sling made from the same size rope and a thimble for the actual rope diameter would collapse under the increased load it has to take. In order to make the thimble fit the rope it is necessary to serve the rope with wire or spun yarn. A sling leg produced by this method is not capable of twice the WLL of a single part of the rope, as one might expect, but is in the order of 25% less than this. This is due to the increased stress due to the rope being bent around such a tight radius. Notes: 66 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Course Workbook Rating of Wire Rope Slings The working load limit of a wire rope sling depends upon the following factors: The size and tensile It will be noted that different but similar constructions of rope of strength of the rope equal tensile strength have the same minimum breaking loads. The core of the rope A rope with a steel core will have a marginally higher breaking load than a similar rope with a fibre core. It will at the same time be slightly less flexible and more resistant to crushing. The number of parts of wire For some applications, double part legs are preferable as they rope (single or double) per give more flexibility than the equivalent capacity single part leg. sling leg They are however more costly and therefore normally only used for large capacities in order to utilize smaller diameter wire rope whilst offering a greater bearing area to the load. The geometry of the sling For example, the number of legs and, in the case of multi-leg slings, the angles between the legs and the vertical and their arrangement in plan. The method of rating This may be either the uniform load method or the trigonometric method, dependent on the application. Whilst slings may be found in service rated by either method, the uniform load method is the preferred method for rating multipurpose slings. The maximum angle of inclination at which the sling may be rated is 60° (120° included angle) but it may only be rated for use at 45° (90° included angle). The SWL to be marked on the sling should be assessed by a Competent Person and will be the same as the WLL in normal conditions or less than the WLL under special conditions. The maximum load that can be lifted by a sling may also vary from the marked SWL depending upon the method of use. Notes: 67 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Course Workbook Chain Slings How is a Chain made? Chain is made by passing lengths of steel bar into a machine that uses a series of automated processes to shape, form and weld each link into the finished chain. Following welding of the links, the chain will undergo a process of heat treatment to achieve the desired material properties such as strength, ductility and toughness. Chain slings are versatile and provide a safe method of lifting loads, but it is important that they are used correctly to avoid damage and potentially serious incidents. Material Chain slings manufactured from wrought iron are obsolete and no longer available. Similarly, mild steel chain slings have been obsolete since the early 1980’s following the publication of newer standards which specifically exclude the use of this grade of chain for lifting applications. However, it is possible that examples of wrought iron and mild steel chain slings may occasionally be found in service, but their continued use is not recommended by LEEA. Most modern chain sings are constructed from grade 8, and although not yet covered by standards in certain regions, grade 10 chain is becoming increasingly popular. Medium tolerance chain intended for sling manufacture needs to be more ductile to withstand shock loading. However, in use it is not subject to wear and can therefore have a softer skin. As it does not mate with other moving parts, it does not need to have such a precise pitch. Calibration When chain is produced by machine the links are not all exactly the same exact shape; the sides have a slight curve. When the manufacturer ‘calibrates’ it by the application of a force, the links bed down on each other and the sides of the link straighten. As a result, the chain extends by a very small amount. With load chains for lifting appliances (e.g. hand chain hoist), it is vital that the links are of precise size and form so that they engage correctly in the pocketed load wheels of the machine. This is achieved by manufacturing the chain to a calculated undersize. The finished chain is then subjected to an increased force, which pulls it to the required even shape, size and pitch. 68 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Course Workbook Finish Various finishing treatments are then given to fine tolerance chain to increase its wear resistance (e.g. case hardening). The loss of some ductility due to the manufacturing and finishing processes is relatively unimportant for load chains. However, these features are undesirable in a sling chain where it is less likely to wear. Sling chain is more liable to be shock loaded, so good ductility is essential. Fine tolerance chain may be recognised in two ways. The calibrating process has the effect of removing all of the residual scale from the heat treatment process and many of the finish treatments include corrosion resistant finishes. As a result, it has a bright finish and of course there is also the grade mark. Assembly Older chain slings, and currently a few for special applications, were assembled by a blacksmith and had welded joining links. These are very rarely found in service nowadays. Modern chain slings are assembled from components that have mechanical fixings, such as spiral roll pins, to retain them. They are therefore assembled and repaired very easily using standardised ranges of fittings. A full range of fittings is available with the clevis form of chain connection, such as hooks, shackles and egg links This system of assembly minimises the number of components necessary to assemble a sling, as the terminal fittings locate directly onto the chain With clevis attachment, the end link of the chain is passed into the jaw of the clevis A load pin is passed through the clevis and chain, on which the chain seats Spiral roll pins or circlip type fixings are used to lock the load pin in position ▪ A full range of fittings is available with the clevis form of chain connection, such as hooks, shackles and egg links ▪ This system of assembly minimises the number of components necessary to assemble asling, as the terminal fittings locate directly onto the chain ▪ With clevis attachment, the end link of the chain is passed into the jaw of the clevis ▪ A load pin is passed through the clevis and chain, on which the chain seats ▪ Spiral roll pins or circlip type fixings are used to lock the load pin in position 69 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Course Workbook ▪ For the connection of the chain to master links a simple shackle like ‘coupler’ is available in some systems: Rating of Chain Slings The factors to be considered fall into three main groups 1. How the sling is attached to the load 2. The geometry of the sling, i.e. the angle of the legs to the vertical and the arrangement of the legs in plan 3. The number of legs in use The amount of load that will be carried by an individual leg will depend on the angle between each of the legs and the vertical, the arrangement of the legs in plain view and the total load being lifted. The reduced ratings for slings when used in choke hitch take account of higher stresses at the point where the choking hook or link bears upon the chain. The maximum angle of inclination at which the sling may be rated is 60° (120° included angle) but it may only be rated for use at 45° (90° included angle). The SWL to be marked on the sling should be assessed by a Competent Person and will be the same as the WLL in normal conditions or less than the WLL under special conditions. The maximum load that can be lifted by a sling may also vary from the marked SWL depending upon the method of use. Notes: 70 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Course Workbook Textile Slings Textile slings are manufactured from man-made fibres such as: Polyamide (nylon) Polyester Polypropylene Additionally, fibre rope slings may also be produced from natural fibres such as: Manila Sisal Hemp Although these will very rarely be found in service nowadays. New, specialist man-made fibres, such as HMPE (High Modulus Polyethylene) are now being produced to manufacture specialised lifting slings. These feature high cut and abrasion resistance; Although the various fibres have many common features, they react differently to temperature, chemical contact and environment. We will consider these matters in the Lifting Accessories Diploma training course. Types of textile slings Textiles slings can be found in various forms: 71 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Course Workbook Flat woven webbing slings Are also commonly known as belt slings, are used for a variety of lifting purposes. They are a textile sling which is soft and easy to handle whilst offering rigidity across their width. They are ideal for handling loads which require some support when being lifted as the load is spread across the full width of the webbing, avoiding point contact as is the case with chains or ropes. They are therefore less likely to cause damage to the load’s surface than rope, wire rope or chain slings. However, they are less robust and more easily damaged than equivalent capacity wire rope and chain slings. Roundsling Roundslings comprise of a core enclosed in a protective cover. The core is the load-bearing part of the roundsling and is in the form of a hank of yarn made up from one or more strands of the parent fibre material wound together continuously and joined to form an endless sling. The protective cover is a woven tubular outer sleeve of the same parent material as the core, whichis designed to be non-load bearing as it is intended only for protection and containment of thecore. Man-made fibre roundslings are an endless textile sling that is soft and pliable to use, easy to handle and especially useful on delicate surfaces. They are less robust and more liable to damage than equivalent capacity wire rope and chain slings. Fire Rope Slings Fibre rope slings are the traditional form of textile sling whose origins are recorded in the earliest history of lifting equipment. Their use has declined in recent years in favour of the newer forms of textile slings, i.e., flat woven webbing slings and roundslings but they may still be found in general use throughout the industry. Fibre rope slings are produced from cut lengths of rope which are then hand spliced. 72 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Course Workbook Fibre rope slings are less pliable than other forms of textile sling and are bulky to handle. Unlike flat woven webbing slings and roundslings they present a hard, point contact to the load although this is less severe than with chain or wire rope. Single leg, multi-leg or endless fibre rope slings can be produced. They are made by hand splicing eyes at each end of a piece of rope or by splicing one cut end of a rope to the other end, forming an endless loop. With multi-leg slings, the eye one end of each sling leg is made through a master link. Where this is done, the use of thimbles is advised to protect the eyes. Eyes are produced by bending the rope to form a loop. The strands at the end of the rope are separated and then tucked back into the standing part of the rope against the lay to form the eye, in a similar way as with wire rope. This is done in such a way that they lock and do not slip when a load is applied. There are differences in the splicing requirements, depending on the type of rope used. This is due to differing coefficients of friction. Identification visually, the various fibres appear much the same. This makes identification extremely difficult. An international system of colour-coded labels, which carry the information necessary to be marked on a sling (see marking), has therefore been adopted in standards as follows: 73 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Course Workbook Shackles Shackles are probably the most common and universal lifting accessory. Their uses are extensive. They may be used to connect a load directly to a lifting appliance, to connect slings to the load and/or lifting appliance, as the suspension for lifting appliances or as the head fittingin certain types of pulley blocks. There are three main types of shackles used for lifting today: 1. Bow 2. Dee 3. Grab types Shackles are normally forged from various grades of steel. Higher quality alloy steels give a higher safe working load than those made in higher tensile steels, while higher tensile steel shackles have a higher safe working load than those made in mild steel. Some manufacturers continue to make shackles to old now withdrawn standards, whereas many have now adopted the current standards. The older, now withdrawn shackle standards fully specified all dimensions of the shackle. In contrast, the current standards tend to specify only some dimensions fully, the rest being specified as a maximum or minimum value. Shackles to the older standards are sized by the diameter of the material in the shackle body and not the diameter of the pin. Shackles to later standards are usually sized by their WLL. Dee Shackle All shackle standards specify dee shackles, with some specifying both a large dee and a small dee shackle. A large dee shackle is a shackle that has ample internal clearances in the body and jaw, and which is appropriate for general engineering purposes. A small dee shackle is a shackle that has moderate internal clearances in the body and jaw but, size for size has a SWL higher than that of the large dee. It is suitable for use with hook eyes, eyebolts, egg links, wire rope thimbles, etc. and for the head fittings of ships’ blocks. Bow Shackle Similarly, all shackle standards specify bow shackles, with some specifying both a large bow and a small bow shackle. A large bow shackle is a shackle which has ample internal clearances in the body and jaw, and which is appropriate for general engineering purposes. A small bow shackle is a shackle which has moderate internal clearances in the body and jaw but, size for size, has a SWL higher than that of the large bow. It is suitable for use with the eyes and bodies of hooks, eyebolts, egg links, wire rope thimbles, etc. and for the head fittings of ships’ blocks. Grab Shackle A grab shackle is a dee shackle having a screwed countersunk pin, designed for use with grabs where the shackle must pass through a circular aperture of minimum diameter. 74 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Course Workbook Application The selection of the shape of the shackle body will depend on the intended use. It is desirable to use a shackle with as small a jaw opening as is consistent with an adequate articulation of the connection. Dee shackles are, in general, used to join two pieces of lifting equipment. Bow shackles are, in general, used where more than one attachment is to be made to the body or to allow freedom of movement in the plane of the bow. Pins There are two types of shackle pin in common use, the screw pin, and the bolt, nut and cotter pin (commonly referred to as the safety pin or 4-piece shackle). Screwed pins with eye and collar are the most common type of pin and are suitable for a wide range of uses. However, if they are subject to movement and vibration (e.g. by a sling moving over the pin), they can loosen and unscrew. The bolt with hexagon head, hexagon nut and split cotter pin is used where a positive connection is required as it cannot unscrew unintentionally. They are also ideal where a permanent connection is required, (e.g. connecting the top slings to a spreader beam). Notes: 75 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Course Workbook Eyebolts We will consider the main three types of eyebolt: 1. Eyebolt with link 2. Collared 3. Dynamo Eyebolt with Link This eyebolt has advantages over the other patterns of eyebolt when the loading needs to be applied at an angle to the axis and/or the plane of the eyes. Provided that the angle of the load to the axis of the screw thread does not exceed 15° they may be loaded in any direction to the full SWL rating. Thread sizes range from 20mm to 48mm in the metric coarse pitch series or ¾” to 1¾” in the imperial BSW or UNC threads. They have a small, squat, eye that is blended into the collar in all directions and a link is fitted to allow articulation and connection with other lifting components. The link is designed to accept a hook of the same capacity. Compared to size for size with Collar Eyebolts, the SWL for axial load is lower. In all other arrangements, the SWLs are relatively greater than those of Collar Eyebolts when used in the same conditions. Unlike the Collar Eyebolt, the load can be applied away from the plane of the eye, as the link will articulate to align and the collar has equal strength in all directions, making correct fitting easier. 76 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Step Notes NOTES FROM THE VIDEO: Collared Eyebolt Designed for both axial and angular loading. The eye is blended to the collar in one plane. However, the eye is not large enough for direct connection to a hook and it is necessary to use a shackle for connection to other components. They are generally available in a range of capacities of 0.4t to 25t SWL with corresponding thread sizes of 12mm to 72mm in the metric coarse pitch series, and capacities of 0.25t to 30t with corresponding thread sizes of 3/8” to 3” BSW or UNC. The SWL range of the imperial threaded collar eyebolt differs from that of the metric threaded collar eyebolt because they are intended as replacements for eyebolts to older now withdrawn standards. When used in pairs of the same capacity, the plane of the eye of each eyebolt must not be inclined to the plane containing the axis of the two eyebolts by more than 5°. In order not to overstress the shank, this alignment may be achieved by use of shims up to a maximum of half of one thread in thickness. A reduction in the maximum load that may be lifted is necessary due to the angular loading. This is far more drastic than is required with the Eyebolt with Link. Although in axial loading, size for size, Collar Eyebolts have a higher SWL, their capacity when subject to angular loads is far lower. 77 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Step Notes NOTES FROM THE VIDEO: Dynamo Eyebolt The Dynamo Eyebolt is the most basic in design and the most limited in use because it only suitable for axial (directly vertical) lifting only. Essentially it is a ring sitting on top of the shank and has only a small collar. Although it is limited to axial loads, the eye is large enough to accept a hook of the same capacity. Dynamo Eyebolts get their name from their historical use by electric motor manufacturers, who would fit them to the tapped hole over the balanced lifting point of the motor. They are generally available in capacities of 0.32t to 10t with corresponding thread sizes of 12mm to 52mm in the metric coarse pitch series. Imperial threaded dynamo eyebolts are also available in a range of capacities of 0.25t to 10t with corresponding thread sizes of 3/8” to 2” BSW or UNC. 78 Page © LEEA Academy - FOU (Global) Workbook v 1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Rigging Screw These have a tubular body, internally threaded at each end, with one right hand and one left- hand thread connecting to terminal fittings of various forms, e.g., screwed eyes, hooks or forks. They are also known in some industries as bottle screws Turnbuckle This has an open body consisting of reins, with internally threaded bosses at each end, with one right and one left-hand thread connecting to terminal fittings of various forms, e.g., screwed eyes, hooks or forks. A drilled inspection hole across each end of the body of a rigging screw facilitates checking that the threaded portion of the terminal fitting has adequately engaged with the body. 79 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Notes: 80 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Hand Operated Chain Hoists Hand Operated Chain Hoists Manual chain hoists are very popular and are found in wide use throughout the world. This is because they can be used very effectively in the following applications where: ▪ A permanent installation for infrequent use is required ▪ A temporary installation for erection or maintenance purposes is required ▪ Precise location of the load is required ▪ A suitable power supply is not available The advances in material and manufacturing technologies have enabled much, smaller, lighter and more efficient chain hoists to be produced. Chain hoists use a pocketed wheel into which the load chain must fit, but freely enter and leave. The drive to the pocketed wheel is via a hand chain and screw brake mechanism. The free end of the load chain shall be fitted with a chain end stop to prevent it from passing through completely. All modern hand-operated hoists are fitted with an automatic brake which, when functioning correctly, is capable of arresting and sustaining the load at any position. Students will visit this subject in further detail in the LEEA Manual Lifting Machines Diploma. 81 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Combined types are usually combined with a purpose-made travelling trolley, although a direct connection to the supporting structure may also be possible. The connection between the hoist and the trolley or structure is usually rigid. Lower Capacity Hoists The lower capacity hoists (e.g. 500kg, 1t) lift the load on a single fall of load chain. Higher Capacity Hoists Higher capacity hoists may either be of similar design but with a larger frame or may utilise two or more falls of load chain. The very high capacity hoists may utilise a combination of a larger frame and multiple falls of load chain and may even have two or more frames linked by a yoke. Notes: 82 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Hand Operated Lever Hoists Hand-operated lever hoists are widely used since they can perform both lifting and pulling applications. The ability of the lever hoist to operate in any attitude makes the lever hoist a versatile tool, particularly for rigging. It can be used as an adjustable sling leg to enable a load to be balanced or for line adjustment when positioning - to give just two examples. Two basic types are available: one using fine tolerance (calibrated) short link steel chain, the other using roller chain. Advances in material and manufacturing technologies have enabled much, smaller, lighter and more efficient lever hoists to be produced. Lever hoists use a pocketed wheel into which the load chain must fit, but freely enter and leave. The drive to the pocketed wheel is via a hand chain and screw brake mechanism. The lever hoist will also have a change-over lever with a neutral position which allows the user to set the chain to the correct length (free-wheel facility). The free end of the load chain shall be fitted with a chain end stop to prevent it from passing through completely. Notes: 83 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Lifting and Pulling Machines - using a gripping action on the wire rope Commonly referred to as ‘jaw’ or ‘creeper’ winches in different regions, these winches are widely used throughout the industry for both permanent applications and temporary or rigging applications. They are used as pulling machines as well as lifting, which may permit a lower factor of safety and giving a higher working load limit when the winch is used for pulling. 84 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook All jaw winches operate by the same general principle. Effort to the rope in a jaw winch is provided by two levers, which act via a lever and cam system on keys. Each set of jaws is made up of a top and bottom jaw which are brought together (clamped), or separated (unclamped), by half-moon-shaped keys actuated by levers known as jaw links. The wire rope supplied for use with a jaw winch should be considered as integral a part of the mechanism as a load chain of a chain hoist. Some ropes, which appear to be of the correct size, and which are accepted by the winch, may not be suitable. The efficiency and safety of the friction grip of the winch’s jaws depend entirely on the rope being the right diameter and constructed to withstand the crushing force of the jaws. With a rope diameter that is too small, the jaws will not grip the rope sufficiently. With a rope diameter that is too large, the rope may become stuck in the winch, putting the winch out of operation. It is therefore essential that only ropes approved by the manufacturer are used with the specified jaw winch. One end of the load rope is plain tapered and fused to allow entry into the machine. The other end has a terminal fitting for attachment to the load. 85 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Hydraulic Jacks Hydraulic jack bodies are commonly manufactured from aluminium, steel or cast iron. The material used affects the design, size, self-weight and capacity of the jack. Hydraulic jacks use oil and the body of the jack acts as a reservoir for the oil. When the jack is operated, the oil is passed through a system of non-return valves to the underneath of the lifting ram. When more oil is delivered through each stroke of the handle, the lifting ram is forced out of the chamber lifting the load. The load is lowered by opening a valve which allows the oil to return to the reservoir by the load pushing down onto the lifting ram. 86 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Mechanical Jacks There are several types of mechanical jack available. The ‘ratchet’, ‘screw’ and ‘journal’ jack most commonly found in service: 87 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Ratchet jacks The body of the jack contains a pair of pawls that engage in a rack. Operation of the jack causes the pawls to raise or lower the rack, which is fitted with a lifting head and toe, providing alternative positions for supporting the load. The full rated load may be supported on the head or toe. During the jacking operation, the operative effectively carries the load via the operating lever. At the end of each stroke, the load is sustained by a pawl. Screw jacks Consist of a single hollow casting with a square form female thread into which fits a male screwed shank. A swivel head is fitted to the shank to support the load. Directly turning the screwed shank causes it to raise or lower. Journal jacks Consists of a cast body that houses a bevel gear and screw mechanism. The operation of a ratchet lever turns the gears that drive a screwed shank. This in turn drives a running nut that is captive in the lifting journal and therefore causes the journal to raise or lower. Notes: 88 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Crane Forks and ‘C’ Hooks Crane forks and C-hooks are suspended from crane hooks but lift loads directly without the need for other lifting accessories. Whilst C-hooks are usually designed to lift a specific load, crane forks are of a more general nature and are usually supplied as a standard product. Although very different in design, crane forks and C-hooks have much in common, which enables them to be considered together. Differences will be noted where relevant. ▪ Crank forks: These are used to lift palletised or similar loads suspended from a crane hook. ▪ C – Hooks: These are used to lift hollow loads such as pipes, paper rolls or coils of steel. Fabricated from a profiled plate or rolled beam sections. 89 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Powered Lifting Machines (Appliances) Powered lifting machines are widely used in industry, often as part of a larger lifting installation, e.g. with an overhead runway, jib crane or overhead travelling crane, or where a permanent lifting facility is required. They may also be used for fixed position lifting applications or where a temporary powered lifting facility is required. Powered lifting machines are available with electric or pneumatic operation, but the most common in general use at the present time are electrically operated. Powered lifting machines are ideal for heavier or repetitive lifting applications as they offer the following advantages over manually operated chain hoists: ▪ Speed of operation ▪ Less fatigue for operatives, particularly on long lifts ▪ Operatives may be remote/away from the load Notes: 90 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Electric Chain and Wire Rope Hoists Modern electric power-operated hoists are normally fitted with low voltage control which is derived internally within the unit by a transformer. This is usually in the range of 24 to 50 volts AC or DC and is often known as ‘Extra Low Voltage’. Older hoists and special purpose hoists may not have LV control. It should also be noted that it is common in many European countries to use mains voltage control. The two principal lifting media used with all power-operated hoists are: Short link round steel chain Steel wire rope HMPE and textile belt materials In hoists that use chain, the chain passes over a pocketed wheel with the slack side of the chain hanging loose. A collecting box may be used to house the slack chain, but as this sits below the body of the hoist it restricts the height that certain loads may be lifted. In hoists that use wire rope, the wire rope passes on and off a drum upon which it is stored. The range of lift is limited by the amount of wire rope that the drum can accommodate. Pneumatic Hoists Pneumatic power-operated hoists tend to be more limited in use than electric power- operated hoists, mainly due to the problems associated with the provision of a suitable air supply. However, they offer many advantages over electrically operated equipment and as a result are widely used in industries where the air is provided for other purposes or where the safety aspects associated with air- operated equipment are a major consideration. 91 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Hydraulic Hoists The hydraulic hoist provides smooth and accurate lifting and lowering operations and is very quiet in operation. An electric motor is used to run a hydraulic motor. The hydraulic motor is a mechanical actuator that converts hydraulic pressure and flows into torque, or rotation, which in turn moves the hoist. The advantages of this form of the machine are that the electric motor does not have to be physically near the fluid drive, so the system is virtually noiseless. They are regularly used in intrinsically safe areas, as is the pneumatic hoist. Electrical Controls Other control options, such as radio or infra- red controls, enable remote or central control. They are useful in areas where direct access may not be possible. Multi-point controls, usually wall-mounted, enable hoists to be controlled from several positions, which is useful in applications such as raising loads through several floor levels. Such arrangements must be suitably interlocked to prevent more than one control from operating at a time. A further essential requirement with this arrangement is the provision of emergency stop buttons to override all control positions until manually reset. Various examples of Electrical Controls 92 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Supporting Structures for Hoists and Light Crane Systems Built-in Runways These are usually runway beams supported by existing building structures. The ‘simply supported’ and ‘encastred’ type runways are most common. Suspended Runways These runways can also be suspended from suitable roof members or beams built into the building structure. 93 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Free Standing Runways Where no existing suitable supports are available, then free-standing runway structures are common. Special track systems (Light Crane Profiles) Special track sections are quite versatile and are often supplied in kits, sometimes referred to as light crane systems, which can be assembled in various configurations, such as simple runways, runways with switches, turntables, etc, and even low capacity bridge cranes. 94 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Switches and Turntables The use of runway switches and turntables allow the lifting appliance to be transferred from one runway system to another. Notes: 95 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Crane Systems Slewing Jib Cranes Slewing jib cranes are widely used in industry in conjunction with manual or power operated lifting appliances where a permanent facility is required to perform both lifting and limited moving operations. Typical examples of their use being over workbenches, in fitting and maintenance shops, over machine tools and in loading and unloading bays. They offer a wide area of floor coverage within the slewing radius of the jib arm and are ideal where full overhead travelling crane coverage may be either impracticable or uneconomic. They are often used to supplement overhead travelling cranes. Slewing jib cranes are often designed, supplied and tested without lifting appliances and it must be realised that a slewing jib arm becomes an effective crane only when fitted with a hoist, hoist and trolley or similar lifting appliance. Wall or Column Mounted: The jib arm, king post and bracing are assembled as a single unit. They may be either over - braced or underbraced in design dependent on the intended use and the location of the installation. Top and bottom bearing brackets fit onto the king post and these, in turn, are fixed to the supporting structure. Free Standing: The jib arm and supporting column are assembled as a single unit which includes all mountings and bracing. They may be either over-braced or underbraced in design dependent on the intended use and the location of the installation. The supporting column is usually manufactured from a square box section, fabricated sections or tube dependent on the required angle of slew. The angle of slew and intended use will also affect the design of the king post and mounting structure. Free standing jibs are available with a wide variety of slewing angles. They may have a full 360° angle of slew, allowing for continuous rotation if a tubular column is used, or be limited to 270° angle of slew if a square box or similar section column is used. 96 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Mobile Gantries: a mobile gantry is normally used in areas where it is not cost-effective to have a permanent installation. A mobile gantry is a free-standing structure comprising a runway beam and two supports or A-frames assembled in a goalpost-like configuration. The supports are usually mounted on wheels or castors to enable the structure to be relocated by man-power only; they may however be mounted on free-standing feet requiring the structure to be dismantled for transportation. Goalpost Gantry: This consists of a runway beam, often in the form of a manufacturer’s branded track section, with single column supports. Lateral stability is provided by a base member on which the column is mounted. This design is limited to light loads, usually up to 500kg, and light - duty applications. ‘A’ Frame Gantry: this is the most common type of mobile gantry. It consists of a runway beam, usually of standard rolled steel section, with supports in the form of an ‘A’. Lateral stability is given to the structure by the shape of the supports. This design is available in all capacities, usually up to 5 tonnes. 97 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Adjustable Height Gantry To provide limited variations to the erected height of the runway, an adjustable height gantry has telescopic supports enabling the runway to be raised or lowered to suit differing site conditions. This facility is not intended for use under load but is to allow for varying lifting height requirements only. This design is available in all capacities, usually up to 5 tonnes. Foldaway Gantry Designed for easy dismantling and storage. They are intended for applications where regular dismantling and transportation is necessary or where the usage is such that long periods of storage occur. This design is usually limited to loads of up to 2 tonnes. 98 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Self-Erecting Gantry Designed with the provision of hand winching mechanisms that allow the structure to be assembled horizontally on the floor. Operation of the winches pulls the side members of the ‘A-frame supports together until the gantry is in its operating position. Additional locking structural components are then inserted making the structure rigid. This design is usually available in higher capacities from 2 tonnes upward. Crane Supporting Structures Tracks Tracks will generally be constructed as ‘top (Gantries) running’ or ‘under-slung’. Top running gantries are supported in various ways. Crane Tracks: Generally manufactured from standard constructional sections. For top running cranes a rail section is usually welded to the top flange of the track beam. For underslung cranes, the crane will run on the bottom flanges of the beam. Dependant on the crane type the track will either be suspending from a cross beam known as a carrier beam or fitted directly to the tops of the supporting columns. Crane or Track Rails: Depending on the duty, the rail will have a profile similar to one of those shown below, but more often than not for light duties, this will be a square bar. These rails are normally fixed by intermittent welding and if not welded with the rail securely clamped to the beam weld, cracking will occur in service. Bridge and Gantry Cranes: Bridge and gantry cranes provide a means of lifting and transporting loads over the area covered by the crane. Some bridge and gantry cranes may use manual effort to lift, lower and move the load. However, it is more usual for some, or more typically all, of the crane’s motions to be electrically powered. There are four main types: ▪ Top running bridge crane ▪ Under-slung bridge crane ▪ Semi-portal gantry crane 99 ▪ Portal gantry crane Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Top Running Bridge Crane Distinguished by running on the top of rails which are part of the crane supporting structure. Under-Slung Bridge Crane Distinguished by running on the bottom flanges of the cranes tracks. Because of the under-slung arrangement, the bridge of this type of crane can have a cantilever at one or both ends. Two or more such cranes running on parallel sets of tracks can be fitted with latching mechanisms to facilitate the transfer of loads from one crane to another. Portal Bridge Crane: Distinguished by running on a low-level track, usually at ground level, with the bridge girder or girders supported on legs. The bridge of this type of crane can have a cantilever at one or both ends. Semi-Portal Bridge Crane: A combination of a top running bridge crane and a portal bridge crane. The bridge of this type of crane can have a cantilever at the end of the span supported by the legs. 100 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Light Crane Systems (Parallel Track, Bridge and Hoist) Defined as an assembly of lifting devices, bridges, trolleys and tracks with their suspensions for lifting operations and usually manufactured from proprietary sections of steel. There are many different manufacturers of these systems and modular in design. There are several advantages to be gained in using a light crane system: ▪ Smooth travelling movements ▪ Silent running of the trolleys ▪ Less wear and less pollution (nylon wheels) ▪ Modular system ▪ Pendulum construction (less stress on the support structure) ▪ Easy installation ▪ Easy ,modifications if required at a later date ▪ Reduced maintenance The general configuration would be two parallel tracks suspended from the ceiling or building structure with a single or dual-bridge bridge crane running between the tracks. The single bridge version would normally be of manual push/pull type long travel fitted with a manual or electric chain hoist suspended from a trolley running inside the bridge profile section, and the dual - bridge would be fitted with a trolley that is suspended between the two bridge sections. This would normally accommodate an electric chain hoist. Installations may be altered and extended with relative ease to meet changing needs of the end user. Power to the hoist and travel/traverse motions can be supplied by festoon cables suspended from trolleys that run inside the track profile, or it can be fed through internal conductor bars mounted inside the top of the track profile. The motor assembly has a collector arm inside the track which picks up the power supply. 101 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook The conditions that offshore containers are transported and handled in mean that the rate of wear and tear is high. An offshore container built to a recognised standard is designed, manufactured and tested to be able to withstand this wear and tear. An offshore container is also designed with pad eyes to enable a suitably designed lifting set to be the recognised method of lifting offshore. There are various types of offshore container in service, including waste skips, baskets and skids for machinery/plant assemblies. Specific marking requirements are prescribed by the standard that the container is designed to conform to. 102 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook There are enhancement factors that must be considered when designing these lifting sets, due to the dynamic motions that an offshore container will experience when being lifted offshore. There must also be a top leg (forerunner) fitted if the lifting set does not hang over the long side of a container to a specific height. This will ensure the rigger does not have to put themselves in danger by standing on top of a container. Notes: 103 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Mobile Cranes Mobile Cranes can be manufactured in many forms. The most common types of mobile crane are: Yard crane Used in factories and plants where small loads can be carried on the crane’s platform. Truck-mounted crane Has a multi-use crane with fast relocation from job to job. Rough terrain crane Ideal for use on construction sites on uneven ground. Easily able to relocate over rough ground and can pick up a load and carry it whilst moving. City crane Designed to work in often confined spaces of urban areas. 104 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook All terrain crane A very common and popular type of crane. It is designed to travel over different types of terrain and is also able to relocate at speed on highways between sites. Loader crane A truck loader crane, truck-mounted crane, HIAB or ‘crane truck’ is a crane that is mounted to a truck, either just behind the cab or just behind the deck. It is designed to lift goods on and off the truck and means that a driver can deliver goods exactly where is required without the need for a forklift, telehandler or separate crane. 105 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Tower Cranes Tower Crane Tower cranes are extremely common at major construction sites. Often rising hundreds of feet into the air with a sizeable radius (outreach). The construction crews use tower cranes to lift steel, concrete, waste skips, generators and a wide variety of other building materials. Notes: 106 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Offshore Pedestal Crane Defined as a pedestal-mounted, elevating and rotating lifting device used to transfer materials and personnel to or from marine vessels, barges, and structures, a standard used to design and manufacture offshore cranes. 107 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Knowledge Check The questions covered below do not form part of any formal qualification scoring. The intention is to just check and help embed the content we have covered so far. There are 5 questions which are all multiple choice. Question 1: What does ACoP stand for? (Select one answer) □ Approved Certified Operating Procedures □ Accreditation of Certified Operating Procedures □ Applied Codes of Practice □ Approved Codes of Practice Question 2: From the list below, select which ones would fall into the category of Lifting Accessory. (Select all that apply) □ Chain sling □ Crane □ Hoist □ Eyebolt 108 □ Jack □ Shackles Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Workbook Question 3: From the list below, please select all that would fit into the criteria of 'Types of Verification'. (Select all that apply) □ Hardness test □ Electromagnetic wire rope examination □ Pre and Post Inspection □ Proof load test □ Shear test Question 4: Velocity Ratio = Distance moved by effort ÷ Distance moved by load (or DME ÷ DML) □ True □ False Question 5: Who is responsible for the disposal of lifting equipment? (Select one answer) □ A. Employer □ B. Owner / End user □ C. Competent Person 109 Page © LEEA Academy – FOU (Global) Workbook v1.6 Jan 2024  LEEA – Foundation Certificate (Global) – Step Notes Lifting Equipment Engineers Association Lifting Standards Worldwide www.leeaint.com © LEEA Academy – FOU – Workbook April 2022 – v.1