Mobile Cranes Diploma (MOB) Quiz

Mobile Cranes Diploma (MOB)

• The LEEA Mobile Cranes Diploma is a globally recognized qualification for lifting equipment testers, inspectors, examiners, repairers, and maintainers.
• The diploma is essential for anyone engaged in the testing, inspection, and examination of mobile cranes.

Learning Outcomes

• Upon completion, students will be able to perform thorough examinations of mobile cranes in service and assess their fitness for further use.
• Students will be able to refer to and extrapolate information from sources to support their analysis of lifting equipment suitability.

Scope of the MOB Course

• Working on-site
• The examiner's tools and equipment
• Types of mobile cranes
• Types of examination
• Assessment criteria
• Preparation for thorough examination
• Competency
• Rated capacity indicators and rated capacity limiters (RCIs and RCLs)
• Load testing of mobile cranes
• Thorough examination – mobile crane carrier/chassis
• Thorough examination – mobile telescoping crane structure
• Chain and wire rope examination
• Rated capacity charts
• Load indicators

Working On-Site

• Expectations of high professional standards in the lifting equipment industry
• Prioritizing risk mitigation and safety
• Importance of competence, technical abilities, and managing standards of service

The Examiner's Tools and Equipment

• Hand tools required for mobile crane examinations
• Measuring equipment, including spirit level, tyre pressure gauge, and inclinometer
• Calibration of measuring equipment according to relevant standards
• Use of lighting and cleaning materials to facilitate examinations

Types of Mobile Cranes

• Rough terrain cranes
• Truck mounted cranes
• All-terrain cranes
• City cranes
• Yard cranes
• Crawler mounted telescopic cranes

Types of Examination

• Pre-use inspection
• Interim inspection
• Thorough examination

Pre-Use Inspection

• Visual checks for signs of defect, damage, or failure
• Functionality checks of the crane
• Carried out by the operator prior to use
• Competence involves training and assessment

Interim Inspection

• Determined by risk assessment
• Focus on critical components
• Frequency and extent of inspection determined by risk assessment and manufacturer's literature

Thorough Examination

• Performed at specified intervals

• Before putting the crane into service for the first time

• Following major refurbishment, repair, or alteration

• Following an exceptional occurrence

• Scope of examination decided by the competent person

• Consideration of risks, likelihood, and consequences of failure

• Account for the age of the crane and likely deterioration

• Manufacturer's records of inspections and tests considered### Scope of Periodic Examination

• The competent person should carry out a thorough examination aligned to the specific scope of examination for the particular crane.

• The defined scope of thorough examination should be drawn up by a competent person in advance and identify the parts of the crane that require examination.

• The scope should include supplementary reports and tests, including witnessing requirements and NDT requirements for the crane structure and mechanisms.

Components to be Included in the Scope

• Manufacturer's information plate/label and duty charts
• Tyres and wheels
• Axle locking systems
• Crawler track
• Crane chassis
• Outrigger jacks and beams
• Chassis braking system
• All bolts, pins, and other fastenings (visual inspection)
• Slew section structure, including fasteners and slew ring
• Slewing mechanism (examination throughout its full range of movement with jib at maximum radius)
• All pipe work and connections (including rigid and flexible hoses) (visual inspection)
• Hydraulic cylinder fittings (visual inspection)
• Oil and fluids (visual inspection)
• Superstructure and jib (visual inspection)
• Fly jib and mounting attachment (visual inspection)
• All pivoting joints on the jib and attachments of the crane (visual inspection)
• Telescoping extensions on the crane (operation and visual inspection)
• Wire running and static ropes, including terminations
• Pulleys/sheaves and drums, including guards
• Cab, including controls, markings, indicators, seating, windows, heating
• Falling object protection structure (FOPS) bars, wipers, and load charts

Assessment Criteria

• Accuracy of limiting and indicating devices – within manufacturer’s tolerance
• Adjustment – as specified by manufacturer
• Alignment – within manufacturer’s tolerance
• Backlash – within manufacturer’s tolerance
• Bearing play – within manufacturer's tolerance
• Brake performance - within manufacturer's tolerance
• Corrosion – affecting strength or functionality
• Cracks – affecting strength or functionality
• Cylinder creep – within manufacturers tolerance
• Damage – affecting strength or functionality
• Distortion – affecting strength or functionality
• Fluid levels – within manufacturer’s tolerance
• Functionality – as intended by manufacturer
• Guards – presence and condition
• Leaks – affecting strength, functionality, and slips
• Lubrication – adequacy
• Markings – presence, accuracy, and condition
• Mode of operation – as intended by manufacturer
• Obstructions impeding safe access
• Rope fit, reeving – as specified by manufacturer
• Rope specification – as specified by manufacturer
• Rope condition
• Security – attachment of components and sub-structures, fasteners, welds
• Seizure – full or partial seizure of rotating components
• Tidiness – general housekeeping
• Wear – affecting strength or functionality

Preparation for a Thorough Examination

• The crane should be positioned in a safe and suitable area for the examination.
• The crane must be clean enough for the examination to be conducted without the potential to conceal any defects.
• Ensure that safe access and egress arrangements are in place.
• I.D. and rated capacity markings should be present and clearly marked.
• The competent person should check for any defects or malfunctions recorded for the crane.

Competency

• Competency of personnel carrying out thorough examinations is critical in ensuring that mobile cranes are examined correctly, methodically, and thoroughly.
• The competent person should have the necessary attributes, competencies, knowledge, and experience to enable them to carry out effective thorough examinations of cranes.
• Continuous Professional Development (CPD) is essential for maintaining currency with developments in the field of work and the quality and relevance of the skill set.

Rated Capacity Indicators and Rated Capacity Limiters (RCIs and RCLs)

• RCIs and RCLs should be included in the thorough examination.
• A thorough visual examination of the individual parts and components should be carried out.
• Where reasonably practicable, a calibration check and functional test of RCIs and RCLs should be carried out.
• Calibration is normally carried out by suspending calibrated weights from the crane to a maximum of 110% of rated capacity.### Load Testing Mobile Cranes
• Before testing, the competent person should seek advice from the manufacturer and conduct a visual examination of the crane and test area.
• A thorough examination of the crane should be carried out, including verification that the crane is rigged in accordance with the manufacturer's instructions.

Functional Test

• A functional test with no load applied should be carried out to determine whether the controls, switches, contactors, and other devices operate correctly.
• The adjustments of the brakes and limit switches should be checked, and tests carried out to determine whether they are operating correctly.

Support Systems during Load Testing

• Outriggers: check that the intermediate extension position is clearly marked, the manufacturer's duty chart indicates the correct rated capacities, and provision is made to accommodate specified intermediate extensions.
• Counterweight: variations in counterweight affect crane stability, and the manufacturer's duty charts specify ratings applicable to each counterweight.
• Jibs: before overload testing, check that the jib is fitted to the crane in accordance with the manufacturer's instructions.

Levelling and Lifting

• The importance of levelling the crane cannot be over-emphasized; the crane should be level to ±0.5% slope.
• Tyre pressures are critical for retaining the necessary stability margin of mobile cranes.

Lifting Capacities

• The load ratings marked on mobile cranes indicate the gross loads, and an allowance should be made for the load imposed by suspended hook blocks, slings, and lifting accessories.

Supplementary Load Testing

• The crane should be functionally tested without a load applied to determine whether it is working properly.
• The efficiency of the crane's hoist brake(s) should be tested with the load that gives the maximum line pull on the hoist rope(s).

Post-Test Examination

• On completion of the overload test, a further thorough examination of the crane should be carried out.

Thorough Examination

• Mobile Crane Carrier/Chassis:
  • Manufacturer's information plate/label and duty charts should be examined.
• Lights:
  • Headlights, sidelights, warning lights, indicators, hazards, windscreen wipers/washers, and registration plate should be checked.
• Hook Attachment Points:
  • Particular attention should be paid to the hook attachment point, especially bolts or welds that are not normally visible.
• Operator Cab:
  • Examinations of housekeeping, control identification, seat and safety belt, condition of operator pedals, and external condition of the cab should be carried out.
• Tyres and Wheels:
  • Tyre condition, size, type, tyre pressures, valve caps, and fixing studs/nuts for correct torque setting should be checked.
• Automatic Carrier Levelling and Suspension System:
  • Raising and lowering of the suspension should be observed, and any issues investigated.
• Hydraulics:
  • Hydraulic tank oil level, filter, and pipes should be checked for leaks and condition.
• Outrigger Jacks and Beams:
  • Outrigger beams should be visually examined to ensure they are level, and all visible hoses, connections, and pipes should be checked for cracks, deformation, or leaks.
• Controls and Level Indicators:
  • Condition of operating controls, level gauges, and labelling should be checked.
• Power Take Off:
  • Drive shaft and Power Take Off Shaft should be visually examined to ensure they are secure and engaged.
• Access Ladders:
  • Access ladders should be checked for damage, missing steps, attachment fixtures, broken welds, and missing bolts.
• Crane Structure:
  • Manufacturer's plate, serial number, model, year of manufacture, counterweight and counterweight attachment system, operator cab, and boom should be checked.

Note: Some points have been condensed for brevity.