Thursday 21 June 2012

Lifting- slinging

Lifting- slinging
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when taking a course as a'designated person for lifting operations I was horrified to reaise just how dngerous some of the operations I had been carrying out. This page demonstrates the lifting factors that you should be applying to lifting accessories

Sling Angles

The abve shows the loading in slings depending on the included angle. It can be seen that fitting too short a pair of slings and thereby creating too great an included angle can substantially increase the loading in the sling and cause it to fail
You should not consider any lifting operation with an included angle greater than 90 degrees and then you should give a 1.5 factor for the slings i.e. the slings should be at least 0.75 tonne each to lift the 1 tonne weight

Choking

This effect also occurs when choking a sling
Should the choke be batterned down it is possible to generate very high included angles severely straining the sling in this area and can easily lead to failure. Should it be necessary to put a wrap on a lift for security then you always consider making 2 full turns. If this is not possible then the included angle should never be reduced below 90 degrees and a 1.5 factor should be applied to the sling.

Inspection Criteria

Eyebolt(Dynamo)

Check Code and SWL legible
Ensure valid test certificate
Check Threads for wear and distortion
Ensure minimum 1.5 threads remaining when pin home
Ensure wear less than 8%
Ensure no nicks, cracks or distortions
Remove corrosion and treat as wear
Ensure no indication of heat damage or weld splatter

Eyebolt(Shoulder)

Check Code and SWL legible
Ensure valid test certificate
Check Threads for wear and distortion
Ensure minimum 1.5 threads remaining when pin home
Ensure wear less than 8%
Ensure no nicks, cracks or distortions
Remove corrosion and treat as wear
Ensure no indication of heat damage or weld splatter

Shackle (Dee)

Check Code and SWL legible
Ensure valid test certificate
Check Threads for wear
Ensure Pin correct for body, of the same material
Ensure pin head shoulder is well seated
Ensure minimum 1.5 threads remaining when pin home
Ensure wear less than 8%
Ensure no nicks, cracks or distortions
Check shackle not opening up
Remove corrosion and treat as wear
Ensure no indication of heat damage or weld splatter

Shackle (Bow)

Check Code and SWL legible
Ensure vald test certificate
Check Threads for wear
Ensure Pin correct for body, of the same material
Ensure pin head shoulder is well seated
Ensure minimum 1.5 threads remaining when pin home
Ensure wear less than 8%
Ensure no nicks, cracks or distortions
Check shackle not opening up
Remove corrosion and treat as wear
Ensure no indication of heat damage or weld splatter

Masterlink

Check Code and SWL legible
Ensure valid test certificate
Ensure wear less than 8%
Ensure no nicks, cracks or distortions
Remove corrosion and treat as wear
Ensure no indication of heat damage or weld splatter

Padeye

Check Code and SWL legible
Ensure valid test certificate
Ensure wear less than 8%
Ensure no nicks, cracks or distortions
Remove corrosion and treat as wear
Remove paint and NDT test weld as required
Ensure no indication of heat damage or weld splatter

Sling(Chain)

Check Code and SWL legible
Ensure valid test certificate
Ensure wear less than 8%
Ensure stretch less than 5%
Ensure Turn or twist a maximum 1/2 turn in 4 metres (hanging)
Ensure no nicks, cracks or distortions
Remove corrosion and treat as wear
Ensure no indication of heat damage or weld splatter
Ensure hooks are of the 'C' design or fitted with safety hook
Ensure hook end is in align with shank
Ensure hook throat opening has not increased by 15%
Ensure hook throat shank wear less than 10%
Ensure Clutch in good condition

Sling(Wire)

Check Code and SWL legible
Ensure valid test certificate
Ensure diameter consistent over length
Ensure no more than 5% randomly broken wires in 10 rope diameters
Ensure no more than 3 wires broken in local group in any one strand or 6 rope diameters
Check external wear less than 10 & of nominal
Remove corrosion and treat as wear
Check for excessive waviness
Check for strand protrusion
Check for core protrusion
Check for localised increase in core diameter due to core deterioration
Check for localised reduction in diameter
Check for memory kinks
Check for flatterned portions
Check integrity of eyes and fittings
Check for heat distortion
Check for pitting and prescence of weld splatter

Sling(Web)

Check Code and SWL legible
Ensure valid certificate of compliance
Check scuffing damage not excessive
Check for chemical/contaminants damage
Check for selvedge damage
Check non load bearing outer sheaf of Round slings not broached
Check for Heat and friction damage
Check integrity of eyes and fittings
Ensure less than 8 lines in 25mm damaged stitching
Check for pitting and prescence of weld splatter

Sling(Multileg)

Check Code and SWL legible
Ensure vald test certificate
Ensure wear less than 8%
Ensure stretch less than 5%
Ensure Turn or twist a maximum 1/2 turn in 4 metres (hanging)
Ensure no nicks, cracks or distortions
Remove corrosion and treat as wear
Ensure no indication of heat damage or weld splatter
Ensure hooks are of the 'C' deisgn or fitted with safety hook
Ensure hook end is in align with shank
Ensure hook throat opening has not increased by 15%
Ensure hook throat shank wear less than 10%
Ensure Legs are of the same length
Ensure Clutch in good condition

Chain Block

Check Code and SWL legible
Ensure valid test certificate
Degrease, disassemble and clean for inspection
Ensure load Chain has wear less than 8%
Ensure load Chain has stretch less than 5%
Ensure load Chain has Turn or twist a maximum 1/2 turn in 4 metres (hanging)
Ensure load Chain has no nicks, cracks or distortions
Remove corrosion and treat as wear
Ensure load Chain has no indication of heat damage or weld splatter
Ensure hooks are of the 'C' design or fitted with safety hook
Ensure hook end is in align with shank
Ensure Gears in good condition
Check chain attachements and Clevis pins
Check bearings, pins rollers for distortion and wear
Check pawl and ratchet for work and operation
Ensure hook throat opening has not increased by 15%
Ensure hook throat shank wear less than 10%

Lever Hoist

Check Code and SWL legible
Ensure valid test certificate
Degrease, disassemble and clean for inspection
Ensure load Chain has wear less than 8%
Ensure load Chain has stretch less than 5%
Ensure load Chain has Turn or twist a maximum 1/2 turn in 4 metres (hanging)
Ensure load Chain has no nicks, cracks or distortions
Remove corrosion and treat as wear
Ensure load Chain has no indication of heat damage or weld splatter
Ensure hooks are of the 'C' design or fitted with safety hook
Ensure hook end is in align with shank
Ensure Gears in good condition
Check chain attachements and Clevis pins
Check bearings, pins rollers for distortion and wear
Check pawl and ratchet for work and operation
Ensure hook throat opening has not increased by 15%
Ensure hook throat shank wear less than 10%

Beam

Check Code and SWL legible
Ensure valid test certificate
Check condition as required

Other

Check Code and SWL legible
Ensure valid test certificate
Check condition as required

3 comments:

  1. It is a technical post but you have nicely described that how slings works. Your writing style is effective and easy to understand.

    Chain block

    ReplyDelete
  2. I am the author of most of the work on your website against which you are making financial gain. If you do not gain permission or remove it I will take further action. My site is non-commercial, I note you have placed content from marinediesels.info which is a commercial site, you are in breach of his copyright and as such ne may not be as generous in allowing you time to remove his work before taking further action.
    brian

    ReplyDelete