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A LOAD RESTRAINT GUIDE FOR DRIVERS and THEIR SUPERVISORS JUNE 2002. The Need for this Briefing Pack: We want you to go home to your family safely.
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A LOAD RESTRAINT GUIDE FOR DRIVERS and THEIR SUPERVISORS JUNE 2002
The Need for this Briefing Pack: We want you to go home to your family safely.
The driver, Mohammed Hussein , 31 years old, a father of one young son, was killed when he applied his brakes, and the 25 Ton mobile crane rolled forward and crushed his cab. The load rolled forward because:The wrong trailer was used - a normal 40ft flatbed trailer (with steel deck) instead of a lowbed trailer.Outriggers on steel-no friction. The chains and load binders ( ie the load restraints) were not strong enough to stop the load moving forward.-a chain binder broke under the strain.His company had only issued him with two chains andbinders - not enough for this heavy load. His company had not trained him in how to restrain or tie down heavy loads.
THE TRAILER Steel Decked Flatbed Trailer instead of a wooden deck lowbed trailer . Lowered Crane Outriggers, - but steel on steel adds very little friction, can slide easily.
The Load Binders The two chain binders each had a Safe Working Load (SWL) of 4.17 tonnes with a 1/2 inch chain. The binder , at the rear of the trailer , broke, under the braking forces, leaving the crane free to roll forward The binder at the front bent, and came loose from its fixing point.
The Chains Only two chains used, the smaller chain -3/8 of an inch- was used to prevent the crane moving forward. The second and much stronger chain was 1/2 inch (13 mm) thick, used wrongly, to stop crane rolling back. Apart from these two chains. No other effective load restraint was used to hold a 22 ton load in place.
To summarise this fatal accident: • The crane, weighing 22 Tonnes was inadequately restrained from moving in a forward direction • Inadequate chainage, not enough of them, wrong angle, wrong size. • No chocks at the wheels to add resistance/friction • Wrong Trailer, no protection for driver if things went wrong • Steel trailer deck meant steel crane outriggers added only minimal resistance compared to a wooden deck. • The managers, supervisors and drivers did not know how to transport and restrain such a load correctly. • Mohammed did not have to die.
ROLLER:Only two chains, no chocks, no restraint at rear, artic lock not in place. CRANE: Four chains, all almost straight across trailer, (little effect), one chain slack, no chocks, outriggers on steel WRONG! ROLLER 2 : Only two chains, one almost straight, artic. lock not in place, no chocks
FORKLIFT:Only one chain thru`tow hook, almost straight across, minimal restraint. no artic lock, no chocks. WRONG! Palletised CEMENT BAGS: Not against headboard, only thin rope around tarpaulin, there is nothing restraining the bags on pallets-only loose boards. Only the weight of the HIAB resting on frame is “securing” the load.
PIPES: knotted & tied web lashing, bent & broken side stakes. Overloaded. WRONG! REINFORCING STEEL MESH:Only loose thin rope used, load resting on side gate COMPRESSOR: Two chains, wrong angles & directions, no chocks.
NOW, let us look at how to transport and restrain loads, particularly wheeled loads and heavy plant CORRECTLY…. THE MAIN PRINCIPLES OF LOAD RESTRAINING PDO and SHELL use British Standards of Load Restraining applicable to ALL types of LOAD: • When a truck brakes, accelerates, changes direction or travels over rough road surfaces forces are generated on the load which are far greater than the friction between the load and the truck platform.The load will move if not secured.
Unless the load is secured by adequate restraining devices (chains, webbing belts, chocks, netting, twist locks etc), THE LOAD IS NOT SECURE. • The forces acting on a load during braking increase with the weight of the load and the heavier the braking (deceleration). • It requires much greater force to stop a load which has started moving - like a BatteringRam effect - than it does to prevent movement (restrain) in the first place.
LOAD RESTRAINT PRINCIPLES ONE FIFTH OF WEIGHT UPWARDS Rough Roads Braking FULL WEIGHT OF LOAD FORWARDS HALF WEIGHT OF LOAD REARWARDS Accelerating, or Reverse braking Cornering (Both Sides) HALF WEIGHT OF LOAD SIDEWAYS
TIE-DOWN:Load restrained using tie down lashings, eg 50mm wide web belts. Lashings are tensioned to clamp the load to the deck. Friction comes both from load weight and downward force of lashings. • FRICTIONis the resistance to movement between two surfaces. • Steel to steel, Low friction; movement is easy, can slip. • Steel on wood, Medium friction; • Steel on rubber load mat, High friction, more difficult to move CONTAINMENT: Such as tippers, tankers. Load contained with no securing devices necessary, within the body of the vehicle or container.
BLOCKED LOADS:Loads can be directly restrained by blocking against vehicle structure eg. Headboard, or drop sides. Still requires additional sideways, rearward and vertical restraint ATTACHED LOADS:can be directly restrained by lashings that provide all the necessary restraint. Friction of tyres/tracks on truck bed, and lashings provide restraint against sideways movement. Lashings provide restraint against rear, front and vertical movement. Chocks prevent forward and rear movement, particularly if chains are slack-”Belt and Braces”approach.
COMBINED TIE-DOWN and DIRECT RESTRAINT: Load prevented from moving forward by blocking against headboard , friction from load weight and lashing tension. Friction only prevents it moving rearward and sideways. Lashings prevent vertical movement FRICTION plus BLOCKING: Load restraint provided by friction force from weight of load, plus friction downward force of lashings, plus direct restraint from lashings attached to load.
CHAIN LASHING ANGLES: How wrong lashing angles can reduce the restraining effectiveness of the chain. Do Not Attach the chain high up on wheeled loads. Attach chain to obtain good angle-25 Deg. STRONGEST WEAKEST
CHAIN ANGLES SEEN from the SIDE VIEW: Recommended angle for direct lashing is approximately 25 degrees to the horizontal, ie to the truck bed, equals a slope of 1 in 2 , gives effectiveness of 90%. STRONG ! TRAVEL DIRECTION The length of the chain reaching down to the trailer deck from the securing point on the load should be at least twice the height measurement that the securing point is above the trailer deck:
CHAIN ANGLES SEEN FROM ABOVE, Chains that run directly back parallel to the side of the trailer are strongest in preventing forward or rearward movement. but mostly not practical. TRAVEL DIRECTION FRONT TAKE CHAINS preventing FORWARD movement as FAR BACK as possible, minimum length of twice the height of the fixing point on the load, to make as small an angle with the trailer edge as possible. MAXIMISE RESTRAINING! 45 Degrees at front of load 30 Degrees
CHAINS: • Use I/2 inch, (13mm chains), not smaller. Always carry a minimum of four chains (USE THEM!) and four binders . Minimum of two chains preventing forward movement. • Get the correct chain to load angles as per previous slides- both in height and direction-to maximise effect. • NEVER put chains straight across trailer between load and securing point. Totally ineffective. • KEEP CHAINS TIGHT, STOP AND CHECK: • On Blacktop roads -every 50 Kilometres • On graded roads - every 25Kms • The Driver is responsible for the securing of his load.
CHOCKS for wheeled equipment: • Chocks shall be used on EVERY journey that is 100% on blacktop. Chocks shall be secured. • Chocks are not essential for travelling off blacktop eg graded roads, where wheel bounce/pinch reduce even secured chock effect provided: • Sufficient chains are used to fully restrain the load • Parking brake/ transmission brake is ON, if equipment has 4WD option, put it into 4WD before applying brake! • If the above two conditions cannot be met, also use chocks. • Cycle hydraulic controls twice to relieve system pressure. • Can use oilfield trailers to carry all terrain forklifts • Larger plant, mobile cranes, dozers etc must always be transported on lowbeds
LOAD SAFETY • When dropping crane outrigger pads for transport do not lift the tyres from the deck. Use mats - rubber, plywood, or similar - under all outrigger pads on steel and wood decks -reduces wheel bouncing. • ALWAYS ensure the articulated lock bar is fitted on rollers, forklifts/ tool carriers etc which can articulate, prevents “folding” during transport. Put two chains thru`tow eyes, not just one. Prevents side movement.
LOAD SAFETY • TRACKED VEHICLES - transport on Low Beds : • Do NOT fix chains directly to the track plates of tracked equipment-bulldozers, side booms etc. Use anchorage points provided. Cross lash is best, as in this example. SHIPPING CONTAINERS : Only trailers fitted with twist-locks shall be used to transport 20ft and 40ft containers.
PIPE SECURING : • Use wooden dunnage positioned as shown. • USE 50 mm wide webbing belt, no knots. NOT CHAINS. • Side stakes, at least three per side • Large diameter metal pipe,- 24 inch and over -only two lashing/dunnage points otherwise trailer flexibility adversely affected. • Against the headboard, and not above the headboard.
BIG BAGS : • Transport within strong side cage as shown, or covered in cargo nets. • Can go two high with a central row-provided not overloaded. • When using cargo nets ensure ALL ROWS are covered by the nets. • Front Row against the headboard, [if trailer has a headboard-does not apply to oilfield trailers] .
NOTE to Managers/Supervisors: This presentation on load safety and load securing gives load securing principles and guidelines -- highlights and typical oilfield load examples only --these slides cannot possibly cover such a large subject in its entirety. Follow the guidelines, prevent further accidents due to faulty load securing. A more detailed PDO Spec. will be issued by end 2003. SHELL and PDO follow the British Department of Transport Load Securing Code of Practice which is on the PDO web: http://www.pdo.co.om/hseforcontractors/dts/documents/load-DETR-COP.pdfUser Name: pdohse01 | Password: contractor01 Another very good load securing guide with more pictures and diagrams is also available on the web : http://www.pdo.co.om/hseforcontractors/dts/documents/load-Aust-guide.pdfUser Name: pdohse01 | Password: contractor01