1. Coupling/Decoupling of Trailers
This work has been produced by DGL (Aust) Pty Ltd
This Learner’s Tool is about the skills and knowledge required to load vehicles at warehousing facilities of DGL (Aust)
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2. Before you get started 5/28/2018
It is important that you complete all sections in this learning tool as it has been designed so that
You can abide by the procedures of our organization.
You can apply what you have learnt in this package in your day to day activities
This Learning Tool is designed to be relevant only to DGL (Aust) Pty Ltd employees and only applied whilst employed with DGL (Aust) Pty Ltd
You may have already acquired knowledge in the area identified in this package as you may have completed some specialized training. Or you may have been working within the industry for some time. Should you identify any improvement opportunities in the information contained in this package or have difficulties completing the package please contact
National Training and Compliance Manager
DGL (Aust) Pty Ltd
PO BOX 1594
EAGLE FARM QLD 4009 Ph
Fax
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3. Coupling to Trailer
Ensure that it is clear and safe in area, before backing under trailer.
1. Align the Prime Mover with the Trailer.
2. After pulling handle out to open jaws, check turntable
and make sure jaws are open. This means look at rear of
turntable, if at night use a torch.
WHY:
This ensures that driver has made the coupling procedure safe and ensures outcome of procedure will be without failure.
Hazard:
Damage to both Trailer and Turntable. Not correctly done will cause expensive repairs, when coupling.

4. Coupling to a trailer

5. Coupling to Trailer
3. Chock trailer wheels, to prevent trailer movement.
4. On backing up to trailer stop before turntable goes under skid plate of trailer, examine that trailer will contact turntable approximately 15cm up from front of tang.
5. Continue reversing truck underneath trailer until you hear jaws snap shut .
WHY:
Ensures correct coupling between trailer and turntable.
Hazard:
Height difference too high, service and supply
connections on trailer damaged.
Too low and jaws of turntable and Kingpin of trailer WILL
be damaged.
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6. Coupling to Trailer
6. Apply park brake, get out of truck & visually inspect that turntable jaws are locked shut & secondary lock is in position.
Handle fully engage in.If you can see that it isn't all the way in, pull forward and do the procedure again.
7. Raise trailer legs a couple of mm off ground. Do a tug test by selecting first gear and then trying to drive forward, do not accelerate excessively, just a gentle tug.
WHY:
Ensures turntable has locked trailer to Prime Mover & Tug test confirms visual inspection.
Hazard:
Trailer support legs bent. Trailer could be “dropped”, damage to Prime mover guards, taillights, airlines, electrics and customer product if loaded.
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7. Coupling to Trailer Important note
Once the release leaver has been pulled and the jaws on the turntable has been released they can only be locked back in after the trailer pins has completely cleared the turntable and then the prime mover is reversed back in. They CAN NOT BE MANUALLY RELOCKED by manually releasing the locking lever.

8. Coupling to Trailer
8. Connect both service and supply airlines, first ensuring they are serviceable and not damaged. Turn female fitting, so hole is not aligned with the flat spot on fitting
and actually locked after twisting ¼ turn.
9. Wind up trailer support legs. Apply service trailer brakes and perform second tug test. Put hazard lights on walk around vehicle and check that all electricals are working, visually inspect trailer for any faults.
WHY:
Ensures air supply and electrical power to trailer, ensures braking system on trailer is operational and trailer support legs are not damaged during vehicle operation.
HAZARDS:
Air supply faulty/ trailer brakes not working, electrical system not working and clearance/brake /number plate lights and indicators not operational.
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9. Coupling to Trailer
10. Release park break. Allow air supply to charge trailer
brake system.
11. Apply service trailer brakes .
12. Perform Tug Test again .
13. Park truck and trailer and put hazard lights on –
walk around vehicle and check that all electricals are
working.
WHY:
To ensure trailer braking system is operational and ensure trailer is coupled to Prime Mover.
HAZARDS:
Trailer brake system is faulty. Trailer was not coupled completely and tug test fails:- trailer drops.

10. Decoupling of Trailers
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11. Decoupling from Trailer
1. Position trailer in drop off position.
2. Check position of Prime Mover.
3. Check that both prime mover and trailer are in a straight line
and on ground level.
4. Chock wheels on trailer & wind legs down, determine if legs of
truck need to have additional load bearing supports
(Asphalt/bitumen is always soft ground!).
5. Uncouple Air Lines and Electrical connection, fitting them to
blanks, or if not fitted where they will not be damaged.
WHY:
Prevent trailer sinking into soft ground .
HAZARDS:
In decoupling trailer/Prime mover damage to both if ground is soft, either whilst decoupling or when next Prime Mover attempts to couple

12. Decoupling from Trailer
5. Release turntable, move Prime Mover forward enough to
ensure Kingpin clears past Jaws and secondary lock,
before deflating airbags and completely pulling away
from trailer.
WHY:
Prevent damage to Trailer, turntable & Prime Mover when decoupling
HAZARDS:
Potential to damage both Kingpin and Turntable if deflation of airbags occurs before moving forward away from trailer with Prime Mover.

13. Learnings from previous incidents
Incident – Operator was conducting a trailer change over
Drove the prime mover our from under the trailer and the trailers legs sunk into the road
Root Cause – Operator did not follow SOP for Decoupling a Trailer, No timbers were placed under the legs of the trailer prior to unhitching the trailer, Wet weather conditions
Key Learnings – All road surfaces to be treated as a soft surface, Coupling & Decoupling should be followed to the letter as per the SOP

14. Test your knowledge
Through the following slides you will be asked an number of questions to show that you have understood the content of this learning tool
Please record your answer on the training form F-260.
You will be required to submit the answers to the DGL HSEQ unit
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15. Question 1 When about to couple to a trailer, what should a driver do?
a) Nothing just back under and hope for the best.
b) Alight from Truck and check height of trailer & prime
mover, and ensure turntable jaws and secondary
lock are open.
c) After checking turntable is open, back in from any angle and couple to trailer.
d) Quickly glance to see Prime Mover will fit under
trailer and back under.
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16. Question 2 How many Tug tests are to be performed? a) One b) None
c) As many as you fell is necessary.
d) Three,
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17. Question 3 When should bearers be used to support a trailer?
a) When ever you think someone is watching you.
b) If decoupling is occurring on uneven ground.
c) Whenever decoupling on soft ground including
Asphalt/Bitumen.
d) Never no need to.
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18. Question 4 Why is the second Tug test performed when I’ve already done
a) Because it tests both the trailer brakes are working as well as a safety tug test.
b) Procedures say to do it.
c) Just the way the procedure is.
d) No idea.
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19. Question 5 Where when uncoupling, should the Airlines and
Electrical lines be stowed?
a) No where special, anywhere easy to reach is good enough.
b) Attach to fitting blanks or stow where they will not be
damaged if blanks are not fitted.
c) It does not matter where they put.
d) Put them around exhaust pipe so you know where they are.
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