Trailer saftey chains

[Stuart]

I went into a specialised air and lift shop today with the intention of buying some standard safety chain for my new trailer. When I asked the guy for some heavy chain he asked what for. I told him it’s for a boat trailer that will be over 2t. He told me that you need a certified chain. What the hell is that mate? Well, it’s a certified chain that has been pre tested and stamped with the Australian standard and rating. Didn’t even know this stuff existed, but he showed me the book and the stamp on each and every link. I also asked him if I was to be involved in an accident and the chain snapped what would happen with my insurance. He said that the insurance company would then go the chain manufacturer. I also asked the guy how many boat trailers are getting around with un-certified safety chains, he said most. In this day and age of dodgy insurance companies it may pay to have a close look your safety chain as a week link in your insurance. I thought this was very interesting and quite understandable.

Stu

[Alchemy]

http://www.transport.qld.gov.au/resources/file/eb849042963ccb6/Safe_towing_information_V2.pdf

[Hydrotherapy]

Not just the chain, the shackles need to be certified also.

[Charlie]

“Transport chain” is actually fairly common, we used to do some fairly dogdy things with quarter inch chain and 4wd’s, most people have wisely moved to 7.3mm nowadays which should have a safe working load of 2 ton. I’d be interested to hear his suggestion for affixing it to he trailer, I reckon it’s more likely to rip off than break

[tunaticer]

I wonder how far an insurance company would go with avoiding a payout??

If by chance you had a tow hitch failure and that caused an accident and the safety chains did the job they were intended to do but were not certified, would they deny the claim?

Similarly so, even if the hitch and chain did not fail but you had a major accident and they found the safety chains were not certified, would that be grounds enough to deny the claim?

I think that if the chain was suitably heavy enough to do the job safely (to keep the trailer and its load connected to the tow vehicle) they should have no instance of denying the claim.

There are countless trailers out there with 12mm galvanized chain in use as safety chains that would most likely be well in excess of the braking strain of 8mm certified chain.

Technically speaking if the chain is welded to the chassis then the chain is no longer certified because the welded links will be heat stressed and possibly damaged with undercut and sub surface cracking. Do they go to the extremes of how it is attached as well?

Jack.

[FNQCairns]

Technically speaking if the chain is welded to the chassis then the chain is no longer certified because the welded links will be heat stressed and possibly damaged with undercut and sub surface cracking. Do they go to the extremes of how it is attached as well?

Jack.

Thats interesting and as the regs will not allow them to be bolted....

cheers fnq

[Stuart]

Its all news to me, I didn’t even know you could get certified chain. I thought chain was just chain; it’s all the same stuff, apparently not. I also asked the guy about welding it and he said no worries. But as mentioned that could lead to other problems, but then as FNQCairns said, you aren’t allowed to bolt it either. So that being the case what are you to do? I wouldn’t be surprised what lengths insurance companies go to these days. I think it’s safe to say we have all seen some very petty nock backs. I thought I would put it out their as I want to over build this trailer rather than just on legal. Also picked up a 3.5t coupling yesterday, now that’s a heavy bit of gear.

Stu

[Hydrotherapy]

This is a C&P from VSB1, note that a 'pig' trailer is is defined as any trailer with the axle in the centre of the load (most trailers).

12.3 Drawbars Safety Chains
All pig trailers with rigid drawbars and any other trailer without breakaway brakes must be fitted with safety chains complying with the following:
trailers of ATM up to 2.5 tonnes must have at least one safety chain complying with AS 4177.4 -1994 or as amended from time to time;
trailers of ATM over 2.5 tonnes and up to 3.5 tonnes must have two safety chains of designation of 3500 kg complying with AS 4177.4-1994;
trailers of ATM over 3.5 tonnes and up to 4.3 tonnes must have a chain size of at least 7.1 mm a minimum chain breaking load of 6.4 tonnes be made from steel of a minimum 800 Mpa breaking stress and conforming to the mechanical properties of Grade T chain as specified in AS 2321-1979 'Short Link Chain for Lifting Purposes (non calibrated). trailers of ATM over 4.3 tonnes and up to 4.5 tonnes must have a chain size of 9.5 mm a minimum chain breaking load 11.6 tonnes be made from steel of a minimum 800 Mpa breaking stress and conforming to the mechanical properties of Grade T chain as specified in AS 2321-1979 'Short Link Chain for Lifting Purposes (non calibrated) or as amended from time to time
(Effective from July 1998)12.4 Drawbars Safety Chain Attachments
The chain must be permanently attached to the trailer shackles are not permitted.
For trailers up to 3.5 tonnes ATM the safety chain attachment can be by welding. The weld must extend around 50% of the circumference of the link and the adjoining link must have free movement.
For trailers over 3.5 tonnes ATM safety chain attachment must not involve welding or deformation of the chain. Suitable pin-lock couplings should be used.
The safety chain attachment must be located as near as practicable to the coupling and where 2 points of attachment are required they must be mounted one on either side of the centreline of the drawbar
The safety chain attachment must withstand the following minimum forces separately applied without incurring either any residual deformation that would interfere or degrade the function of the assembly or any breaks cracks or separation of components
Longitudinal tension (N) .. 9.81 x ATM (in kg)
Vertical Load (N) ..... 0.5 x 9.81 x ATM (in kg).

[BM]

Looking at the above I would say above 3.5ton is the important or more emphasized section, since they are not allowing the chain to be welded.

I would be surprised if any of the major manufacturers are building their trailers incorrectly and I'd be equally surprised if they required certified chain. There is no reference to certified chain in the above and the relevant AS can't be read unless you purchase it.

Every trailer manufacturer must abide by the trailer guidelines handbook when building trailers. I have the Vic handbook and it very clearly spells out how trailers must be constructed in all facets.

If anyone has the relavent section of the standard then post it up for us to read the precise requirements.

Cheers

[Hydrotherapy]

Don't you just love our federal gov, we pay their wages and they charge us to view OUR regulations.

Here is a pirated (not paid for) portion of AS4177.4-2004

http://img.photobucket.com/albums/v259/Dunaruna/untitled-2.jpg

[jeffrey_h]

I think one of the main reasons that a trailer will 'part' from the ball is when the latch has been locked up while you put the coupling onto the ball, then forget to engage it before moving.


This happen to me years ago with a loaded box trailer that was put onto my car by my employee, I didn't check and some distance down the road, over a bump and it jumped off. Had to winch it back up with the jockey wheel to get it back on.


If this is on your trailer hitch you could consider cutting the latch part off to avoid the possible problem of it been left up.


With my big boat trailer I also have a stainless steel wire, which is longer than the shackled chain, locked to the car to stop thieft. On the tinnie it's a second small chain locked on.


Jeffrey