Safety Chain Testing
Safety chains are components required to be present on a number of trailer types in Australia. Their function is to keep a trailer attached to the towing vehicle in the case of separation of the coupling. Manufacturers of towbars, trailers and the chain itself must be aware of the required standards when supplying their components to the road vehicle market in Australia.
What are the ADR requirements for safety chains?
ADR62/02 details the requirements for safety chains, which defers back to one of two Australian standards for the chain itself depending on the rating of the trailer. For towing requirements up to 3500kg, the chain must comply with AS 4177.4-2004, with two chains (each rated to the ATM on their own) required for any trailer about 2500kg. For all towing requirements above 3500kg, the chain must comply with the lifting equipment standard AS2321-2001 which refers to the necessary Grade T requirements for short link chain.
Safety chains must be fitted to every rigid drawbar trailer, excluding converter dollies. This includes both light and heavy trailers.
Safety chain attachment points also must comply with the requirements of ADR62/02. The strength requirements are the same whether the attachment point is on the towing vehicle or the trailer; the attachment point must be capable of withstanding a load in Newtons of 9.81 x ATM (Aggregate Trailer Mass) in the longitudinal tension direction and 0.5 x 9.81 x ATM in the vertical direction. The Department of Infrastructure in their guidance note "What is an Approved Calculation for AR62/02" have clearly stated that safety chain attachment points must be subject to a physical test:
"Requirements for safety chain attachment points are in ADR 62/02 clause 13.4 for towbars, and clause 14.4 for trailer drawbars. In both cases the ADR does not allow approved calculations to demonstrate compliance. Therefore, testing by an approved RVS testing facility is required."
Included in the requirements for safety chain attachment points is the associated rigging equipment that may be used to affix the chain to the trailer or vehicle. This includes items such as D-shackles and hammerlocks. It should be noted that many of these components are provided with a working load limit (WLL) which can include a significant safety factor on the actual breaking strength. ADR62/02 only requires the component to withstand the loads without failure, therefore a 1500kg WLL rated shackle may be suitable for use in a heavier application.
Our safety chain testing services
BTT Engineering has tested a broad range of safety chains and their attachments and can assist clients with demonstrating compliance via testing through a number of our services provided.
Load testing
BTT Engineering can conduct testing on safety chain complying to AS4177.4-2004. As part of the requirements for this standard, proof testing where the visual inspection displays no damage must be carried out along with destructive testing where the chain must achieve a certain amount of elongation prior to failure above the minimum breaking load.
Safety chain attachment point testing
As stated above, safety chain attachment points must be subject to a load test from an approved RVS testing facility. For us to carry out this testing, clients can provide a sample for testing including a short section of drawbar/towbar and the chain attachment methods. The acceptance criteria for this testing is that after each of the required loads is applied separately for at least 10 seconds, the attachment point must not show any residual deformation that would interfere or degrade the function of the assembly or any breaks, cracks or separation of the components. Depending on the performance of the sample under testing, it may be suitable to visually inspect or non-destructive testing via dye penetrant may be required.
Compliance with ADR 62/02
As an RVS approved testing facility, BTT Engineering is able to demonstrate compliance to ADR 62/02 through testing. For clients looking for a fast and easy solution to their chain attachment requirements, BTT Engineering has a library of pre-tested designs available for supply which can be purchased and implemented immediately. For manufacturers of chains or attachments, BTT Engineering can complete a component type approval (CTA) ROVER application to allow manufacturers to demonstrate compliance with the applicable standards through holding a CTA.
How long does the safety chain testing process take?
The actual physical test component of safety chain and chain attachment testing will take anywhere from a couple of hours to half a day to complete. A sample must be provided prior to testing being carried out and upon successfully finishing testing on a sample a detailed test report will be generated detailing the results in line with the requirements of an RVS test facility. From start of testing to completion of reporting the timeframe is expected to be 2-3 weeks depending on the amount of samples tested and our workload at the time.
Does a welded chain link need testing?
Yes! Although a safety chain itself may be compliant to AS4177.4-2004, there is no guarantee that welding it to a drawbar will result in the weld or drawbar having enough strength to withstand the necessary loads. BTT Engineering has tested welded chain attachments in the past which have not passed ADR load requirements - manufacturers need to ensure that if they are using this method of attachment there is still test evidence to support it.
Why Choose BTT Engineering for safety chain testing?
BTT Engineering is a registered test facility under the RVS legislation and is approved to provide ADR62/02 testing services, meaning that test results are valid for any of a client's ROVER requirements. We have an in-house test rig enabling us to schedule in testing without any third party delays and can complete testing on a broad range of designs and samples. Our equipment is regularly inspected, calibrated and serviced ensuring that the results obtained are of high accuracy. Clients can be assured that our testing service will be completed in a prompt and efficient manner, minimising any delays in getting a ROVER approval.
Related safety chain testing services we can help with
How much does safety chain testing cost?
Safety chain and chain attachment testing costs depend on the design and quantities samples provided. Manufacturers and suppliers looking to have multiple designs tested can expect this to be conducted at a discounted rated. Need help with safety chain testing? Contact us for an obligation free quote.