Safety Chain and Holders to 22t
Although most trailers under 3.5t comply with the National Code of Practice, we found that most trailers over 3.5t do not comply. Most trailer manufacturers are unaware until safety was brought to their attention. It would not be unusual if your rig is over 3.5t and does not have Grade 80 chains.
Galvanised Chain and shackles are illegal on all trailers over 3.5t.
AS4177.4 – 2004
Supports Galvanised Safety Chain to a Max 3.5t.
Use of Galvanised Safety chain over 3.5t is illegal.
The problem exists with OEM installing Galvanised Safety Chain on Caravans and Trailers over 3.5t when NO alternative was available. (alternative is NOW available on links below)
Supports Herc-Alloy Safety Chain on caravans and trailers over 3.5t.
Importantly, chain holders are welded to trailer and towbar. These chain holders must contain a high tensile pin of 4140 Grade Steel.
Call Bruce or Mike on 07-33483822 if you require more information.
I invite you to print this email and show it to your local Vehicle Inspection Officer for accuracy. It will generate sales for you and me.
If you feel this information is erroneous, please let me know firstname.lastname@example.org
Some Technical Details You’ll Need
Your trailer’s safety chain holder must be fitted in accordance with Australian Standards—either AS 4177.4-1994 or AS 4177.4–2004.
Trailers over 3.5 tonnes ATM must have two safety chains made from steel of a minimum 800 Mpa breaking stress. Both of these need to conform to the mechanical properties of Grade-T chain as specified in AS 2321-1979 ‘Short Link Chain for Lifting Purposes (non-calibrated) or Australian Standard AS 2321–2006 Short Link Chain for Lifting Purposes. Each chain must be sized such that the minimum breaking load exceeds the ATM.
How do I select the correct Dee or Bow Shackle?
Rated Dee shackles are tested and rated according to AS2321 Short Link Chain for Lifting Purposes. However, trailer chain and shackles are used for towing. Therefore, we need to look at the equation.
WA Ci-199C is the document that contains the Dee rated and Safety Chain information
The marking on a Rated Shackle are the Safe Working Load Limit (WLL)
The Breaking load limit (BLL) for rated shackle is WLL x 6, Example, a 1 tonne rated Dee Shackle has a BLL of 1t x 6 = 6t (Breaking Load Limit)
Calculate the ATM as follows, BLL / 1.5 = 6t / 1.5 =4t
Therefore a 1t Dee Shackle can be used on trailers up to 4t. Please see the following table for more ratings
0.75t Dee Shackle = 3t ATM Caravan
1t Dee Shackle = 4t ATM Caravan
1.5t Dee Shackle = 6t ATM Caravan
2t Dee Shackle = 8t ATM Caravan
Note: The design of the attachment to the drawbar must have sufficient load capacity to match the rating of the required chain.
Couplemate sells the quality trailer and caravan spares throughout Australia—covering the Northern Territory, Western Australia, South Australia, Victoria, New South Wales, and Queensland. We also ship products via Australia Post Air to New Zealand.