Thread: New Towing Guides

Originally Posted by Pedro_The_Swift

ADR's anyone?
"A safety connection device includes a trailer safety chain or cable as outlined in Australian Design Rule (ADR) 62 “Mechanical Connection Between Vehicles”. For trailers with an Aggregate Trailer Mass (ATM) up to 3500kg, ADR 62 requires compliance with Australian Standards AS 4177 “Caravan and light trailer towing components”. For trailers with an ATM over 3500kg, compliance with Australian Standards AS 2321 “Short-link chain for lifting purposes” is applicable.""

For clarification:
That is for the chain that is required to be permanently welded to the trailer
From ADR 62-00

3. APPLICABILITY
3.1. Applicability Summary
3.1.1. This national standard applies to the design and construction of vehicles as set out in the table below.


3.2. Applicability Table

Vehicle Category - ADR Category Code - UNECE Category Code - Manufactured on or After - Acceptable Prior Rules
Moped 2 wheels - LA - L1 - 1 March 1992 - Nil
Moped 3 wheels - LB - L2 - 1 March 1992 - Nil
Motor cycle - LC - L3 - 1 March 1992 - Nil
Motor cycle and sidecar -LD - L4 - 1 March 1992 - Nil
Motor tricycle - LE - L5 - 1 March 1992 - Nil
Passenger car - MA - M1 - 1 Jan 1992 - Nil
Forward-control passenger vehicle - MB - M1 - 1 Jan 1992 - Nil
Off-road passenger vehicle - MC - M1 - 1 Jan 1992 - Nil
Very light trailer - TA - O1 - 1 July 1991 - Nil
Light trailer - TB - O2 - 1 July 1991 - Nil
Medium trailer - TC - O3 - 1 July 1991 - Nil
Heavy trailer - TD - O4 - 1 July 1991 - Nil

ADRs 62-01 and 62-02 apply to vehicles and trailers manufactured after later dates. I can post them up if required.

Originally Posted by weeds

Pretty sure you have the 1.5 x ATM part wrong.....it's not in relation to SWL of the shackle but the maximum breaking load of the shackle (cannot quit think of the right terminology)....this mean means you only require a much lower SWL shackle.

You are correct it is Break load - is that the same as WLL?
I know that SWL is different and I think the actual "breaking" limit is 6X the rating.
Part Of QLD Rules
The Safe Towing Guide states, under Safety Chain Connections (Shackles, Pins or Bolts), that the Department of Transport and Main Roads “recommends that the shackles used should meet Australian Standard AS 2741-2002 “Shackles”, or another equivalent recognised standard, and have a break-load limit of the shackle is rated at least 1.5 times greater than the ATM of the trailer.

You can easily identify a shackle that meets AS 2741-2002 “Shackles” because they will be permanently marked with the following information:
<< The manufacturer’s name or trademark
<< Quality grade of the shackle, e.g. (“M” or “4”, “S” or “6”)
<< Working Load Limit (WLL) or Rating; and
<< Identification marking in order to correlate shackle to test certificate

Some additional points to note regarding shackle regulations in QLD:
<< Rated bolts, chain shackles or other suitable fittings (i.e. hammerlocks) may be used as devices for connection on safety chains providing the break load limit of the device is at least 1.5 times greater than the ATM of the trailer.
<< Generally, the break-load limit of a rated shackle will be six times greater than its work-load limit.
<< Pin diameter of shackle will be greater than the diameter of the main shackle body.
<< Same size shackles of different quality grades will have a different WLL (i.e. 6mm “S” grade shackle has a greater WLL than a 6mm “M” grade shackle).
<< Stainless steel shackles are unsuitable for trailer use due to the material’s general low resistance to bending stresses.
<< S” or “6” grade “D” Shackles bear similar characteristics to “S” or “6” grade Bow Shackles
<< Bow shackles provide for greater angular usage compared with “D” shackles.

And a link to the [ame]http://www.transport.nt.gov.au/__data/assets/pdf_file/0008/19646/vib13i-Light-Trailer-Safety-Chain-Shackles-Jan-2013.pdf[/ame] explaining the different grades and Break Load:

The confusing thing is how the shackles are rated and the different grades. I will have to check my shackles to see how they are marked, but from memory I have never seen a shackle with the Break load on them - either WLL or SWL.
The point I am trying to make is for the uninitiated they will not know what to look for and will probably choose the shackle that will fit the chain which may not necessarily be the correct rating - depending on the grade of the shackle as listed on the NT website.

If I am looking for the correct shackle for my trailer I need to look at the grading of the shackle and the WLL? According to the NT website a 5mm Grade S or 6 shackle with a 330kg WL and a 1987kg BL rating would be more than suitable for a 750kg trailer?