Document ID: chunk:federal_register_of_legislation:F2007C00494:body:0:p9
Version: federal_register_of_legislation:F2007C00494
Segment Type: other
Provision Reference: 
Character Range: 26017–29337

tension
and compression(N) = 0.5  x 9.81 x 'ATM'(Kg);
14.2.2.2.                    For 'Convertor Dollies' or trailers over 23.5 tonnes 'ATM', the following minimum static forces separately applied at the intended 'Coupling' centreline:
14.2.2.2.1.              longitudinal tension and compression = 350kN; and
14.2.2.2.2.              transverse thrust = 120kN; and
14.2.2.2.3.              except for hinged 'Drawbar' trailers vertical tension and
compression = 120kN
14.2.3.                          The strength of a 'Drawbar' can be demonstrated for loads as per clause 14.2.2 by 'Approved' calculation procedures where the calculations take into account both strength and fatigue resistance.
14.3.                                'Drawbars' Safety Chain Attachment Requirements.
14.3.1.                          Safety chains must be permanently attached to the trailer.
14.3.1.1.                    Shackles are not permitted.
14.3.2.                          For trailer up to 3.5 tonnes 'ATM', the safety chain attachment can be by welding.
14.3.2.1.                    the weld must extend around 50% of the circumference of the link and the adjoining link must have free movement.
14.3.3.                          For trailer over 3.5 tonnes 'ATM' safety chain attachment must not involve welding or deformation of the chain.
14.3.4.                          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'.
14.3.5.                          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:
14.3.5.1.                    longitudinal tension(N) = 9.81 x 'ATM'(Kg); and
14.3.5.2.                    vertical load (N) = 0.5 x 9.81 x 'ATM' (Kg).
14.4.                                Safety Chain Requirements
14.4.1.                          Safety chains must be affixed to a substantial portion on every trailer which is not fitted with an 'Emergency Brake System' in accordance with the Australian Design Rule 38/02 "Trailer Brake Systems", and on every 'Drawbar' of a Rigid drawbar Trailer except a 'Converter Dolly'.
14.4.1.1.                    Trailers having an 'ATM' over 2.5 tonnes must be fitted with 2 safety chains for connection to the towing vehicles.  Each safety chain must meet separately the strength requirements of clause 14.4.2 or 14.4.3.
14.4.2.                          For trailers up to 3.5 tonnes 'ATM', the safety chain must comply with Australian Standard 4177.4 -1994 "Safety Chains up to 3500 kg" or as amended from time to time.
14.4.3.                          For trailers over 3.5 tonnes 'ATM', the safety chain must be made from steel of a minimum 800 MPa breaking stress and conform to the mechanical properties of Grade T chain as specified in Australian Standard 2321-1979 "Short Link Chain for Lifting Purposes (non-calibrated) or as amended from time to time; and must be of a size corresponding with the 'ATM' of the trailer shown in Table 1.

'Aggregate Trailer Mass'  Chain Size     Minimum Chain Breaking