The New Zealand Transport Agency has called for the urgent inspection of 1800 heavy vehicles requiring their towing connections to be immediately assessed.
The alert follows the discovery of towing connection cracking in three different truck and trailer units.
In the first instance, the NZTA has concerns about skid plate failures on refrigerated semi-trailers.
The NZTA issued its first safety alert after the skid plate on a MaxiTRANS refrigerated semi-trailer failed due to internal structural cracks that resulted in the trailer partially disconnecting from the towing unit. Several other units have had similar problems with various degrees of severity, one being found in the pre-inspection stage before the driver entered the vehicle.
This problem is not necessarily a problem with MaxiTRANS trailers but rather, as the NZTA say, all refrigerated trailers ought to be checked more frequently for fatigue and cracking. They recommend performing borescope inspections every 50,000km after 300,000km travelled.
MaxiTRANS said that they are working closely with the NZ Transport Agency and that the alert applies to other brands of refrigerated semi-trailers also, not exclusively to them.
In the second alert, the Transport Agency identified deficiencies in towing connections certified by Nelson-based business Peter Wastney Engineering Ltd.
Following multiple failures in both drawbeams and drawbars certified by Peter Wastney Engineering the NZTA has been prompted to conduct independent reviews of each affected unit. The independent enquiry found that the affected towing connections were not adequately designed to carry the loads for which they had been certified.
As a result, the Agency is calling for all units that have been worked on by Peter Wastney Engineering to be inspected by another heavy vehicle specialist certifier for any faults, and that any units with faults be discontinued immediately.
In addition, the NZTA have also recommended that all certification areas (log bolsters, load anchors etc.) that have been certified by Peter Wastney Engineering Ltd. Be re-assessed by another HVSC and that any deficiencies be immediately dealt with before the unit returns to the road.
Kelvin Barclay, Heavy Vehicle Certifying Engineers group at Engineering New Zealand, told RNZ the two alerts were unprecedented in a certification industry set up only in the late 1980s and work was going on to get operators to cut inspection portals to check for cracks.
For the safety of drivers, and of other road users it is important that operators get their vehicles regularly inspected and to encourage drivers to be vigilant in their visual inspections.