In early 2018, Avweld’s sales engineer David Camilleri and Loctite’s business development manager Vaughan Bartleson were approached by Stuart Daly, the maintenance supervisor at Holcim Australia’s Werribee Quarry about an issue with the extremely short life of piping used in the dewatering wash process. The piping is used to feed 7mm minus concrete aggregate, which derives from a very abrasive Western Plain basalt.
Holcim had tried a range of options, with limited success. In the most abrasive positions, standard 152mm (6”) steel pipe elbows could last as little as three to four weeks. Rubber-lined pipes only increased the life to five weeks and didn’t justify the increase in cost.
It was evident the constant pipe change-outs were causing significant downtime and labour costs to the plant. Camilleri and Bartleson provided two solutions: patch repair and replacement.
For the patch repair of holes in old rubber-lined pipe elbows, the recommended solution was for the Loctite Flex 80 polyurethane rubber repair compound, which is typically used for repairing damaged conveyor belts. The exterior was patched with Loctite’s fast curing wearing compound, which is typically used to patch worn liners. The pipe repaired using this method was installed and lasted for eight weeks.
The option presented for new pipes for longer life extension and so Avweld’s AbrasaPipe hardface weld overlay pipe was introduced. With chrome carbide hardfacing overlay up to 9mm thick, the AbrasaPipe provides solid abrasion resistance, and can be supplied in either straight pipes, elbows or reducers. For the pricing of the pipe, the Holcim team had an expectation that this product would last between three and six months. At time of writing, the trial pipe has been installed for 14 months and is still performing well.
This massive increase in life has provided considerable labour and material savings for the quarry and resulted in the AbrasaPipe being standardised as the material of choice for abrasive pipe applications.
In addition to the obvious cost savings, safety was also a consideration in switching to the AbrasaPipe. The manual labour involved with replacing pipe work in difficult locations, sometimes high off the ground, provides significant hazards. The reduction of this high risk change-out task by a factor of more than 10 times is considered an excellent safety benefit.
Avweld, which is a large scale repair and maintenance company based in Melbourne, is continuing discussions with the quarry about further cost savings and safety improvement possibilities. Its focus is on using its experience in wear resistant and other advanced materials to increase the life of quarry plant and equipment. Its other products and services include the AbrasaPlate wear plate, repair of crushers, shaft and journal repairs, general hardfacing, large scale machining and grinding and thermal spray. Avweld is a certified Loctite composites applicator.
Through its welding supplies division Alloys International, Avweld also supplies wires and electrodes for maintenance and repair, including low hydrogen electrodes, hard facing, tungsten carbide and exotic materials.
Avweld and Alloys have technical sales staff in all areas of Australia, with expertise in material selection and advice for life extension of high wearing components.
Source: Avweld Australasia