Couplers facilitate the connection of electrical cables to mobile mining equipment. “Given that they are traditionally manufactured from brass, leaded gun metal or stainless steel, the extremely high weight-to-value ratio of these critical components presents a high theft risk,” explains Donovan Marks, Director at Proof Engineering. 

The cost of replacing stolen couplers is often further exacerbated by subsequent downtime and production losses. In an endeavour to come up with a cost-effective solution for customers and end-users, Proof Engineering embarked on a three year research and development programme and pioneered the ProAlloy zinc coupler. This revolutionary unit presents a three-in-one solution for industry – reduced theft risk, lighter weight and lower cost.





Instead of the traditional materials, the ProAlloy is manufactured to specification from a zinc, copper and aluminium mix which holds no resale value thus earning the name, ‘non-theft material’. “The aluminium contaminates the mix, significantly decreasing the value from approximately R35/kg down to R6/kg. Furthermore, it cannot be sold for scrap.” 

The patented non-theft ProAlloy material not only also makes the coupler 33% lighter in weight compared to their brass equivalents but also presents a more affordable alternative.

Marks points out that due to the fact that it is a unique patented alloy, material movement can be controlled between manufacturer, supplier and end-user. 

The ProAlloy coupler demonstrates material integrity, retains its machinability and remains completely malleable. The Zinc product has undergone stringent corrosion tests conducted by Mintek against brass in mining water and results showed that there is no corrosion affect. Marks affirms that the addition of a newly developed additive has improved the metal strength of the coupler even further, retaining its competitive edge.

Proof Engineering closes the loop by buying back the metal from customers at R15/kg.To ensure very little or no impact on the environment, the company recycles the metal through re-melting which is in line with the company’s commitment to a cleaner environment. 

The ProAlloy couplers have been successfully tried and field-tested by a number of blue chip mining houses. This has led to the manufacture of ProAlloy plugs and sockets that provide end users with the same benefits as the ProAlloy couplers. “The material may also have potential applications in components other than electrical couplers, such as switches, housings and flameproof glands,” concludes Marks.

Making its mark within the Southern African mining and industry markets, Proof Engineering, a Hudaco company, is a specialist supplier of world class components, equipment and systems to the mining, marine, industrial and general engineering sectors in Southern Africa for over 45 years. It is also a leading manufacturer and supplier of a wide selection flameproof and explosion proof products which includes an extensive range of flameproof glands. Utilising the latest technology in all its electrical offerings, the company’s vast product range comprises plugs, sockets, adaptors, connectors and couplers for both underground and surface mining applications. Certified Proof Engineering technicians are readily available to provide superior specialist services and support to customers and end-users around the country with services extending to the terminating of plugs and couplers onto cables.