Electricity and Control February 2024

PLANT MAINTENANCE, TEST + MEASUREMENT : PRODUCTS + SERVICES

Condition monitoring and predictive maintenance in mining

Specialist condition monitoring company, WearCheck, again showcased its range of mining-related predictive maintenance techniques, products and services at the 2024 Investing in Africa Mining Indaba in Cape Town’s ICC from 5 to 8 February 2024. Technical manager, Steven Lumley, and a team of technical experts from WearCheck were on hand to demonstrate the company’s world-class technolo gy-based solutions. Says Lumley, ‘Africa Mining Indaba gives us the op portunity to introduce our unique condition monitoring

wedges had deteriorated significantly over time. We con sequently requested the M&C workshop in Cleveland, Johannesburg, to provide partial discharge treatment of the stator coils and to manufacture the stator wedg es that needed to be replaced,” said Eugene Lottering, General Manager, M&C Zambia. To ensure all the work complied with international standards, M&C also sent a senior technician from Johannesburg to assist the local team on the contract. “Our team is well experienced in how to approach and action the different stages throughout the overhaul of such motors. We have successfully completed various medium voltage overhauls up to 4 650 kW. The motors were no-load tested at 11 kV with exceptionally good results and the customer then gave us the go-ahead to commission the motors,” Lottering added. He highlighted that “Installing them on site turned out to be a complicated procedure, especially the alignment of the motors to the compressors.” The motors were finally tested on load, recording sat isfactory vibration levels of below 1.34 mm per second. “The motors were successfully installed and com missioned three days before the scheduled deadline for completion,” Lottering noted. a team of specialised diagnosticians, who advise on a course of remedial action, if it is required. Additional predictive maintenance techniques of fered – which are applied based on the machinery and components being monitored – include asset reliability care (ARC) services, transformer chemistry services and advanced field services (AFS) such as non-destructive testing (NDT), technical compliance (TC) and rope con dition assessment. The company also offers lubrication enabled reliability (LER), providing clients with bespoke solutions to ensure their lubrication systems are well managed, efficient and cost effective. WearCheck’s service offering also includes water analysis through Set Point Laboratories, which analyses the quality of wastewater, groundwater and surface water in areas surrounding mining and exploration sites. The water division caters to various needs. For exam ple, ensuring that effluent/wastewater is compliant with municipal by-laws and environmental safety standards is essential for the safe disposal of wastewater into streams and rivers. Additionally, ground and surface water quality anal ysis allow for determination of water safety for use on equipment, drinking, washing and other purposes. For more information visit: www.wearcheck.co.za

services to potential new customers, and to present our newest techniques to existing clients. We always enjoy catching up with our ‘family’ of the many familiar players in the African mining arena with whom we have been interacting as a company for the past 47 years.’ WearCheck’s core service is the scientific analysis of used oil, fuel and other fluids. This entails analys ing fluid samples for trace particles, which indicate which component is suffering unusual wear patterns. The test results are assessed by

Roger Henwood, WearCheck technician, conducts rope testing analysis.

Quick turnaround on overhaul of compressor motors

In August 2022 Marthinusen & Coutts Zambia was re quested by a smelter based in the Copperbelt to provide an in-country repair solution on two critical 4.5 MW com pressor motors. It was given only three weeks in which to overhaul and recommission the motors. The scope of work involved the dismantling, cleaning and assessment of all parts, dynamic balancing of the rotors at operating speed using M&C Zambia’s in-house 12-tonne balancing machine, supply of new bearing as sembly parts, assembly of the motors and no-load test ing and laser aligning the motors on site. “On dismantling both motors we identified that the stator coils indicated partial discharge and the stator

Dynamic balancing of the rotors at operating speed was done using M&C Zambia’s in-house 12-tonne balancing machine.

For more information visit: www.mandc.co.za

26 Electricity + Control FEBRUARY 2024