May 18, 2012
Supplier questions utility’s maintenance procedures, Eskom denies claimsBack
Eskom|Sekela Bearings|South Africa|Arnot Power Station|Arnot Station|Grootvlei|Grootvlei Power Station|Split Bearings Supplier|Malusi Gigaba|Steinhobel|Warwick Steinhobe|Cast Iron|Eskom|Floor Vibration
© Reuse this
Sekela Bearings technical manager Warwick Steinhobel says bearing consumption at the utility’s Arnot power station is unusually high, owing to floor vibration that causes damage to the cast iron bearing components used in the seal-air fans.
“Seal-air fans are two-stage fans and the bearings sit between the impellers, so you cannot strip it, which is why split bearings are used,” he explains, adding that the bottom part of these bearings cannot be changed, as it cannot be removed from the fan.
Steinhobel alleges that the cast iron bearings base used in the Arnot station’s seal-air fans becomes damaged or breaks, damaging the rest of the bearing parts; however, as Eskom is unable to replace the entire bearing, it replaces only the top part.
“Eskom is fitting brand-new bearings to damaged cast iron, which is why the bearings do not last, resulting in the high bearings consumption,” he claims.
He states that Sekela Bearings has developed its SNQ support bearings to mitigate this problem at the power station.
The SNQ support bearings will, unlike standard support bearings, enable the replacement of the entire bearing, says Steinhobel.
“We believe that, with our product, Eskom’s bearings consumption will be reduced dramatically, which we believe currently amounts to about 15 to 20 bearings a year for Arnot.”
Sekela Bearings has approached the power utility with this solution, but says the utility has not shown an interest in buying the product.
Eskom denies that the utility is wasteful in terms of bearing consumption at the Arnot power station.
“There are 72 seal-air fan bearings in service at Arnot power station. During the last year, the station only had three failures. The bearing replacement cost was R23 000 and the replacement time was about three hours for each incident. These failures had no impact on production, as the spare mill was put in service,” the utility states.
Meanwhile, Steinhobel says Sekela Bearings also offers a type of bearing, which was used in the Grootvlei power station, in Mpumalanga, before it was mothballed in 1989/90
The six units at the Grootvlei power station were mothballed between 1989 and 1990, owing to surplus electricity generation capacity in South Africa; however, its six 200 MW units were demothballed by the end of 2011 as part of Eskom’s return-to-service projects.
“When Eskom closed the Grootvlei power station, it sold off all the spares. I have managed to get my hands on some of the bearing spares.”
Steinhobel claims that one of the spares was specially made for the Grootvlei power station and is not manufactured anywhere else in the world. It is used in the Rothemühle air heater of the power station.
“We believe that the bearings currently in service at Grootvlei have been patched and are damaged.”
Eskom also denies this claim, saying that, while the utility may sometimes switch parts between power stations to save costs, it ensures that all power station components are well maintained.
In January 2011, Eskom launched its quarterly State of the Power System briefings, in line with its commitment to keep stakeholders informed about the state of South Africa’s power system
Public Enterprises Minister Malusi Gigaba said, in February, that the utility had a highly developed maintenance policy designed to ensure that areas at risk are dealt with in order of priority through a consistent schedule of maintenance and inspection work across its fleet of power stations.
Edited by: Chanel de Bruyn© Reuse this Comment Guidelines
Other Eskom News
The Eskom Holdings’ Board of Directors took a decision in 2004 to return three power stations, Camden, Grootvlei, and Komati, which had been mothballed in the late 1980s and early 1990s, due to the declining reserve margin and the prohibition on constructing new...
Updated 7 hours ago As industry prepares for the launch of South Africa’s digital terrestrial migration, the South African Communications Forum (SACF) hosted a workshop to determine the country’s readiness in terms of compliance of set-top boxes [STBs] and access to funding. The...
Updated 7 hours ago Higher Education and Training Minister Blade Nzimande has outlined plans for the development of a new health and allied sciences university into which the Medical University of Southern Africa (Medunsa) campus of the University of Limpopo, located in Ga-Rankuwa, will...
Updated 7 hours ago The costs of communicating have to drop, Communications Minister Yunus Carrim said on Wednesday. "Clearly, the costs have to come down. It's not just in the interests of the poor and disadvantaged but the economy as a whole," Carrim said in a statement following a...
Recent Research Reports
Steel 2014: A review of South Africa's steel sector (PDF Report)
Creamer Media’s Steel 2014 report provides an overview of the global steel industry and particularly of South Africa’s steel sector over the past year, including details of production and consumption, as well as the country's primary carbon steel and stainless...
Projects in Progress 2014 - First Edition (PDF Report)
This publication contains insight into progress at the delayed Medupi and Kusile coal-fired projects, in Mpumalanga and Limpopo respectively, as well as at the Ingula pumped-storage scheme, which is under construction on the border between the Free State and...
Automotive 2014: A review of South Africa's automotive sector (PDF Report)
The report provides insight into the business environment, the key participants in the sector, local construction demand, geographic diversification, competition within the sector, corporate activity, skills, safety, environmental considerations and the challenges...
Construction 2014: A review of South Africa's construction sector (PDF Report)
Construction data released during 2013 hints at a halt to the decline in the industry during the last few years, with some commentators averring that the industry could be poised for recovery. However, others have urged caution, noting that the prospects for a...
Electricity 2014: A Review of South Africa's Electricity Sector (PDF Report)
This report provides an overview of the state of electricity generation and transmission in South Africa and examines electricity planning, investment in generation capacity, electricity tariffs, the role of independent power producers and demand-focused initiatives,...
Defence 2013: A review of South Africa's defence industry (PDF Report)
Creamer Media’s 2013 Defence Report examines South Africa’s defence industry, with particular focus on the key players in the sector, the innovations that have come out of the defence sector, local and export demand, South Africa’s controversial...
This Week's Magazine
The Electronic Systems Laboratory (ESL) of the Department of Electrical and Electronic Engineering at Stellenbosch University is strongly reaffirming its position as one of South Africa’s leading centres for satellite technology and expertise. It is currently...
The world’s lowest-cost diesel-electric locomotive is not made in China, but in Pretoria, at RRL Grindrod Locomotives’ newly upgraded 30 000 m2 plant. The company’s locomotive pricing is “more competitive than any other original-equipment manufacturer (OEM)...
The South African Defence Review 2012, released to the public at the end of last month (despite the year given in its title) recommends the creation of the post of Chief Defence Scientist. This official would be responsible for the management of defence technology...
AltX-listed engineering technology company Ansys has been awarded an R188-million contract by Transnet to supply integrated dashboard display systems to the freight rail utility’s locomotives. Black-owned and controlled Ansys developed the bespoke integrated system...
South Africa’s sole nuclear power station Koeberg, which is located in the Western Cape, breached a major operations milestone on April 4, which marked the thirtieth anniversary of Unit 1 having been connected to the grid. Eskom, which operates the two-unit plant,...