When an Italian pump manufacturer recently tested self-lubricating, wear-resistant Vesconite Hilube line shaft bushings at the Best Efficiency Point (BEP) of a submersible pump, the objective was straightforward: establish how the material would perform during sustained operation at the pump’s most efficient operating point.
The pump ran continuously for 40 hours. After the test, the manufacturer reported that the Vesconite Hilube bushings showed no signs of scratching or wear. The company subsequently ordered the tested line shaft bushings, as well as additional Vesconite Hilube components for its pumps.
For Vesconite Bearings, the test represented the latest chapter in a pump story that began more than five decades ago in the demanding environment of South Africa’s deep-level gold mines.
Pump applications born in South Africa
In the 1960s and 1970s, pumps operating in the South African goldfields faced challenging conditions. Deep underground mines employing tens of thousands of miners needed high-capacity pumping systems to manage substantial volumes of water, while equipment reliability was critical to maintaining production.
One early application involved refurbishing an 825 kW, 11-stage centrifugal pump. The pump incorporated Vesconite wear components, including wear rings and packing rings.
The application was significant because it introduced engineering plastics as an alternative to conventional metallic pump components such as phosphor bronze. Vesconite’s combination of low friction, wear resistance, and self-lubricating properties offered advantages in these difficult pump environments.
The material could also reduce the risk of metal-to-metal seizure during periods of low flow or momentary dry running. In a deep-level mine, avoiding damage to impellers, casings and shafts meant an important difference to equipment availability and maintenance requirements.
From mine pumps to modern pump testing
Standard Vesconite and Vesconite Hilube pump parts have since been used in tens of thousands of pumps around the world, including 44 pump OEM manufacturers, which specify the components in their pumps, and 548 pump repair centres, which incorporate Vesconite components in repairs and refurbishments. The materials have been used in vertical turbine, vertical spindle, mixed-flow, multi-stage, submersible, split-case, centrifugal, diaphragm, gear and LPG pumps.
Vesconite Hilube has specifically been developed for demanding bearing applications involving water. The material is self-lubricating, has low water absorption and maintains its machined dimensions without swelling. It is also resistant to corrosion, oils and fuels and can provide dry-start capability for up to one minute.
These characteristics can be valuable in pump applications where conventional bearing materials may be affected by water absorption, corrosion or dimensional changes.
Efficiency begins with the whole pump
The recent Italian application demonstrates how the role of pump bearings is evolving alongside wider industry attention to efficiency.
The BEP is the operating point at which a pump achieves its maximum hydraulic efficiency. While a bearing material does not alter the hydraulic BEP itself, the condition of the shaft, bushing and impeller interfaces can influence how consistently a pump operates.
Excessive clearance can allow shaft movement, potentially contributing to vibration, misalignment and internal leakage. Vesconite Hilube can be machined to close clearances because of its dimensional stability in water.
By decreasing the clearance, one can reduce excessive shaft movement and vibrations. This can lead to more stable pump operation.
The Italian manufacturer subsequently ordering additional Vesconite Hilube components, suggesting that the material’s performance during their BEP testing provided sufficient confidence for further use.
A growing UK presence
For UK pump manufacturers, repair companies and engineering businesses, access to the material is becoming increasingly straightforward.
Vesconite Bearings keeps a range of stock shapes at its warehouse facility in Eastleigh, UK. This local stock enables UK customers to source Vesconite products without relying solely on international shipments from the company’s manufacturing operation in South Africa.
UK customers can contact Vesconite Bearings’ European representative, Conrad Penzhorn, on +31 303 200 200 to discuss requirements and order stock. A UK office is going to be opened in October.
The European presence forms part of Vesconite’s broader international supply network. The company manufactures its engineering bearing and wear materials in South Africa and supplies customers in more than 100 countries.
Five decades of pump experience
From an 825 kW mine pump in South Africa in the early 1980s to BEP testing on a modern submersible pump in Italy, Vesconite’s experience in pumping has developed across changing technologies, industries and geographical markets.
The fundamental requirements, however, remain familiar. Pump operators need components that resist wear, remain dimensionally stable in water, minimise friction and help equipment operate reliably.
For pump manufacturers and users in the UK and Europe, Vesconite’s combination of long-established application experience, specialised engineering materials and local UK stock provides an alternative to conventional metallic bearing and wear components.
As pump manufacturers continue to focus on efficiency, reliability and lifecycle performance, the experience gained from decades of demanding applications offers a useful starting point for evaluating what happens inside the pump, as well as what happens at the hydraulic level.
Find out more www.vesconite.com
