Emerald Group Publishing Limited
Copyright © 2011, Emerald Group Publishing Limited
Victrex plc international expansion
Article Type: Industrial news From: Anti-Corrosion Methods and Materials, Volume 58, Issue 5
As part of the company’s continual drive to provide better service to customers in Japan, Victrex Polymer Solutions (VPS), a division of Victrex plc, has announced it is to build a second technical centre in Asia – the Victrex Japan Technical Center in Japan. The new facility will allow VPS to provide a higher level of technical service, with improved responsiveness to its customers. The new centre will enable VPS to work alongside customers when they need to develop new applications.
The three Victrex technical centres in Japan, China and the UK will provide comprehensive technical support for the entire Victrex customer base. Each centre will have common characterisation, analysis and processing capabilities, complemented by specialist technical competencies and capabilities that reflect local customer and market needs. The technical centres will be able to work closely with customers to help develop and design unique, value-added solutions.
China Wuxi Shuangling Electrical-apparatus Factory, a leading Chinese automotive parts maker, has selected VICTREX® PEEK™ polymer for the manufacture of the vanes in the company’s rotary vane vacuum pump. This vacuum pump is used in both diesel and turbocharged direct-injection gasoline engines at some of China’s top automotive makers, including Great Wall Motors, Jiangling Motors, SAIC Motor, and Hawtai Motor.
The vacuum pumps provide braking assistance, by means of a brake booster, and provide support for supercharging and exhaust gas recirculation. Vacuum pumps contribute to the overall safety and efficiency of the braking system by supplying brake boosters with negative pressure (0,9 bar), to reduce the amount of pedal effort required for braking. Therefore, vacuum pump reliability, throughout a car’s life time, is a critical design requirement.
Any failure or deterioration in the performance of the vacuum pump would have an adverse effect on the braking performance of an automobile and may even lead to accidents. Therefore, auto makers have established stringent requirements for the reliability and performance of vacuum pumps prior to assembly.
Specific vane and material requirements
In order to keep vanes working efficiently over a specified lifetime under their environmental and operating conditions they require:
High resistance to wear at the tip.
Low COF, particularly for electrical pumps.
Tight dimensional tolerances.
A thermal expansion similar to or slightly greater than that of aluminium.
High strength/weight ratio.
Driven by pedestrian safety legislation, the pumps have had to be positioned closer to the oil sump, where they experience increased service temperatures, up from 100-110°C to 120-130°C.
Working alongside VPS, Wuxi Shuangling aims to provide customers with higher performance components that can meet the demands of harsh automotive operating environments, with performance superior to that of traditional materials, such as polyphenylene sulfide (PPS) and graphite.
Selection of materials is critical to the performance and operating reliability of vacuum pumps. VICTREX PEEK polymer has excellent resistance to all automotive fluids – in this specific case engine oil – and has demonstrated very good compressive creep resistance at elevated temperatures. It is a material proven over decades of experience. It is a unique material, able to maintain high mechanical strength at 150°C for over 5.000 h, and it resists becoming brittle when stressed by mechanical and frictional loads. It withstands the forces generated during cold starting (−40°C) where the engine oil has a relatively high viscosity. The excellent wear resistance results in a longer service life.
Li Huicheng, deputy general manager of Wuxi Shuangling said, “We believe that by using proven VICTREX PEEK polymer we will be able to offer customers a top-quality vacuum pump and an innovative solution to enhance their competitiveness. The low density of the Victrex wear grades helps us to even reduce CO2 emissions because the moment of inertia of the component is reduced, compared to other materials such as PPS. This helps our customers meet their target of reduced CO2 emissions.”
Wear resistance is becoming a more important factor for vane type pumps. Owing to increasing speeds and temperatures, the load on materials has increased steadily, even for lubricated mechanical pumps. “If we consider a doubling of the engine speed from diesel to gasoline engines, the centrifugal forces are proportional to pressure and increase by a factor of four, meaning that pv (pressure/velocity) values increase 8 times,” noted Eastward Yu, Senior Market Development Manager, at VPS, China.
In recent years, the automotive industry has faced increasing pressure to maximize performance and safety while minimizing fuel consumption, weight and cost. As a result, high durability, low cost, driving comfort, and low environmental pollution have become the core measurements of R&D efforts. Victrex’s materials and deep technical support are helping automotive part makers around the world boost product performance, improve design flexibility, and extend service part life while successfully meeting the industry’s demanding material requirements.
More information is available from: www.victrex.com