Claw pumps: enabling efficiency and durability

Jon Lawson

Offering a low maintenance solution for the creation of continuous vacuum or pressure, claw pumps from EuroVacuum Products present the ideal selection for a wide range of industrial applications. Equipped with variable speed drives, combined with innate design benefits for reliable operation, claw pumps adhere to the stringencies of even corrosive environments.

Claw pumps compress gas within the pump chamber via two irregularly shaped rotors or ‘claws’ that counter rotate inside the casing. To create internal compression, the pump outlet is sealed temporarily until adequate pressure is attained, with the contained gases then expelled via the pump outlet. An anti-suck back valve in the inlet flange prevents gas backflow into the chamber.

The rotors themselves are synchronised by gears, which are generally oil lubricated to ensure maximum service life. Pumping and gear chambers are separated using durable labyrinth seals. Air cooled, dry running and contactless in operation, claw pumps when treated correctly can run for years without requiring rebuild.

Reliability and durability are guaranteed through the design of the pump. Contactless operation ensures a lack of wear parts within the chamber, increasing the duration of maintenance intervals. With no oil lubricating the rotors within the casing, servicing is kept to a minimum, with the risk of lubricant related contaminants entering the chamber eliminated - which can damage the rotors and consequently the efficiency of the pump. Furthermore, the rotation of the claws offers great benefits. The shape of the rotors serves to remove deposited particles that may enter the pump, which makes claw pumps an ideal selection for applications in potentially corrosive environments. This again protects the casing and rotors from becoming damaged due to contamination. To further compound these properties, EuroVacuum Products claw pumps feature Teflon coating on the rotors and compression chamber to further protect against corrosion.

The inclusion of variable speed drives (VSDs) enhances the performance of the pumps also. Energy efficiency is greatly increased during operation, especially during start up, with the VSDs minimizing the stress on the pump during potentially hard wearing processes. As the name suggests, the VSDs also offer unparalleled control for applications that require various speed requirements. In the long term, this can reduce energy costs for end users. The direct drive design also eliminates any concerns regarding belts – which can experience wear and require replacement.

Claw pumps require minimal space due to their compact design and are easy to install; saving time during installation and conserving precious capacity on the production floor. These numerous benefits have seen claw pumps become a staple in a number of industries and processes, including packaging, CNC routing, pneumatic conveying, holding and lifting, wood works, pick and place, medical applications, plastic processes and central vacuum systems.

EuroVacuum Products utilises great experience in vacuum technology to specify, install and provide dependable service to aid end users to achieve vacuum efficiency across the range. With a selection of claw pumps varying in size from 60 to 500m3/h combined with support from certified engineers; EuroVacuum Products can ensure that all end users can fully utilise the benefits of efficient products that integrate seamlessly with multiple demands, applications and requirements.