TPi March 2013

products & developments Seals for valves

When

operating

Gesellschaft für Dichtungstechnik mbH (GFD) manufactures products for the valve industry, such as special seals for valves used onshore and offshore. GFD seals are used in ball valves, butterfly valves, actuators, and control or gate valves. For these applications, the company can produce sizes from 2 to 3,000mm diameter in various designs.

conditions require a special solution, GFD seals come into operation, for example low temperatures from -196°C or -270°C which can occur in liquid helium, or in particularly high temperatures up to +980°C. aggressive media, hot gases and pressures of several hundred bar, GFD has developed appropriate seal solutions. For

Metal sealing rings

universal chemical resistance as well as defined low friction and sealing force. GFD seals are also designed for applications other than valves: for laser systems, seals for aerospace industry, for gas turbines, autoclaves in biotechnology and chemical industry, medical and laboratory equipment, and sterilisable designs for the pharmaceutical and food industries. Gesellschaft für Dichtungstechnik mbH – Germany info@gfd-dichtungen.de www.seals.de specially developed as a master batch for use in polymeric and coating applications. The products are RoHS- and REACH-compliant, and FIFRA exempted. They deter the pests by making use of the sensory mechanisms. They do not interfere with the properties of the polymer and are completely inert within the polymer matrix, apart from acting as an aversive. Rodrepel and Termirepel do not volatilise and are compatible with all kinds of polymers. They have undergone extensive testing at testing institutes like the BAM Institute in Germany and the Haffkine Institute in India.

The company’s spring-energised seals are made from high quality PTFE compounds, with an internal stainless steel spring providing at the sealing lip permanent elasticity and balances as cold flow and abrasive wear. The GFD seals are used in the housing or in the disc of butterfly valves. The spring-energised PTFE-seals can be used at pressure up to 2,500 bar, at temperatures from -250°C to +316°C with slow, ‘stick-slip-free’ movement, and at high speed. They also offer and wiring harness of automobiles by rodents can cause thousands of dollars in losses. Conventional methods of rodent and termite control fall short, as they do not effectively control the pests. Also, being toxic they cannot safely be used in all applications. It is imperative to effectively solve the problem of polymer piping damage by pests and also to provide a long- term solution. With this aim, and keeping in mind environmental as well as safety aspects, Rodrepel ® ™ and Termirepel ® ™ were developed by C Tech Corporation. Rodrepel and Termirepel are patented non-toxic, non-hazardous and environmentally friendly aversives

Spring-energised PTFE-seals

Polymers and pests Polymers and plastics are widely used and form the base of a host of materials. As large as their use is, even larger is the threat they face from rodents and pests. Rodents are attracted by the sweet smell of polymers and consequently rodent damage is one of the most widespread complaints from the pipe industry.

Gas pipelines, drip irrigation pipelines, and tubing for wires and cables are some of the most-affected by pests. Damage to gas pipelines can have adverse consequences. Damage to drip irrigation pipelines by rodents and subterranean termites not only defeats the purpose of water conservation but it is also expensive to replace the pipe. Damage to the tubing

C Tech Corporation – India dianna@ctechcorporation.com www.ctechcorporation.com

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Tube Products International March 2013

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