With approval granted for the use of both Leser API specification safety relief valves and TLV steam traps and related equipment on Sasol plants, Heaton Valves Africa reports in a media release that it is looking ahead with optimism.

Heaton Valves Africa also acquired the Velan agency in 2001.

Product manager Clinton Parsons says that Velan is one of the world’s leading manufacturers of industrial valves, supplying to the chemical, petrochemical, oil and gas, fossil and nuclear power, cogeneration, pulp and paper and cryogenic industries.

Velan, founded in 1950 by AK Velan, manufactures commodity valves such as API 600 gate, globe and check units. It is believed that Velan is one of the last large manufacturers to still truly manufacture commodity cast steel gate, globe, and check valves in North America and Europe. However, with this in mind, Velan has a realistic outlook for the future, and has established a state-of-the-art production facility in Korea. Parsons says the motivation for this move was not driven by short-term profits, but by the desire to maintain the company’s position as one of the world’s largest manufacturers of API 600 valves.

As quality remains a top priority, the company employs a full-time metallurgist who visits the supply foundries to conduct quality assurance audits.

Product quality enhancement is made possible by assisting the foundries in updating foundry technology and methods. “Many people fail to realise the vital role played by valves in pro-cess facilities, partly due to their small representation of the total investment, but an incorrect valve selection or poor quality alternative can lead to major problems during construction and in ser- vice,” Parsons says. All standard Velan steel valves manufactured at any of its facilities are guaranteed to fall within maximum emission levels of 20 ppm for gasket and 100 ppm for stem seal.

This guarantee, based on extensive laboratory testing and field experience, is applicable to all the company’s steel valves under normal operating conditions, provided gland and body-bonnet bolting is torqued to the minimum values shown in the standard Velan maintenance tables, and with clean stems.

In order to maintain these levels, the company has performed numerous tests on alternative gasket types and supplies all API 600 specification valves with corrugated steel gaskets complete with graphite-filled channels as standard. “This format requires no retor-quing after long cycling and is effective under wide temperature and pressure fluctuations.

“These gaskets are also insensitive to flange finish, while the steel walls of the graphite channels provide additional protection against corrosion, oxidation and blow-out,” Parsons adds.

Velan API 600 gate valves feature a flexible round wedge, pioneered by the company originally, as standard, a design suitable for universal use for temperatures up to 538 ˚C, while the built-in flexibility compensates for seat face distortion. This flexibility also compensates for pipe stresses causing body deformation, a common problem caused by insufficient pipe supports in petrochemical plants. Velan API 600 swing-check valves have also benefited from the company’s expertise. Parsons says cage unit design with no body penetration ensures no leakage past the common gasketed hinge pin arrangement found on many competitors’ equivalents. This also eliminates the possibility of pin ejection. In order to facilitate routine maintenance without requiring complete valve removal from the process line, all internal components are accessible through the top cover. As with Velan API gate valves, all Velan swing-check valves feature stellite six hard-faced welded-in seats as standard. To eliminate the possibility of localised wear, discs are free to rotate from their disc hangers, another Velan innovation.