Industrial Valve Glossary

A valve with three ports that directs flow from one inlet to one of two outlets (or vice versa). Used in duplex filter and cooler circuits to switch service between two equipment trains without interrupting flow.

A valve with six ports that simultaneously switches both the inlet and outlet of a duplex system in a single operation. Available in Same-Side, Inline, and Opposite-Side port configurations.

A pressure-temperature rating class per ASME B16.5. For carbon steel at 100°F, Class 150 is rated to approximately 285 PSI. The most common flange rating for lube oil and cooling water service.

A higher pressure-temperature rating class per ASME B16.5. For carbon steel at 100°F, Class 300 is rated to approximately 740 PSI. Used for higher-pressure lube oil and hydraulic applications.

American Petroleum Institute Standard 598 — "Valve Inspection and Testing." Defines pressure test requirements for industrial valves. HYCOA JR-33 transfer valves meet API 598 shell and seat test requirements.

American Petroleum Institute Standard 614 — "Lubrication, Shaft-Sealing, and Oil-Control Systems and Auxiliaries for Petroleum, Chemical, and Gas Industry Services." Specifies requirements for lube oil and seal oil systems, including transfer valve zero-leakage performance.

American Society of Mechanical Engineers. HYCOA transfer valves are designed and rated in accordance with ASME B16.5 flange standards for Class 150 and Class 300 pressure-temperature ratings.

The standard end-connection style for HYCOA transfer valves, using bolted flanged bonnets. Available in ANSI Class 150 and Class 300 ratings. The bonnet houses the shoe seal stack assembly.

A synthetic rubber elastomer (also called NBR or Nitrile) used for shoe seals and soft parts kits. Rated for service from -20°F to 250°F. The standard elastomer choice for most lube oil and fuel oil applications.

An end-connection style where the valve body is welded directly into the pipeline. Available as an option on HYCOA transfer valves for applications where flanged connections are not preferred.

Standard body material for HYCOA transfer valves (model prefix J3C… or J6C…). Suitable for most lube oil, fuel oil, and water service applications. ASTM A216 WCB casting or ASTM A105 forging.

A heat exchanger system with two parallel cooler units and a transfer valve, allowing one cooler to be isolated for cleaning or repair while the other remains in service.

A filtration system with two parallel filter housings and a transfer valve that allows one housing to remain in service while the other is cleaned or serviced — without interrupting flow or shutting down the system.

Electro-Hydraulic Control system — uses phosphate ester hydraulic fluid to control turbine steam admission valves. Requires Viton-sealed transfer valves due to the aggressive nature of phosphate ester fluid.

A 6-way transfer valve configuration where the inlet and outlet ports are located on opposite ends of the valve body, allowing straight-through pipe-run installation. The "Problem Solver" for retrofitting old problem valves.

A lubrication system that supplies filtered, cooled oil to rotating equipment bearings and seals. Transfer valves are used in duplex filter and cooler circuits to allow on-line maintenance without equipment shutdown.

The ability to service, clean, or replace a filter element, cooler bundle, or strainer basket while the system remains in continuous operation. Transfer valves enable on-line maintenance by isolating one equipment train while the other remains in service.

A 6-way transfer valve configuration where inlet and outlet ports are on opposite sides of the valve body. A special-order configuration for specific piping layouts where same-side or inline porting cannot be used.

A 6-way transfer valve configuration where both the inlet and outlet ports are located on the same side of the valve body. The most common 6-way configuration; simplifies piping layout.

A pressurized oil system that prevents process gas from escaping along compressor shaft seals. Transfer valves in seal oil systems must provide zero internal leakage to maintain seal integrity.

HYCOA's patented resilient sealing element — a metal-backed elastomeric shoe that provides zero internal leakage. The shoe retracts during valve rotation (eliminating frictional drag) and seats firmly in the closed position. Available in Buna-N and Viton elastomers.

A complete set of elastomeric seals and wear components required for a full valve rebuild. Includes bonnet seals, lip seals, seal retainers, and roll pins. Available for Bolted Bonnet and Victaulic end connections in Buna or Viton.

A specialized installation tool required for proper seating of replacement shoe assemblies in HYCOA transfer valves. A separate tool is required for each valve size (1½″–2″, 3″, 4″, and 6″).

Optional body material for HYCOA transfer valves (model prefix J3S… or J6S…). Used for corrosive service, high-purity applications, or where carbon steel is not acceptable. Typically 316L SS.

A dual-body transfer valve that simultaneously switches two independent circuits in a single handle operation. Used when two separate fluid systems must be transferred at exactly the same moment.

A grooved mechanical pipe coupling system. HYCOA transfer valves are available with Victaulic-style grooved end connections as an alternative to flanged connections. Not available for 8″ valves.

A fluoroelastomer (FKM) used for shoe seals and soft parts kits in high-temperature or chemically aggressive service. Rated from -20°F to 350°F. Recommended for EHC hydraulic fluid, phosphate ester fluids, and elevated-temperature lube oil.

During valve changeover, the HYCOA shoe seal retracts away from the valve body before rotation begins, eliminating metal-to-elastomer friction. This allows smooth, low-effort operation even under full system pressure.

A performance characteristic of HYCOA transfer valves — the patented shoe seal provides a positive shut-off with no internal bypass leakage between the active and standby circuits. Critical for API 614 compliance.