OPUS

Valve Backflow Preventer

Image provided by Apollo Valves

Backflow preventers protect against reversed flow caused by backpressure or backsiphonage. Backsiphonage occurs when the supply pressure drops below atmospheric pressure, thus creating a vacuum. Backpressure occurs when the supply pressure drops below the residual pressure in the downstream piping. Either of these conditions can result in backflow. When cross-connections or potential cross-connections exist, backflow can result in pollution or contamination of the potable water supply.

A double-check valve assembly may be used under continuous pressure and protect against both backsiphonage and back-pressure conditions. It consists of two single check valves coupled within one body and furnished with test cocks and two tightly-closing gate valves.

Double-check valves have a test capability feature that gives this device a big advantage over the use of two independent check valves. Double-check valves can be readily tested to determine that both valves are functioning properly and are not fouled by debris. Each check valve is spring-loaded closed, and requires approximately 1 psig of pressure to open. Spring loading provides the ability to "bite" through small debris and still maintain the seal. Spring loading is a protection feature not prevalent in unloaded swing check valves.

Double checks are commonly used to protect against low-to-medium hazard installations, such as in food-processing steam kettles and in apartment projects.



Manufactures and Suppliers Participating in OPUS

ANVIL International

Anvil International offers a full line of domestically-produced iron fittings, steel nipples,...
(click for details)

Apollo Valves

Apollo Valves has been a global leader in valve innovation for over 75 years, providing valves...
(click for details)

Aquatherm

Aquatherm is dedicated to providing the very best piping systems for anyone, from engineers to...
(click for details)

Embassy Group LTD

Embassy Group LTD is a 100-percent member owned, 3.2 billion dollar corporation consisting of...
(click for details)

F.W. Webb Company

F.W. Webb Company is a multi-faceted distributor of plumbing and heating, HVAC and controls,...
(click for details)

Ferguson

Ferguson specializes in providing PVF, Plumbing, HVAC and Related Specialty Products and...
(click for details)

Grinnell Mechanical Products, A Tyco International Company

Grinnell Mechanical Products, a leading brand of Tyco International Company, manufactures a wide...
(click for details)

J.O. Galloup Company

J.O. Galloup Company is a premier distributor of commercial and industrial piping products,...
(click for details)

Johnson Controls, Inc.

Johnson Controls, Inc. manufactures, installs, integrates, services and operates systems that...
(click for details)

MIFAB, Inc.

MIFAB is a manufacturer of seven different commercial plumbing product groups: 1) specification...
(click for details)

NIBCO INC.

NIBCO Inc. is a recognized industry leader of flow control solutions to the residential and...
(click for details)

Watts Water Technologies

Watts Water Technologies  designs and manufactures valves and related fluid handling...
(click for details)

WinWholesale, Inc.

WinWholesale, Inc. is comprised of over 525 wholesale distribution locations. Along with Noland...
(click for details)

Zurn Industries, LLC

Zurn Industries markets and manufactures roof/floor drains, interceptors, cleanouts, water...
(click for details)