A gate valve is a valve that opens by lifting a gate from the path of the fluid. Gate valves are generally used in larger pipe sizes from 2½” - 12” and can be offered on either bronze or coated ductile iron. Gate valves also have a variety of stem arrangements including NRS (Non-Rising Stem) and OS&Y (Outside Stem and Yoke).
Examples of gate valves include bronze gate valves [Model 48OSYBR] iron gate valves, NRS and iron gate valves, resilient seated [Model 48] and iron gate valves, OS&Y [Model 48OSY].
A vacum breaker is a device designed solely to protet against backsiphonage on a plumbing system. Vacum breakers can not prevent against backpressure, and are generally not testable devices. A backflow preventer is a device designed to prevent against both backsiphonage and backpressure.
Examples of vacum breakers include pipe applied atmospheric type vacum breakers [Model 35XL] hose-connection vacuum breakers [Model BFP-9] [Model BFP-8F] pressure vacuum breakers [Model 720A] [Model 420XL] laboratory faucet vacum breakers [Model 35XLVCH] [Model 730] and spill-resistant vacum breakers [Model 460].
Dual checks are not testable in line whereas double check and reduced pressure principle devices are. Dual checks and double checks prevent against low hazard threats (water discoloration, smell and taste), whereas reduced pressure principle devices protect against these as well as high hazard threats (dissolved chemicals in the water that can cause illness and/or death).
Examples of dual check backflow preventers are [Model 700XL] [Model 705] [Model 700FP]. Examples of dual check backflow preventers designed specifically for beverage dispensing equipment are [Model 700XL] [Model 705].
Examples of dual check backflow preventers are [Model 350A] [Model 350AST] [Model 350XL 450] [Model 950XLT2] [Model 350].
Examples of reduced pressure principle backflow preventers are [Model 375A] [Model 375XL] [Model 375ST] [Model 375AST] [Model 375].
What is a detector assembly on a double check or reduced pressure principle device?
Plumbing systems that are by code not connected to a water meter (such as fire hydrants) have no way of determining whether water is being consumed downstream of the device via either component malfunction or water theft. A detector assembly is a bypass system with its own inline meter, designed to detect low flow rates through a normally un-metered plumbing line that requires a backflow device.
Examples of double check, detector assembly backflow preventers are [Model 350ADA] [Model 350ASTDA] [Model 950XLTDABF] [Model 350DA] [Model 450DA].
Examples of reduced pressure detector, fire-protection, backflow preventer assemblies are [Model 375ADA] [Model 375ASTDA] [Model 475DA] [Model 375DA].
A water regulator is a direct acting device. This means that the entire flow through the plumbing system is directed through the valve itself. A regulator contains a spring that biases the valve open, based on a set pressure range. Once the downstream pressure in the plumbing system is exceeded the spring compresses and the valve inside the regulator begins to close. A water control valve is a diaphragm valve with a pilot assembly that is plumbed outside of the main body of the valve. The actions of this pilot assembly control the operation of the main valve. In the case of a pressure regulating water control valve, the pilot assembly would contain a water regulator thereby regulating water pressure in the main valve. Water regulators tend to be for pipe sizes from ½” to 3”, whereas water control valves tend to be in pipe sizes from 1¼” through 10” and larger as required.
Examples of water regulators are [Model NR3XL] [Model 500XLTYSBR] [Model 600XL] [Model 70XL].
Examples of water control valves are [Model ZW209] [Model ZW206] [Model ZW205]