What is a lug check valve?
The Keckley retainerless wafer lug body double disc check valve features a single cast body without pin retainer holes in the body. This design minimizes prospective leak paths through the valve body making it a preferable option for highly toxic, corrosive, or hazardous gas chemical processing applications.
What is the difference between lug and wafer?
The difference between a Wafer and Lug type Butterfly valve is only the mounting scheme [1] and [2]. Wafer type valves don’t have attachment lugs, though them may have alignment lugs. They are sandwiched between the flanges on the ends two lengths of pipe.
What is a lugged wafer valve?
Lug-style butterfly valves are usually composed of metal such as ductile iron or steel. They feature threaded tapped lugs positioned on the valve flanges for bolt connections. Lug-style butterfly valves are suitable for end-of-line service but a blind flange is always recommended.
What is a Retainerless Wafer check valve?
In many check valves, there are four holes in the body of the valve that are used to mount the hinge pin and stop pin. A retainerless design does not have any holes passing all the way through the body of the valve.
What does a wafer valve do?
The wafer style butterfly valve is designed to maintain a seal against bi-directional pressure differential to prevent any backflow in systems designed for unidirectional flow.
What is wafer connection?
In a wafer connection the valve is installed between the pipe flanges and tightened to its place with the bolts for the pipe flanges. Wafer type body is the lightest body version for mounting between piping flanges. Therefore a wafer valve use to be cheaper than other valves. Also it is fast mounting.
What is Retainerless design for check valve?
The Retainerless type is a type which body without pin retainer holes in the body. Retainerless type check valve use carrier and screw instead of retainer function to fix the pin. Retainerless check valve design also provides higher integrity on high pressure, ensuring no concerns about leakage.
What is api594?
API Std 594, Check Valves: Flanged, Lug, Wafer, and Butt-welding, is a standard developed and published by the American Petroleum Institute (API) that covers the design, materials, face-to-face dimensions, pressure-temperature ratings, and examination, inspection, and testing requirements for Type “A” and Type “B” …
What is the difference between wafer check valve and swing check valve?
Wafer check valves get their name from their wafer thin design. Swing check valves, as the name implies, also uses a swinging disc to allow or block flow. The difference between the two is in the body design. Swing check valves are not designed for extremely tight spaces like the wafer check.
How does a wafer style check valve work?
Wafer check valves work much in the same way as swing check valves. If and when flow reverses direction through the valve, the flow of material pushes the disc back into the seating arrangement, thus closing the valve off from the flow of material. Wafer check valves are designed to be slim and unlikely to clog.