What is API 609 Standard?

This standard covers design, materials, face-to-face dimensions, pressure-temperature ratings, and examination, inspection, and test requirements for gray iron, ductile iron, bronze, steel, nickel-based alloy, or special alloy butterfly valves.

The following two categories of butterfly valves are included:

Category A—Manufacturer’s rated cold working pressure (CWP) butterfly valves, usually with a concentric disc and seat configuration. Sizes covered are NPS 2 to NPS 60 for valves having ASME Class 125 or Class 150 flange bolting patterns.

Category B—ASME class and pressure-temperature-rated butterfly valves that have an offset seat and either an eccentric or a concentric disc configuration. Sizes covered are listed below:
for lug and wafer, Class 150 and 300: NPS 2 to NPS 60;
for lug and wafer, Class 600: NPS 3 to NPS 60;
for double-flanged short and long pattern, Class 150, 300, and 600: NPS 3 to NPS 60;
for butt-welding ends, Class 150, 300 and 600: NPS 3 to 60;

What is an API 609 Butterfly Valve?

The API 609 butterfly valve is used to shut off or modulate the flow of a fluid (isolation and regulation). API 609 Centric butterfly valves (soft seated) are preferred to gate and ball valves for low-pressure and non-critical applications as they are cheaper, lighter, and easier to install. Eccentric butterfly valves (double offset and triple offset valves) with metal seats have surged in popularity and compete with globe and ball valves for some applications.

GET API 609 BUTTERFLY VALVE PRICE

API 609 Butterfly Valve Working Principle

The key component of a butterfly valve is the disc, a metal ring that is positioned at the centerline of the pipe and connected to an external actuator (manual level or actuator) via a rod.

Compared to a ball valve, the disc of a butterfly valve is always in contact with the fluid conveyed by the pipeline and creates, therefore, a pressure drop.

In the closed position, the disc blocks the bore of the valve, and, in an open position, the disc allows the passage of the fluid.

A quarter turn movement is needed to switch the valve from a fully open to a fully closed position (and such movement can be executed as quickly as for ball valves).

Specifications of API 609 Butterfly Valve

Face to Face Dimensions: ANSI B16.10

Flange end Dimension: ANSI B16.5

Butt Welded Dimensions: ANSI B16.25

Design and Manufacture: API 609

Pressure Test: API598

Materials：WCB 、WC6 、WC9 、CF8、 CF8M、 CF3、 CF3M 、CN7M、LC1

LC2、LC3、LCB、LCC、Monel、20# Alloys、4A、5A、C95800、C95500, etc.