Wafer Type Centerline Butterfly Valve
1. Product Overview
Metals Valve’s wafer type centerline butterfly valves are used in on-off block applications, with a simple disk in line with the center of the valve body. Generally, wafer type centerline butterfly valves are made from cast iron or another inexpensive metal and are lined with rubber or a polymer. The wafer body, sometimes called the flangeless body, is a flat body that has a minimal face-to-face, which is equal to twice the required wall thickness plus the width of the packing box. Within the flow portion of the body. Wafer type centerline butterfly valves are more commonly applied in the smaller sizes, 12 in and less.
2. Design Standards and Design Features
Design Standards
Design/Inspection standards: API 609, ANSI 125/150, BS4504.
Design Features
(1) ISO 5211 mounting flange accomodates direct mounting of all types of actuators, including: handles, gear operators, electric and pneumatic.
(2) O-Ring seals keep dust and moisture from entering the upper stem journal.
(3) Tertiary stem seal provides further assurance against stem leakage.
(4) Stub shaft design allows the disc to float within the flowwat increasing cycle life.
(5) Stem bushings reduce torque and isolate the stem from the valve body, preventing seizure of the stem due to corrosion in the stem journal.
(6) Smooth finished disc flats mate with seat flats to give a highly efficient primary seal which prevents leakage into the shaft area and minimizes torque
(7) Precision profile provides bubble-tight shut-off, assures minimum torque and longer seat life. Maximum flow is achieved by eliminating the “through shaft” and external disc fasteners.
(8) Seat to flange seal eliminates the need for flange gaskets.
(9) Phenolic backed seat is non-collapsible, stretch-resistant, blow-out proof and easily replaced in the field.
3. G.A Drawing & Material Selection for Wafer Type Centerline Butterfly Valve(with pin)
G.A Drawing
Material Selection
No. | Part Name | Materials |
---|---|---|
1 | Body | Cast Iron Standard ASTM A126 Grade B, DIN 1691 GG25 |
2 | Disc | Ductile Cast Iron Standard ASTM A536, DIN 1693 GGG40 |
3 | Seat | Buna-N or EPDM |
4 | Shaft | Stainless Steel Standard ASTM 316 410 416 |
5 | Pin | Stainless Steel Standard ASTM 316 410 416 |
6 | Key | Carbon Steel |
7 | "O" Ring | Buna-N or EPDM |
8 | Bushing | PTFE |
4. G.A Drawing & Material Selection for Wafer Type Centerline Butterfly Valve(without pin)
G.A Drawing
Material Selection
No. | Part Name | Materials |
---|---|---|
1 | Body | Cast Iron Standard ASTM A126 Grade B, DIN 1691 GG25 |
2 | Disc | Ductile Cast Iron Standard ASTM A536, DIN 1693 GGG40 |
3 | Seat | Buna-N or EPDM |
4 | Shaft | Stainless Steel Standard ASTM 316 410 416 |
5 | Pin | Stainless Steel Standard ASTM 316 410 416 |
6 | Key | Carbon Steel |
7 | "O" Ring | Buna-N or EPDM |
8 | Bushing | PTFE |