Compact valves for corrosive and ultra-pure liquids in PVC, PTFE, Kynar® & Polypropylene • ¼" through 1½" sizes
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Features
- Compact size with PTFE diaphragm construction.
- No metal in contact with liquid.
- Various end connections available.
- Million cycle non-sticking design.
- Various body materials available:
Geon® PVC, Corzan® CPVC, PTFE, Kynar® PVDF, Natural unpigmented Polypropylene.- Normally closed design
("fail-safe" spring to close; air to open).- Patented Fail-Dry® vented design.
- Inlet pressures to 100 PSI ---
(see table below for complete specifications.)Click here for a brief video demonstrating how Series BSDA works.
Designed for pressure and drain applications processing ultra pure water and highly corrosive chemicals. The valve is ideal for a wide range of uses, from pharmaceutical to semiconductor in PTFE, Kynar PVDF or Polypro body materials; car washes to chemical plants in the lower-cost Geon PVC body materials, and higher temperatures in those applications with Corzan CPVC bodies.
For high purity applications such as deionized water, Series BSDA provides the ultimate in non-leaching, contamination-free sealing. The standard valves are air pressure to open, with "fail safe" spring return to close. Because the diaphragm is attached to the piston, no inlet pressure is required to assist with opening. The BSDA is not designed for vacuum service.
Discontinued Series BSD was an earlier design with a non-attached diaphragm. Series BSDA and former Series BSD are identical in all other respects. Series BSDA supersedes Series BSD.
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Diaphragm Design
The standard diaphragm material is PTFE for the ultimate in purity, backed with FKM for the ultimate in strength and flexibility. The FKM side is not in contact with liquid.
Materials of Construction
Wetted body materials available standard are Geon® PVC, Corzan® CPVC, PTFE, Kynar® PVDF, and Natural Unpigmented Polypropylene. Other body materials and custom materials may be available, depending on costs and/or quantity.
Compact air cylinder head standard material is Geon PVC, regardless of the body material. Seals used for cylinder are Buna-N. Spring is steel; fasteners are stainless steel. None of these materials contact liquid. If for some reason these are not acceptable for your application, other air section materials can be provided depending on costs and/or quantity. We urge you to contact our Technical Group at (973) 256-3000 to discuss your application.
Operation
A 3-way air solenoid valve connected to the 1/8" NPT port on the air cylinder head is required to actuate the diaphragm valve. When air pressure (40 to 100 psi) is applied, the diaphragm valve opens. Consult the table below for complete air specifications. When the air pressure is vented away through the 3-way air solenoid valve, the internal spring automatically closes the diaphragm. (This is referred to as "normally-closed, air-to-open/spring return valve). The spring is not in contact with liquid. It is recommended that filtered, lubricated compressed air be used.
The cylinder head features multiple seals, in addition to the main diaphragm seal in contact with the liquid. There is a vent located between two seals (above the main diaphragm, below the cylinder head u-cups) that will "weep" in the event of a primary seal failure. The valve will still function, under pressure, without metal contacting liquid. This is the patented Plast-O-Matic Fail-Dry®, which adds an additional layer of "protection" for your process.
Piping Connections
The standard valves are precision machined from the highest quality brand thermoplastic bar stock with female NPT connections. Spigot connections are also available. For orders of 25 or more valves, connections can be provided with male threads, sockets, unions, etc. Please consult our Technical Group for more information, (973)256-3000.Applications
Series BSDA PTFE diaphragm valves have been used successfully in Semiconductor fabs, pharmaceutical processing, deionized water, chemical processing, potable water treatment, chemical injection systems, battery filling, wastewater treatment, dialysis systems, and many other applications since it was introduced in 1984. This is a proven design for high purity processes, providing 1,000,000 cycles in normal use.
Dimensions
| SERIES BSDA DIMENSIONS | |||||
|---|---|---|---|---|---|
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SIZE | A IN. MM |
B IN. MM |
C IN. MM |
D IN. MM |
| ¼" | 2.0 50.8 | 2.23 56.6 | 0.470 11.9 | 1.73 43.8 | |
| ½" | 2.5 63.5 | 2.96 75.8 | 0.687 17.5 | 2.38 60.3 | |
| ¾" | 3.0 76.2 | 3.65 92.6 | 0.780 19.8 | 2.50 63.5 | |
| 1" | 3.5 88.9 | 5.12 130.0 | 1.187 30.0 | 3.56 90.8 | |
| 1-½" | 5.0 127.0 | 6.00 203.2 | 1.750 44.8 | 6.44 138.1 | |
| Note: 1/8" & 3/8" sizes are also available on special order. Consult factory for details. | |||||
| BSDA MOUNTING HOLE DIMENSIONS |
||||
|---|---|---|---|---|
| Pipe Size |
E IN. MM |
F | ![]() |
|
| Thread Size |
Depth IN. MM |
|||
| ¼" | 1.625 41.3 | 8-32 | .625 15.9 | |
| ½" | 1.625 41.3 | 8-32 | .625 15.9 | |
| ¾" | 2.000 50.8 | ¼-20 | .750 19.1 | |
| 1" | 2.000 50.8 | ¼-20 | .750 19.1 | |
| 1-½" | 3.000 76.2 | ¼-20 | .750 19.1 | |
Specifications:
| SERIES BSDA SPECIFICATIONS AND MODEL NUMBERS | ||||||||
|---|---|---|---|---|---|---|---|---|
| Pipe Size |
Orifice Size |
Cv | MAX. Inlet Pres. PSI BARS |
MAX. Back Pres. PSI BARS |
MAX. Air Pres. PSI BARS |
MIN. Air Pres. PSI BARS |
PVC Body with PTFE Diaphragm Model No. |
|
| 1/4" | 5/16" | 1.1 | 100 6,90 | 25 1,72 | 100 6,89 | 40 2,76 | BSDA025T-NC-PV | |
| 1/2" | 1/2" | 3.4 | 100 6,90 | 25 1,72 | 100 6,89 | 40 2,76 | BSDA050T-NC-PV | |
| 3/4" | 5/8" | 5.8 | 100 6,90 | 25 1,72 | 100 6,89 | 40 2,76 | BSDA075T-NC-PV | |
| 1" | 3/4" | 6.3 | 100 6,90 | 25 1,72 | 100 6,89 | 40 2,76 | BSDA100T-NC-PV | |
| 1-1/2" | 1-1/4" | 17.0 | 100 6,90 | 25 1,72 | 100 6,89 | 40 2,76 | BSDA150T-NC-PV | |
Ordering Information
Note: For complete information request catalog page.
BSDA 025 T - NC - PV 025-1/4 NPT or BSP PTFE Body Material 050-1/2 NPT or BSP Diaphragm PV-PVC 075-3/4 NPT or BSP TF-PTFE 100-1 NPT or BSP PP-Polypro 150-1½ NPT or BSP PF-PVDF/Kynar
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Kynar® is a registered trademark of Arkema., Corzan® is a trademark of Noveon., Geon® is a registered trademark of the Geon Co., Copyright© 1997-2007 Plast-O-Matic Valves, Inc.
Fail-Dry® is a registered trademark of Plast-O-Matic Valves, Inc.