Air-Operated PTFE Diaphragm Valves

Compact valves for corrosive and ultra-pure liquids in PVC, PTFE, Kynar^® & Polypropylene • ¼" through 1½" sizes

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 BSD works.

Designed for pressure 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 BSD provides the ultimate in non-leaching, contamination-free sealing. The standard valves are air pressure to open, with "fail safe" spring return to close. Line pressure assists in opening the valve, which results in lower than normal compressed air pressure. The BSD is not designed for vacuum service.

Series BSDA is Series BSD with an "attached" diaphragm, for pressure and drain applications. Because the diaphragm is attached, no inlet pressure is required to assist with opening.
Series BSDA is not designed for vacuum service.

Diaphragm Design

The standard diaphragm material is PTFE for the ultimate in purity, backed with Viton^® for the ultimate in strength and flexibility. The Viton^® side is not in contact with liquid. For unusually sensitive applications, an optional Kynar^® PVDF diaphragm can be placed between the PTFE and Viton^® for an additional barrier.

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 BSD 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 BSD DIMENSIONS
	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: Series BSDA with attached diaphragm for drain and low pressure applications has the same dimensions and specifications as Series BSD. Note 2: 1/8" & 3/8" sizes are also available on special order. Consult factory for details.

BSD 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:

Ordering Information

Note: For complete information request catalog page.

BSD (A)         025                  T  -  NC - PV

    Optional    025-1/4 NPT or BSP   PTFE     Body Material

    Attached    050-1/2 NPT or BSP   Diaphragm  PV-PVC

    Diaphragm   075-3/4 NPT or BSP              TF-PTFE

                100-1   NPT or BSP              PP-Polypro

                                                PF-PVDF/Kynar

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Kynar® is a registered trademark of Arkema., Corzan® is a trademark of Noveon., Viton® is a registered trademark of DuPont Dow Elastomers., Geon® is a registered trademark of the Geon Co.,

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