Pressure Vessel Fittings
swtwater.com Vacuum Breakers
SWTs Machined Vacuum Breakers are available with a machined PVC or CPVC body and thread or spigot connection. They automatically vent a closed system to atmosphere when a vacuum of approximately 2-inches of water @ 4°C (5 mbar or 0.07 psi) is present.
 
SWT Machined PVC Vacuum Breakers
SWT Machined Vacuum Breaker dimensions
SEE TABLE BELOW FOR
PART NUMBERS AND DIMENSIONS.
 
TECHNICAL SPECIFICATIONS
PVC Body
Max. Operating Temperature: 140°F (60°C)
Max. Operating Pressure: 125 psi
CPVC Body
Max. Operating Temperature: 160°F (71°C)
Max. Operating Pressure: 150 psi
MATERIALS OF CONSTRUCTION
Machined PVC or CPVC body, acetal diaphragm, stainless steel spring, Buna-N seals
INSTALLATION
Install the vacuum breaker at the highest point in the system using a reducing tee. (See below for recommended reducing tees from SWT.) SWT Vacuum Breaker installation diagram
 
Part Number Body
Material
Connection

Dim A
Diameter

Dim B
Length
SM-VB-12SP PVC 1/2 inch Spigot 1 inch 1-1/4 inch
SM-VB-34SP-CPVC CPVC 3/4 inch Spigot 1-3/16 inch 1-1/2 inch
SM-VB4P PVC 1-1/2 inch MNPT 2 inch hex nut 2-1/4 inch
SM-VB4P-SPIG PVC 1-1/2 inch Spigot 2 inch 2-1/4 inch
SM-VB4P-CPVC CPVC 1-1/2 inch MNPT 2 inch 2-1/4 inch
SM-VB4P-CPVC-SPIG CPVC 1-1/2 inch Spigot 2 inch 2-1/4 inch
 
 
REDUCING TEES
For 1-1/2 inch MNPT vacuum breakers... For 1-1/2 inch spigot vacuum breakers...
Threaded Tee for installation with SWT Vacuum Breakers Socket Tee for installation with SWT Vacuum Breakers
Part No. Description Part No. Description
802-015 PVC Tee for 1.5 inch pipe 801-015 PVC Tee for 1.5 inch pipe
802-251 PVC Tee for 2 inch pipe 801-251 PVC Tee for 2 inch pipe
802-291 PVC Tee for 2.5 inch pipe 801-291 PVC Tee for 2.5 inch pipe
802-337 PVC Tee for 3 inch pipe 801-337 PVC Tee for 3 inch pipe
802-419 PVC Tee for 4 inch pipe 801-419 PVC Tee for 4 inch pipe
       
802-015C CPVC Tee for 1.5 inch pipe 801-015C CPVC Tee for 1.5 inch pipe
802-251C CPVC Tee for 2 inch pipe 801-251C CPVC Tee for 2 inch pipe
802-291C CPVC Tee for 2.5 inch pipe 801-291C CPVC Tee for 2.5 inch pipe
802-337C CPVC Tee for 3 inch pipe 801-337C CPVC Tee for 3 inch pipe
802-419C CPVC Tee for 4 inch pipe 801-419C CPVC Tee for 4 inch pipe
 
 
VACUUM PROTECTION & FLEX CONNECTORS
Fiberglass/composite pressure vessels are rated for an internal negative pressure of 5-inches Hg (17 Pa) vacuum below atmospheric. If negative pressure could ever exceed 5-inches Hg (17 Pa), an adequate vacuum breaker must be installed between the pressure vessel inlet and any valves (see illustration right). For enclosed tank applications, the vacuum breaker should be installed at the highest location in the system plumbing.

System connections to the pressure vessel must accomodate vertical expansion between side, top, and bottom openings. Either flexibility in piping or flex connectors, as shown here, are recommended.
SWT Vacuum Breaker and Flex Connector installation diagram
 
 
 
Safe Water Technologies, Inc.
996 Bluff City Boulevard
Elgin, IL 60120 USA
 
 
Telephone: +1.847.888.6900
Facsimile: +1.847.888.6924
E-mail: info@swtwater.com
http://www.swtwater.com

Last Updated: January 3, 2017