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STV TEST &
BLOCKING VALVE
STV test/block valve is installed on downstream
side of steam trap. During normal operation, valve is
in open position with unrestricted flow through trap
into the return system.
One quarter turn (90°) of STV blocks flow from return and
vents trap discharge to atmosphere. Provides quick, visual
check of trap operation.
STV SERIES
COMBINATION TRAP TEST &
BLOCKING STEAM VALVE
Pressures To 250 PSIG (17.2 barg)
Temperatures to 406°F (208°C)
Visual Steam Trap Test — Provides for quick visual
examination of steam trap discharge.
Compact Body — Small size facilitates installation and
operation in tight spaces.
Stainless Steel Internals — High quality materials provide
long service life and protection against corrosion.
Repairable — All parts are easily replaceable.
Large Size Test Vent — Vent passage in ball is large
enough to provide true determination of trap discharge.
Safety Designed — Bottom loaded, pressure retaining
stem and packing nut threaded to body provides extra
margin of safety.
Reduces Labor Costs — Eliminates need to install and
maintain separate blocking and test valves.
Minimizes Risk of Connection Leaks — Eliminates the
need for numerous fittings.
APPLICA TIONS
●
Test Steam Traps
●Sample Fluids or Gases from Process Lines
OPTIONS
●
Stainless Steel Latch-lok Handle
●Extended Handle
Canadian Registration # OCO591.97
OPERA TION
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Inches (mm) Weight
Size A B C D E F G Lbs. (kg)
1
/2” .375 .156 .281 2.26 1.20 2.17 4.25 1.1
(15) (10) (4) (7) (57) (30) (55) (108) (.5)
3
/4” .531 .218 .281 2.83 1.49 2.45 4.25 1.4
(20) (13) (6) (7) (72) (38) (62) (108) (.64)
Connections: 1/4" NPT Blowdown
1/2" and 3/4" NPT Inlet & Outlet
M
AXIMUM OPERATION
CONDITIONS
PMO: Max. Operating Pressure 250 psig (17 barg)
TMO: Max. Operating Temperature 406°F (208°C)
PMA: Max. Allowable Pressure 250 psig (17 barg)
TMA: Max. Allowable Temperature 406°F (208°C)
MATERIALS OF
CONSTRUCTION
Body: . . . . . . . . . . . . . . . . .ASTM A216 WCB Carbon Steel
(Blk oxide & oil coat)
Adapter: . . . . . . . . . . . . . .12L14C.R.S. (Blk oxide & oil coat)
Ball: . . . . . . . . . . . . . . . . . . . . . . . . . . . .316 Stainless Steel
Seat: . . . . . . . . . . . . . . . . . . . .25% Mineral Fill Virgin Teflon
Stem: . . . . . . . . . . . . . . . . . . . . . . . . . . .316 Stainless Steel
Insulator: . . . . . . . . . . . . . . . . . . . . . . . .Plastisol (Vinyl grip)
Packing Gland: . . . . . . . . . . . . . . .Carbon Reinforced Teflon
Packing Nut: . . . . . . . . . .12L14 C.R.S. (Blk oxide & oil coat)
Handle Nut: . . . . . . . . . . . . . . . . . . . . . . .Steel (Zinc plated)
Handle: . . . . . . . . . . . . . . . . . . .11 Ga. C.R.S. (Zinc plated)
Thrust Washer: . . . . . . . . . . . . . . . .Glass Reinforced Teflon
Body Seal: . . . . . . . . . . . . . . . . . . . . . . . . . . . .Virgin Teflon
STV SERIES
COMBINATION TRAP TEST &
BLOCKING STEAM VALVE
DIMENSIONS
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STV TEST &
BLOCKING VALVE