POSITIVE SHUT-OFF CAPILLARY LEAK STANDARDSPSO Calibrated Leaks for all Gases

The PSO Model “ZERO-DEAD-VOLUME” CAPILLARY LEAKSFOR ALL GASES
These capillary-type calibrated leaks use VTI’s proprietary Positive
Shut-Off (PSO) valves to provide instant on-off operation withessentially no dead volume. This eliminates any gas burst when thevalve is opened. The valve’s dead volume is only 0.0001 cc compared
to as much as 1 cc or more in some valves. The PSO-valve Leaks also
minimize gas depletion rates and provide longer life even at high flowrates. Their leak-rate control element is a crimped stainless steel
capillary suitable for use with all gases.
The Positive Shut-Off Calibrated Leaks are available with an integral gas
reservoir and can be provided with any gas. They are also available
without a gas cylinder for use with an external gas source. Operation ofthe valve can be manual, pneumatic or electrical.
The unique features of these proprietary PSO Calibrated Leaks result in their use in a wide variety of applications. Theyare extensively used for verification tests and calibration of Leak Testing Systems, usually with automated valve operation
and usually with an external gas source rather than a reservoir. They are also used frequently to flow gas at a controlledrate into a process chamber or research apparatus, or to “dope”
another gas stream. For mass spectrometer analysis of gases that are
at high pressures, the PSO-valve Leaks are used to reduce the pressure
and provide a sample rapidly with no gas burst.
VTI has also developed a Mass Spectrometer Calibrator using the PSO
Calibrated Leak and a reservoir of mixed gas (3% Helium, Krypton,
Xenon and Hydrogen, 1.8% Nitrogen and 86% Argon). This Mixed-gas
Calibrator provides a convenient and accurate way to tune the peakposition and height for masses ranging from 1 to132 amu. The low
dead volume of the valve eliminates any gas burst into the system andconserves the gas mix, thus providing a long operational lifetime.

Choosing the PSO Leak Standard
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ESSENTIALLY NO DEAD VOLUME – no pressure burst on opening.

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FAST RESPONSE – provides instant on-off operation.

LOW DEPLETION RATES – allows high flow rate applications anduse with expensive gases.
CRIMPED METAL CAPILLARY LEAK ELEMENT – can use any gas.
AUTOMATIC OPERATION – available for integration into systems.
LONG TERM STABILITY – valve is closed except during use.
MEETS ISO REQUIREMENTS - NIST-traceable, A2LA-accredited
Calibration Certification.

Drawing of the PSO-valve Leak

VTI’s Calibration
Laboratory is Accreditedby the American
Association forLaboratory Accreditation.

As the major manufacturer of Calibrated Leaks for all gases, allleak rates, and all makes of leak detectors, VTI supplies themworldwide to users, distributors, and other manufacturers.
These Accu-Flow™ Leak Standards are recognized internationallyfor their superior quality construction and calibration.

VACUUM TECHNOLOGY INCORPORATED Oak Ridge, Tennessee USA
Toll-Free: 800-704-4774

Fax: 865-481-3788
sales@vacuumtechnology.com
www.vacuumtechnology.com

POSITIVE SHUT-OFF CAPILLARY LEAK STANDARDSPSO Calibrated Leaks for all Gases
ORDERING INFORMATION
For an order or quotation request for a PSO Leak, please provide the Part Number constructed from the codes provided,and also confirm the Fittings by name and function to avoid errors. In addition, please describe the Gas or Gas Mix to beused. Any dimensional requirements should also be noted.
For the PSO Leaks with a Reservoir, please also specify the specific Leak Rate requested and your preferred leak-rate
units. For PSO Leaks without a reservoir to be used at one leak rate and pressure, please provide the specific Leak Raterequested, plus the Inlet Pressure that you will use from your gas line (corresponding to that Leak Rate). In either case,the Outlet Pressure should be stated as “Flow into Vacuum” (the usual) or “Flow into Atmosphere” (1 atm.). Also, theManufacturing Variance (“Tolerance”) that you can allow on that Leak Rate should be specified as +/- 40% (the normalallowance), or as +/- 15% (the “Special-Range Variance”), for which there is an additional cost and an “-SR” added to the-5part number. An example specification is 2.0x10 atm-cc/sec +/- 40%. In both cases, the leak rate provided will be as
close as we can make it to your specified rate, and the actual rate, as calibrated, will be recorded on the Calibration Tag
and the Certifications.
PSO Leaks without a reservoir can also be calibrated atmultiple inlet pressures to provide a range of adjustable-5
leak rates, for example covering values from 1 to 9x10
atm-cc/sec using three pressures from 15 to 200 psig. VTI
provides a curve of Leak Rate vs. Pressure based on thecalibrations. This allows the leak rate to be changed bychanging your pressure and allows exact leak rates to beselected without the limitation of the manufacturing
variance. For these adjustable-rate PSO Leaks, VTI canadvise on the leak-rate range achievable based on youravailable pressure range.

PART NUMBER BUILD-UP
The PSO Part Numbers are constructed as follows:

For leaks without a reservoir:

PSOT-X-NA-BB-YYYY-ZZZZ-OOOO

EXAMPLE GASES and CODES – (BB)
Please contact us with other gas requirements.
Helium (HE), Argon (AR), Nitrogen (N2), Hydrogen (H2),Carbon Dioxide (CO2), Oxygen (O2), Air (AIR), Methane(CH4), Sulphur Hexafluoride (SF6), Refrigerants (“R”#),
Xenon (XE), Deuterium (D2), Mixed gases (MIX).

EXAMPLE FITTINGS and CODES
Contact VTI for other fitting requirements.
Code:4FVCR
4MVCR
MCFF
2CFF
KF16
KF25

Description:¼” Female VCR¼” Male VCR
1.33” OD Mini Conflat Flange
2.75” OD Conflat Flange¾” OD ISO Flange
1” OD ISO Flange

For leaks with a reservoir:

OTHER ORDERING CODES

PSOT-X-NA-BB-YYYY-ZZZZ-RRRR-FVO
where T = operation type (M=Manual, A=Air, S=Solenoid).
where X = the code for the Leak Rate Range required.
where N = the code for the number of calibration points.
Where A = calibration method (C for He, P for other gases)
where BB = the code for the Gas to be used
where YYYY = the code for the INLET fitting required.
where ZZZZ = the code for the OUTLET fitting required
where OOOO = the code for the optional port fitting,where RRRR = the code for the reservoir,
and FVO = Fill Valve Option: WFV or MFV (Bakeable)

X Code:Leak Rate Range:

2345
6

1.0 to 9.9X10-2 amt-cc/sec-3
1.0 to 9.9X10 amt-cc/sec
1.0 to 9.9X10-4 amt-cc/sec-5
1.0 to 9.9X10 amt-cc/sec
1.0 to 9.9X10-6 amt-cc/sec

R Code:Reservoir Size:

150DOT
300DOT

150cc Reservoir tested per DOT
300cc Reservoir tested per DOT

1000DOT

1000cc Reservoir tested per DOT

Other leak rates and reservoir sizes available!

EXAMPLE PART NUMBERS
PSO-valve Leak with a Reservoir

PSO-valve Leak without a Reservoir

Part No.: PSOM-6-AR-4FVCR-4MVCR-300DOT-MFVPart No.: PSOA-5-3C-HE-4FVCR-4FVCR-4FVCR

An Argon leak with manual valve operation, one specified-6
leak rate in the range of 10 atm-cc/sec, VCR fittings, 300cc
reservoir, and all-metal fill valve.

A Helium leak with an air-operated valve, calibrations-5
at 3 rates/pressures in the 10 leak rate range, andVCR fittings.

VACUUM TECHNOLOGY INCORPORATED Oak Ridge, Tennessee USA
Toll-Free: 800-704-4774

Fax: 865-481-3788
sales@vacuumtechnology.com
www.vacuumtechnology.com
PSO-DATA-09/2004-Rev1