These GPP Model Helium Calibrated Leak Standards have glass-permeation type leak elements and are the most common ones used to tune and calibrate helium mass spectrometer leak detectors, leak testing systems and vacuum systems. They are part of a family of Calibrators including the GPPT, GPC and CLP Models offered by VTI that cover leak rates from 10-12 up to 10-3 atm-cc/sec and larger. Those models are detailed in other brochures, and VTI’s experts are always eager to help you select the best model – technically and cost – for your application. Without obligation, of course.
The GPP Accu-Flow™ Calibrated Leaks are based on the principle that helium flows through certain materials at a measurable rate depending on the material thickness, driving pressure and temperature. Depending on the leak rate required in the GPP Leaks, the permeation material is Pyrex or Quartz.
The GPP Leaks feature an all-welded stainless steel construction for reliability. Most leaks require a shut-off “isolation” valve to zero the leak signal during tuning and calibration. VTI offers the GPP Leaks both with and without a Teflon®-packed stainless steel shut-off valve. The inlet port of the brand of leak detector or vacuum system determines the termination of the leak. The most common termination of the GPP Leaks is a 1-1/8″ diameter tube which mates directly to many Varian, Veeco and VIC leak detectors. All leaks are available with QF (NW, KF) and many other types of fittings.
All GPP Leaks are provided with certifications of the NIST-traceable calibrations performed in our A2LA-accredited Calibration Laboratory.
Why choose the GPP Calibrator?
WILL NOT CLOG – permeation leak element
LONG TERM STABILITY – low depletion rate
WIDE LEAK-RATE CHOICE – 10-5 to 10-9 range
NEVER NEEDS REFILL – lasts for years
SIMPLE TO OPERATE – minimal user training
MEETS ISO REQUIREMENTS – NIST-traceable, A2LA-accredited Calibration Certification
The GPP Calibrators can be ordered for a specified Helium Leak Rate within a wide range of values. When ordering or requesting a quotation, please provide the Part Number, confirm the Fitting needed, and state the specific Leak Rate requested including your preferred leak-rate units. Also, please specify the Manufacturing Variance (“Tolerance”) that you can allow on that Leak Rate. The usual manufacturing variance is +/- 40% of the requested rate. An example specification is 2.0×10-8 atm-cc/sec +/- 40%. Alternatively, the allowable values as manufactured can be specified as 1 to 3×10-x, 4 to 6×10-x, or 7 to 9×10-x in a Leak Rate Range listed below.
Also, a “Special Range” manufacturing variance is available of +/- 15% of the requested rate. For this special variance, an “-SR” is added to the end of the Part Number and there is an additional cost. In all cases, the leak rate provided will be within the selected manufacturing variance and will be as close as we can make it to your specified rate. The actual rate, as calibrated, will be recorded on the Calibration Tag and the Certifications.
Part Number Build Up
The GPP Series Part Numbers are constructed as follows:
where X = the code for the Leak Rate Range required
where YYYY = the fitting required
where ZZZ = the code for the reservoir size
Valve Requirements – the addition of a Fill Valve is required on all leaks in the mid 10-6 range and larger due to the higher fill pressures. In these cases, -WFV is added to the end of the part number. For leaks without a shut-off valve, -NV is added.
Example Fittings Available
Please contact us for other fitting requirements.
|118T||1-1/8″ OD Port Tube|
|4FVCR||¼” Female VCR|
|4MVCR||¼” Male VCR|
|MCFF||1.33″ OD Mini Conflat Flange|
|2CFF||2.75″ OD Conflat Flange|
|8T||½” OD Tube|
|KF16||¾” OD ISO Flange|
|KF25||1″ OD ISO Flange|
|KF40||1.5″ OD ISO Flange|
|118T/34T||1-1/8″ OD Tube with step to ¾” Tube|
|4MPT||¼” Male Normal Pipe Thread|
Leak Rates Ranges Available and Example Part Numbers
|Leak Rate Ranges Available for the GPP||Code for Leak Rate Range (X)||Code for Fitting (YYY)||Sugg’ed Reservoir Size||Code for Reservoir Size(YYY)||Example Part Number|
|(Specify a value in the range)|
|1.0 to 9.9×10-5 atm-cc/sec||5||KF25||1000||1000DOT||GPP-5-HE-KF25-1000DOT-WFV|
|1.0 to 9.9×10-6 atm-cc/sec||6||KF40||500||500DOT||GPP-6-HE-KF40-500DOT-WFV|
|1.0 to 9.9×10-6 atm-cc/sec||6||118T||500||300DOT||GPP-6-HE-118T-300DOT-WFV|
|1.0 to 3.0×10-6 atm-cc/sec||6||1/2T||300||300DOT||GPP-6-HE-1/2T-300DOT|
|1.0 to 9.9×10-7 atm-cc/sec||7||KF16||110||(Blank)||GPP-7-HE-KF16|
|1.0 to 9.9×10-8 atm-cc/sec||8||2CFF||110||(Blank)||GPP-8-HE-2CFF|
|1.0 to 9.9×10-9 atm-cc/sec||9||MCFF||110||(Blank)||GPP-9-HE-MCFF|
1.0E-5 to 9.9E-5 atm-cc/sec, 1.0E-6 to 9.9E-6 atm-cc/sec, 1.0E-7 to 9.9E-7 atm-cc/sec, 1.0E-8 to 9.9E-8 atm-cc/sec, 1.0E-9 to 9.9E-9 atm-cc/sec, Unknown
1-1/8" OD Tube, 1-1/8" to 3/4" OD Tube, 1.33" OD Conflat Flange, 1/4" Female NPT, 1/4" Female VCO, 1/4" Female VCR, 1/4" Male NPT, 1/4" Male O-Seal, 1/4" Male VCO, 1/4" Male VCR, 1/4" OD Tube, 1/4" Swagelok Compression Fitting, 1/8" Female NPT, 1/8" Male NPT, 1/8" Male O-Seal, 2.75" OD Conflat Flange, QF16 (KF16), QF25 (KF25), QF40 (KF40)
+/-10% of Target Leak Rate, +/-15% of Target Leak Rate, +/-20% of Target Leak Rate, +/-40% of Target Leak Rate – Standard, +/-5% of Target Leak Rate