SKU: 97855834032

Critical Orifice Assembly

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Description

Critical Orifice AssemblyMeets or exceeds the following methods laws requirements: US EPA Method 5: Section 16. 2. 1. 1 (Selection of Critical Orifices) Section 16. 2. 2 (Critical Orifice Calibration) Product Description Critical Orifice is used to calibrate the dry gas meter (DGM) of various metering consoles. This calibration instrument is approved by the US EPA as calibration standard for calibrating a dry gas meter, in place of the wet test meter stated in Section 16. 1

 Meets or exceeds the following methods/laws/requirements:

 

US EPA Method 5:

  • Section 16.2.1.1 (Selection of Critical Orifices)
  • Section 16.2.2 (Critical Orifice Calibration)


Product Description

Critical Orifice is used to calibrate the dry gas meter (DGM) of various metering consoles.

This calibration instrument is approved by the US EPA as calibration standard for calibrating a dry gas meter, in place of the wet test meter stated in Section 16.1 of the US EPA Method 5, provided that the critical orifices are selected, calibrated, and used in accordance with the instructions included in Section 16.2.1 of the US EPA Method 5.


This product connects to the following (non-exhaustive) list of products from Aer Sampling:

  1. Aer Sampling Metering Consoles (sample inlet)
Other Applicable Documents:
N.A.

 

Product Specifications

Connection: 1/2-inch quick connect

Material: Brass with Ruby orifice

Sizes (nominal):

Catalog ID

Size

Orifice diameter

Choked flow rate

inch mm cfm LPM
PN-738 400
0.0400 1.0160 0.31 8.79
PN-739 480
0.0480 1.2192 0.46 12.97
PN-740 550 0.0550 1.3970 0.60 17.08
PN-741 630 0.0630 1.6002 0.80 22.61
PN-742 730 0.0730 1.8542 1.09 30.94


Weight (Gravitational):
 0.29 lbs / 0.13 kg

Packing Dimensions (Length x Width x Height):
English (inch): 3.1 x 1.0 x 0.9
Metric (cm): 7.9 x 2.5 x 2.4


Other Information

Avoid vibration and/or shock.
Consider buying a carrying case, PN-285 --- Empty Critical Orifice Box for storage and transportation.


Calibration of Critical Orifice
 

This critical orifice does not come calibrated. For factory calibration before your first use, please add PN-773 --- Calibration of Critical Orifice into your cart before checking out (for online/website order) or please contact our Regional Sales Office (for offline order).

A calibration certificate will be issued:

  • The critical orifices are calibrated according to US EPA Method 5 (US CFR Title 40, Part 60, Appendix A, Test Method 5) Section 16.2.2, using a dry gas meter calibrated according to US EPA Method 5, Section 10.3, and other reference instruments with calibrations traceable to the International System of Units (SI).

Aer Sampling recommends calibrating critical orifices at least once a year.

Aer Sampling's critical orifices shall only be calibrated in vacuum mode (i.e., critical orifice be upstream of the vacuum pump). Results from calibration in non-vacuum modes (i.e., critical orifice is downstream of the pump; pump is pushing gas into the critical orifice) are not comparable. Critical orifice must reach critical conditions to be usable.


Manufacturing Warranty and Technical Support

 

All our products come with a one-year warranty against manufacturing defects and one-month technical support for free. Please refer to our Frequently Asked Questions (FAQs) page for more details.



-----

Information presented here is subjected to Aer Sampling Group's terms and conditions.
In case of discrepancy between English version and the non-English version, the English version shall prevail.
Doc ID: AERHQWW-pn-738-en
Last revised (Excluding prices): 1; 08.22.22
Obsolete Catalog ID: -

Shipping Notes
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Exchange/Return Notes
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  • Final sale items are not eligible for returns or exchanges.
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SKU: 97855834032

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First the hoses do not connect together causing all kinds of vacuum leaks. There is no rifling in the diaphragm so oil leaks back up. Cheap piece of plastic
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Reviewed in the United States on June 9, 2022
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Pawtucket, US
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Great price
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Alan C
Grantham, US
★★★★★ 5
Give me a try I don’t think it’ll let you down
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Fort Morgan, US
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Won’t use another brand now that I’ve used these guys. Phenomenal brand, noticeable difference in the engine.
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