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Find Precision Flow Orifice

We stock Silicon orifices with diameters as low as 0.001"

Sapphire orifices with diameters from 0.003" to .033"

and SS orifices with diameters 0.030"- 0.080"

No matter what flow specification, there is an orifice within a few percent of the requirement.

Universal Microsystems
Universal Microsystems
3300 Victor Court
Santa Clara, CA 95054
Sales@flowrestrictor.com
408-727-1313

We use a three digit ID code to specify the required orifice

If you know the required diameter, find the ID in the table below

If you know the nitrogen flow at inlet pressure P_i =20 psig, also find it in the table below

If P_i differs from 20 psig, calculate it by multiplying the required flow by 34.7/(P_i+14.7)

If the gas is not nitrogen, divide the required flow by K in the table below

Stainless Steel Orifices use the ID of Fxx where xx is the diameter in .001"
F05, and F30-F-80 available
N₂ @ 20 psig = 13.4(xx)²

If outlet pressure is > half inlet pressure use
Formulas

Table of stock Silicon and Sapphire Orifices
vs orifice diameter and flow of nitrogen at 20 psig

Nxx orifices have beveled inlet shape (higher flow) compared to Rxx orifices with flat inlet shape

Silicon Orifices require VS or KS in part number ID, sapphire and SS require FS
Caution, silicon orifices should not be used in exhaust streams from chambers with flourinated plasmas