Autek AS, Hofgaardsgate 27, 3012 Drammen Phone: +47 32219200, Mail: mail@autek.no  

Rev. 4 ‐ 2013 

Restriction plates and critical orifices

Manufacture and design: • Single plates and multi plates • Orifice sizing, noise and

deflection calculated by Autek • General compliance with ISO

5167 and R.W Miller • Design according to a well

know standards • Exotic materials for demanding

services – Duplex, 6MO, Titanium (M650)

• High pressure solutions • Wide temperature ranges

Autek Restriction Orifices and Critical orifices are calculated according to the formulae detailed in R.W Miller’s Flow Measurement Handbook. The design and material follow the requirements in NORSOK and Statoil TR.

Autek have long experience in calculating bore, thickness and noise over the plate. Autek AS is certified according to ISO 9001:2008 and has procedures to meet customer’s requirement for offshore deliveries.

Autek restriction orifice is used to create a calculated pressure drop within a gas, vapour or liquid flow over the plate. A critical flow device is designed with the assumption that some fluids will reach sonic velocity trough the bore of the restriction. It is more predictable to archive sonic velocity trough the bore for a thick plate than a standard restriction orifice. Critical orifices are therefore typical thicker than a restriction orifice. They are designed as either single plate element for use with RF, RTJ, HUB or Compact flanges or as a spool piece with flange/ HUB connection in both ends. Each application is unique and requires a separate calculation to verify the right bore and thickness. Autek restriction plates and critical orifices are manufactured to meet strict industry standards and safety guidelines and are designed to meet the end users expectations.

        

Autek AS, Hofgaardsgate 27, 3012 Drammen Phone: +47 32219200, Mail: mail@autek.no  

Rev. 4 ‐ 2013 

ORDERING CODES

    Code  Description Note

  Product   FE  Flow Element Flow element  & restriction orifices     ‐     Element type  O  Orifice  Tapping  D 

A F R 

Direct tappingAnnular ch. Tapping Flange tapping Restriction (no tapping) 

    0 W T F H Z 

No tappingWeld end Threaded Flanged HUB Special 

100mm with flange rating and sch. According PCS is standard.  

    ‐     Connection 

dimension 005 (015) 075 (020) 001 (025) 015 (040) 002 (050) 003 (080) 004 (100) 006 (150) Etc. ZZZ 

0,5” (DN15)0,75” (DN20) 1” (DN25) 1,5” (DN40) 2” (DN50) 3” (DN80) 4” (DN100) 6” (DN150 Etc. Z=Special 

    ‐     Connection 

rating 0150 (0020) 0300 (0050) 0600 (0100) 0900 (0150) 1500 (0250) 2500 (0420) 4500 Etc. ZZZ 

ANSI Class 150# (PN20)ANSI Class 300# (PN50) ANSI Class 600# (PN100) ANSI Class 900# (PN150) ANSI Class 1500# (PN250) ANSI Class 2500# (PN420) ANSI Class 4500#  Z= Special 

    ‐     Bore  XX,XX  Bore mm    ‐     Face‐to‐Face 

dimension XX  Face‐to‐Face in mm

    ‐     Connection type  FF 

RF RTJ DN CF H ZZ 

Flat FaceRaised Face RTJ DIN standard Compact Flanges HUB Z=Special 

    ‐     Material  CS 

SS DX SD MO TI ZZ 

Carbon SteelSS 316, 316L Duplex (22Cr) Super Duplex (25Cr) 254 SMO (6MO) Titanium Z= Special