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.