Multi-hole orifice plate is similar to centric orifice plate however, in its disc there are more orifice holes. Use of multi-hole orifice plate is limited by β = d/D, the orifice plate is made for β = 0.4 up to 0.65. Design of the multi-hole weld-in orifice plate consists of straight lengths of piping downstream the plate. Multi.-hole weld-in orifice plate has the advantages such as material savings on the flanges and subsequently minimized leakage in the flanged joint.

Pressure differential tapping can be chamber, individual or flanged. Due to production technology of the weld-in orifice plate chamber tapping are usually used for inside diameters DN 50 up to DN 80. Upon agreement with the customers outlets of differential pressure are always customized to various options of attachment of primary element to the measuring circuit.

Multi-hole orifice plate is manufactured for nominal diameters ranging from DN 15 up to DN 1,000 and for nominal pressures up to PN 320. For the production of weld-in design of orifice plates there are mostly used standard combinations of carbon and stainless steels for the measurement of fluid flow and refractory steel for the measurement of steam flow e.g. alloyed steels 14MoV6-3/15 128, 10CrMo9-10/11CrMo910, 13CrMo4-5, 16Mo3 and X10CrMoVNb9-1. Multi-hole orifice plate is manufactured either as a working meter or, as a specified meter with metrological verification complying with the technical particulars and conditions of pattern approval.

Except for advantages of centric orifice plates (such as simplicity, replaceability and reliability), multi-hole weld-in orifice plates also have the advantage of smaller installation lengths enabling wider possibilities of their use. Passage of the measured fluid through several tapered cross-sections reduces demand on minimal straight lengths of piping downstream and upstream the orifice plate necessary for proper functioning of this type of meter.

Multi-hole weld-in orifice plate has great advantages such as high operational reliability and applicability in measurement of fluid, gas and steam flows. Weld-in design of the multi-hole orifice plate is especially suitable for use in high pressure parts of piping systems and distributions (high pressure steam, feed water) or in piping systems needing seismic resistance with limited possibilities of keeping straight lengths of piping that are needed by centric orifice plate or other types of primary elements.

Multi-hole orifice plate design enables using straight lengths of piping "downstream" the orifice plate minimally 4D long. Orifice plates with chamber and individual tapping can be manufactured in the ranges of DN and PN different than stated above.

Welded-in design of multi-hole orifice plate can be incorporated both in vertical and horizontal piping.