Get Your Copy of ISO 5167-2 Orifice Plates PDF and Improve Your Flow Measurement Skills
The range of diameter of orifice plates is d = 0.10mm to d = 0.80mm. The diameters are different depending upon the quality of the material and the material as per the line pressure and are listed in Table 9.1. In the case of the material used, the diameter of the tapped bore, the smallest bore of the orifice plate is 0.1873 mm and the largest is 0.7164 mm. There is a tap on either side of the orifice plate and they can be either round or slotted, depending on the required service (pressure and thermal) rating of the orifice plate.
Iso 5167 2 Orifice Plates Pdf Download
The plates are normally machined out of a suitable metal e.g., copper, aluminium, stainless steel or nickel-steel. The selection of the material is governed by the conditions, in terms of, e.g., temperature, the pressure of the fluid, and the size and number of orifices. Generally, the plates are constructed out of aluminium or copper and the diameter of the plate is 75% of the diameter of the tapped bore. To avoid the effects of thermal growth, the tapped bore size is larger than the final diameter of the orifice plate.
6. Tapped bores of the orifice plate The upstream pressure tap for 0.20 mm through 0.80 mm, the downstream pressure tap for 0.14 mm through 0.77 mm, and the center tap for 0.20 mm through 0.80 mm. The tapped bores in the orifice plate are as shown in Table 9.1. The tapped bore diameters increase with increasing of material and line pressure. The tapped bore diameters include any distortions caused by drilling. Orifice plate thickness is generally 2 mm e.g., 2.5 mm for copper and 0.75 mm for aluminium. In the case of copper, the tapped hole diameter and thickness is 0.1873 mm and 0.016 mm respectively. The tapped bore of the orifice plate is larger than the diameter of the bored hole in the pipe to ensure adequate leak free performance. The tapped bores are generally machined in a turning centre and are drilled by mechanical drilling or by electrical discharge machining.