Pressure changes from protected equipment to a pressure relief valve (PRV) and from a PRV to the final relief effluent location are determined to allow an evaluation of the effect of the pressures on the…
Read More »In our experience, rented, leased or purchased temporary equipment as well as vendor-supplied skids that are intended for either temporary or normal use, have been found to have numerous issues pertaining to the overpressure protection…
Read More »In a reciprocating compressor, a failure of the packing material around the rod can allow high pressure gases from the cylinder to enter into the distance piece that separates the cylinder housing from the compressor…
Read More »API Standard 520 Part 1 9th Edition1 Annex B §B.3.1.2 provides an expression in equation B.13 for the isentropic expansion coefficient in terms of thermodynamic state variables, to be evaluated anywhere along the isentropic path,…
Read More »A subcooled yet flashing liquid, in which the vapor pressure is less than the relief pressure yet greater than the superimposed backpressure, represents an occasional non-ideal sizing condition, as the flow is neither fully liquid…
Read More »In a previous Fireside Chat, Orifice Flow Calculation Basis, we provided information on the flow of compressible fluids through sharp-edged orifices. While that topic was primarily geared toward the flow of gases through an orifice…
Read More »The 2nd edition of the CCPS Guidelines for Pressure Relief and Effluent Handling1 recommends the work of Darby2 for use in evaluating relief piping systems. We have already touched on the recommendations regarding roughness factors. …
Read More »There are a number of methods available for estimating the capacity of a pressure relief valve for a two-phase relief fluid.1,2 One primary distinction among these methods is the means for representing fluid property behavior,…
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