IEC 60534-8-3:2010 establishes a theoretical method to predict the external sound-pressure level generated in a control valve and within adjacent pipe expanders by the flow of compressible fluids. This method considers only single-phase dry gases and vapours and is based on the perfect gas laws. It is assumed that the downstream piping is straight for a length of at least 2 m from the point where the noise measurement is made. The method is applicable to the following single-stage valves: – globe (straight pattern and angle pattern), – butterfly, – rotary plug (eccentric, spherical), – ball, and – valves with cage trims. Specifically excluded are the full bore ball valves where the product FpC exceeds 50 % of the rated flow coefficient. This third edition cancels and replaces the second edition published in 2000. This edition constitutes a technical revision. The significant technical changes with respect to the previous edition are as follows: – predicting noise as a function of frequency; – using laboratory data to determine the acoustical efficiency factor.<\/p>\n
| PDF Pages<\/th>\n | PDF Title<\/th>\n<\/tr>\n | ||||||
|---|---|---|---|---|---|---|---|
| 6<\/td>\n | English CONTENTS <\/td>\n<\/tr>\n | ||||||
| 8<\/td>\n | INTRODUCTION <\/td>\n<\/tr>\n | ||||||
| 9<\/td>\n | 1 Scope 2 Normative references <\/td>\n<\/tr>\n | ||||||
| 10<\/td>\n | 3 Terms and definitions <\/td>\n<\/tr>\n | ||||||
| 11<\/td>\n | 4 Symbols <\/td>\n<\/tr>\n | ||||||
| 14<\/td>\n | 5 Valves with standard trim 5.1 Pressures and pressure ratios <\/td>\n<\/tr>\n | ||||||
| 15<\/td>\n | 5.2 Regime definition <\/td>\n<\/tr>\n | ||||||
| 16<\/td>\n | 5.3 Preliminary calculations <\/td>\n<\/tr>\n | ||||||
| 17<\/td>\n | 5.4 Internal noise calculations Tables Table 1 \u2013 Numerical constants N Table 2 \u2013 Typical values of valve style modifier Fd (full size trim) <\/td>\n<\/tr>\n | ||||||
| 19<\/td>\n | Table 3 \u2013 Overview of regime dependent equations <\/td>\n<\/tr>\n | ||||||
| 20<\/td>\n | Table 4 \u2013 Typical values of An and Stp <\/td>\n<\/tr>\n | ||||||
| 21<\/td>\n | 5.5 Pipe transmission loss calculation Table 5 \u2013 Indexed frequency bands <\/td>\n<\/tr>\n | ||||||
| 23<\/td>\n | 5.6 External sound pressure calculation Table 6 \u2013 Frequency factors Gx (f) and Gy (f) <\/td>\n<\/tr>\n | ||||||
| 24<\/td>\n | 5.7 Calculation flow chart 6 Valves with special trim design 6.1 General 6.2 Single stage, multiple flow passage trim Table 7 \u2013 \u201cA\u201d weighting factor at frequency f <\/td>\n<\/tr>\n | ||||||
| 25<\/td>\n | 6.3 Single flow path, multistage pressure reduction trim (two or more throttling steps) Figures Figure 1 \u2013 Single stage, multiple flow passage trim <\/td>\n<\/tr>\n | ||||||
| 26<\/td>\n | Figure 2 \u2013 Single flow path, multistage pressure reduction trim <\/td>\n<\/tr>\n | ||||||
| 27<\/td>\n | 6.4 Multipath, multistage trim (two or more passages and two or more stages) <\/td>\n<\/tr>\n | ||||||
| 28<\/td>\n | Figure 3 \u2013 Multipath, multistage trim (two or more passages and two or more stages) <\/td>\n<\/tr>\n | ||||||
| 29<\/td>\n | 7 Valves with higher outlet Mach numbers 7.1 General 7.2 Calculation procedure <\/td>\n<\/tr>\n | ||||||
| 30<\/td>\n | 8 Valves with experimentally determined acoustical efficiency factors <\/td>\n<\/tr>\n | ||||||
| 31<\/td>\n | 9 Combination of noise produced by a control valve with downstream installed two or more fixed area stages <\/td>\n<\/tr>\n | ||||||
| 32<\/td>\n | Figure 4 \u2013 Control valve with downstream installed two fixed area stages <\/td>\n<\/tr>\n | ||||||
| 33<\/td>\n | Annex A (informative) Calculation examples <\/td>\n<\/tr>\n | ||||||
| 34<\/td>\n | Table A.1 \u2013 Calculation: examples 1 to 6 <\/td>\n<\/tr>\n | ||||||
| 41<\/td>\n | Table A.2 \u2013 Calculation: example 7 <\/td>\n<\/tr>\n | ||||||
| 48<\/td>\n | Bibliography <\/td>\n<\/tr>\n<\/table>\n","protected":false},"excerpt":{"rendered":" Industrial-process control valves – Noise considerations. Control valve aerodynamic noise prediction method<\/b><\/p>\n |