HWMA2 USER INSTRUCTIONS ENGLISH - 06/16
Page 10 of 39
72
62
66
66
64
64
64
62
57
66
56
60
60
58
58
58
56
51
74
64
68
68
66
66
66
64
59
67
57
61
61
59
59
59
57
52
Sound pressure readings are for information only and are not subject to guarantee by Flowserve/IDP.
Decibel readings do not include driver or system noise.
Pump tested at 100% of the best efficiency point at max.impeller diameter with water.
dB correction for combining noises (pump+motor)
Add to the higher level to obtain
the combined noise level,dB
Note :
1) The values showed are measured at a distance of 1 mt. (horizontally) from major pump
surfaces and 1.5 mt. above the floor.
2) The values shown are expressed in dB (A)
3) For Noise Test Procedure refer to Works Standard L-109
4) The values shown have been derived from actual noise-test data and are based on the following conditions:
-
Equipment is located in a free field above a reflecting plane in which the reductionin noise level
in all directions is 6db in each octave band for each doubling of distance.
-
Background noise is 10dB minimum below all noise levels in each octave band.
-
The values shown are at a distance of 1 meter (horizontally) from the major pump surface and
1,5 meters above the floor, using a standard pressure reference of 0,00002 newton per square meter.
-
Overall noise level, dB(A) is determined at points of maximum noise level and the values of all
mid-band frequences are basis A scale readings.
When the required condition flow is outside the range of 75 to 125% BEP, a part load correction (PLC) must be
added to the noise level as follows:
Percent of BEP @
required impeller
diameter
PLC in
dB
74 to 62 or 126 to 136
+1
61 to 50 or 137 to 150
+2
49 to 38
+3
37 to 25
+4
Octave MID BAND frequency [Hz]
0
1
2
4
6
9
10
3600 rpm
1
0.5
0
3
2.5
2
1.5
levels to be combined, dB
Difference between two
3000 rpm
1500 rpm
1800 rpm