8 noise level – Flowserve MPT User Manual
Page 10
MPT USER INSTRUCTIONS ENGLISH 85392699 06-09
Page 10 of 41
®
1.8 Noise level
Attention must be given to the exposure of personnel
to the noise, and local legislation will define when
guidance to personnel on noise limitation is required,
and when noise exposure reduction is mandatory.
This is typically 80 to 85 dBA.
The usual approach is to control the exposure time to
the noise or to enclose the machine to reduce
emitted sound. You may have already specified a
limiting noise level when the equipment was ordered,
however if no noise requirements were defined, then
attention is drawn to the following table to give an
indication of equipment noise level so that you can
take the appropriate action in your plant.
Pump noise level is dependent on a number of
operational factors, flow rate, piping design and
acoustic characteristics of the building, and so the
values given are subject to a 3 dBA tolerance and
cannot be guaranteed.
Similarly the motor noise assumed in the “pump and
motor” noise is that typically expected from standard
and high efficiency motors when on load directly driving
the pump. Note that a motor driven by an inverter may
show an increased noise at some speeds.
If a pump unit only has been purchased for fitting with
your own driver then the “pump only” noise levels in the
table should be combined with the level for the driver
obtained from the supplier. Consult Flowserve or a
noise specialist if assistance is required in combining
the values.
It is recommended that where exposure approaches
the prescribed limit, then site noise measurements
should be made.
The values are in sound pressure level L
pA
at 1 m
(3.3 ft) from the machine, for “free field conditions
over a reflecting plane”.
For estimating sound power level L
WA
(re 1pW) then
add 14 dBA to the sound pressure value.
Typical sound pressure level, dBA, L
pA
at 1 m (3.28 ft) reference 20
µ
Pa (2.9x10
-9
psi)
3550 r/min
2900 r/min
1750 r/min
1450 r/min
Motor size
and speed
kW (hp)
Pump and
motor
dBA
Pump
only
dBA
Pump and
motor
dBA
Pump
only
dBA
Pump and
motor
dBA
Pump
only
dBA
Pump and
motor
dBA
Pump
only
dBA
<0.55 (<0.75)
71
66
64
62
64
62
63
62
0.75 (1)
74
66
67
62
67
62
63
62
1.1 (1.5)
74
68
67
64
67
64
65
64
1.5 (2)
77
70
70
66
70
66
66
66
2.2 (3)
78
72
71
68
71
68
68
68
3 (4)
81
74
74
70
74
70
70
70
4 (5)
82
75
75
71
75
71
71
71
5.5 (7.5)
90
77
83
73
76
73
72
71
7.5 (10)
90
78
83
74
77
74
73
72
11 (15)
91
80
84
76
78
76
74
73
15 (20)
92
83
85
79
80
79
76
75
18.5 (25)
92
83
85
79
80
79
76
75
22 (30)
92
83
85
79
81
79
77
75
30 (40)
100
85
93
81
84
80
80
76
37 (50)
100
86
93
82
84
80
80
76
45 (60)
100
87
93
83
84
80
80
76
55 (75)
100
88
95
84
86
81
82
77
75 (100)
100
90
95
86
88
81
83
78
90 (120)
100
90
95
86
90
81
85
78
110 (150)
100
91
95
87
91
83
86
79
150 (200)
101
92
96
88
91
83
86
79
200 (270)
(1)
(1)
(1)
(1)
(1)
83
(1)
80
300 (400)
-
-
-
-
(1)
84
(1)
81
(1)
Motors in this range are generally job specific and noise levels should be calculated based on actual equipment installed.
For 960 r/min reduce 1450 r/min values by 5 dBA.