Linde HPR-2 Manual page 11

Noise reduction. SPU silencer
SPU silencer function
>> Reduction of pressure pulsations over the entire
operating range
>> Reduction of noise emission by approx. 50 %
(equals approx. 3 dB(A))
>> Reduction of volume flow fluctuations
>>
No impairment of efficiency
>> Ready for use immediately, no maintenance required
>> Simple and rugged design
>> Minimum increase in weight and volume
The following diagrams illustrate the immediate effect of pulsation level reduction via SPU on the sound pressure level and there-
fore the perceived noise emission.
Comparison of sound pressure levels for a HPR 75-02 pump with and without SPU
at an operating pressure of 350 bar
bei einem e rieb ruck von 50 ba
1000 1500
Drehzahl [U/min]
Comparison of resulting noise emission
Shown in 2 dB(A) steps over a typical diesel engine operating speed range.
Geräusch in 2dB(A) Schritten
Noise Level in 2 dB(A) steps
ar t blich
conventional
it S
with SPU
mi with SPU
2000 2500
Speed [rpm]
Kabinengeräusch
Cabin Noise
Dieseldrehzahl (typischer Betriebsbereich)
Diesel speed (typical operating range)
HPR-02 with SPU
bei einer Drehzahl von 2500 U/min
U
50 100
Außengeräusch
Outside Noise
at a speed of 2500 rpm
150 200
Pressure [bar]
Druck [bar]
with
mi U
SPU
250
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