How reasonable control of the air compressor room noise

  With the industry and the rapid development of transportation . Noise pollution is worsening , harm to human health , affecting people’s normal life , work and rest. Compressor plant is composed of one or more compressors , machinery, mining, chemical, metallurgical and other industrial sectors noise pollution is more serious workshop. Below Ulan air compressor factory workshop, for example , to talk about noise prevention and comprehensive measures . Factory workshop has 2L-10/8 air compressor 2, covers an area of 66m, each machine 740r/min, the whole weight 1700kg. Noise processing is not performed before the actual workshop noise 95Db (A) and 101Db (C), exceeding the national standard 5dB (A) above , the operator of the health of workers caused harm.

Install hanging acoustic panels

    According to the principle of acoustic treatment , hanging in space absorber . The noise the machine hit sound-absorbing material , some sound can be absorbed , so that the reflected sound energy weakened, the operator heard only from the sound source via the shortest distance to the direct sound and the weakening of emission sound , then the total the noise level is reduced.

Acoustic board design constructed : Central liner providing a layer of recycled fabric, each shop 5cm thick double-sided fine glass ( density take 25kg / m), outsourcing plastic screens and cotton lun stitching molding. This acoustic panels hanging in the shop at the top ( representing approximately 70% of the ceiling area ) divided into 10 , each about 2m. After taking several steps above , the measured noise compressor workshop 85dB (A), a total reduction 10dB (A).

To control noise in the transmission

    Main methods of insulation between attenuation and acoustic enclosures and other regional measures airtight .

In order to observe the operation and maintenance of the workers in the shop built into the side of a soundproof room 33m . With 240mm thick insulation between the brick , outside plus wiping 10mm thick cement plaster , in the face of the wall between the air compressor installed on doors and windows , shown in Figure 3, the door with a single door , the door in order to reduce weight and help sound insulation, designed to minimize the area of the door , the door size of 1900 × 740 × 80mm. Multi-layer composite plate structure doors , door and door frame joints with a rubber strip seal. Windows are double wooden frame fixed windows . To avoid resonance , glass thickness with 4mm and 6mm, two spacing of 80 ~ 100mm, using the slope angle mounting , an area of 1500 × 1010mm. Same as above 20m ceiling hanging sound absorbing plate .

Sound absorption and sound insulation testing.

    Between compressor noise 85dB (A), reducing the 10dB (A), to achieve a national " industrial enterprises noise control design specifications" required eight-hour work day noise does not exceed 90dB (A) requirements. Acoustic room noise is 62dB (A), sound insulation value of 33dB (A), to achieve a national " industrial enterprises noise control design specifications " (GBJ87-85) provides that " a telephone control room " noise does not exceed 70dB ( a) requirements , thereby protecting the health of workers , to meet the requirements of the working environment quiet .

The noise generated by the compressor sound source analysis

  Mainly by the inlet air compressor noise , radiation outlet aerodynamic noise , structural noise, mechanical noise and the driver as well as multiple sound sources superimposed noise and other components.

Compressor workshop comprehensive measures of noise

Noise source control

    Overall noise compressor intake noise accounts for a large proportion , so the installation of the intake silencer is the primary means of controlling the overall noise . Since the air compressor intake noise substantially low , so use with insertion tube and microplate composite expansion chamber muffler

Installing variable cross-section exhaust pipe

    Air compressor tank vent pipe sections to the exhaust pressure pulsation flow by the action of vibration and radiated noise , in addition to operating personnel can affect the health of the surrounding , but also lead to structural fatigue, therefore , recommend the use of variable cross-section exhaust pipe . Installed in the exhaust pipe after the throttle plate , can flow fluctuation was significantly inhibited , thereby reducing vibration and noise radiation. The plate attached to the container in the vicinity of the pipe connection , which is equivalent to the resistive element , the pulsating flow limiting play , while the cross section of the pipe is changed in the acoustic boundary conditions, restrictions pipe standing wave formation, thereby reduce vibration and noise radiation. Figure 2 general admission aperture diameter D d 0.43 to 0.5 times the plate thickness h is 3 ~ 5mm.

Damper installed in the bottom of the base

    Depending on the machine , and the total weight of machine 1700kg, speed 740r/min, using JG rubber vibration isolators . By the W = 1700/4 = 425kg, therefore , the choice of four JG3 -7 type shock absorber, damping theoretical efficiency of 93.3% , the installation uses the M16 bolts.

Institutional strengthening component repair and maintenance , reducing the impact of the components inside the machine , friction noise.