身處羅茨鼓風(fēng)機(jī)領(lǐng)域得人應(yīng)當(dāng)都懂，噪聲是羅茨鼓風(fēng)機(jī)生產(chǎn)制造的一項(xiàng)必要性指標(biāo)值，早已造成廣泛關(guān)注。羅茨鼓風(fēng)機(jī)噪聲一直是無(wú)法解決的問(wèn)題，目的是為了根據(jù)電磁感應(yīng)、機(jī)械設(shè)備、自然通風(fēng)三方面要素一同危害。對(duì)于羅茨鼓風(fēng)機(jī)噪聲的降低**的方法是：尋找噪聲形成的根本原因，或使用一些科技手段消弱羅茨鼓風(fēng)機(jī)的噪聲。下邊我就降低羅茨鼓風(fēng)機(jī)噪聲的方式，為大伙兒做一個(gè)簡(jiǎn)單介紹吧：

　　一.從聲源處下手，降低噪聲羅茨鼓風(fēng)機(jī)減噪*壓根的方法是以聲源處下手，選用一些消音器、隔音、吸音、減振等基本的降低噪聲的技術(shù)性。

　　1.降低排氣管噪聲。排氣管噪聲是發(fā)電機(jī)組*主要的噪聲源，其特點(diǎn)是噪聲級(jí)高，排氣管速度更快，整治難度大。選用精制的抗阻型復(fù)合型的消音器，一般可讓排氣管噪聲降低40-60db(a)。

　　2.降低軸流式風(fēng)機(jī)噪聲。降低發(fā)羅茨鼓風(fēng)機(jī)組冷卻風(fēng)機(jī)噪聲時(shí)，務(wù)必考慮到兩個(gè)問(wèn)題，一是排氣管安全通道所容許的壓力損失。二是規(guī)定的消音量。對(duì)于以上二點(diǎn)，可采用阻性管式消音器。

　　3.主機(jī)房的隔音、吸音解決和發(fā)電機(jī)組減振

　　(1)主機(jī)房隔音。設(shè)備的排氣管噪聲和冷卻風(fēng)機(jī)噪聲降低以后，剩下來(lái)的關(guān)鍵噪聲源是羅茨鼓風(fēng)機(jī)械噪聲。選用的方法是什么除需要的與隔離室相互連接的墻內(nèi)視窗以外，其它窗子均去除，全部孔、洞要密實(shí)度堵漏，墻體墻面的隔音性規(guī)定要40db(a)之上。計(jì)算機(jī)房窗門選用防火安全隔音窗門。

　　(2)進(jìn)風(fēng)和排風(fēng)系統(tǒng)。數(shù)據(jù)中心隔音解決以后，要處理主機(jī)房?jī)?nèi)排風(fēng)排熱難題。進(jìn)氣口應(yīng)與羅茨鼓風(fēng)機(jī)組、排風(fēng)口設(shè)定在同一平行線上。進(jìn)氣口應(yīng)配以阻性管式消音器，因?yàn)檫M(jìn)氣口壓力損失亦在允許范圍內(nèi)，能使主機(jī)房?jī)?nèi)出入排風(fēng)量當(dāng)然做到均衡，自然通風(fēng)排熱效果明顯。

　　(3)吸音解決。主機(jī)房?jī)?nèi)除路面外的五個(gè)邊界層能作吸音解決，依據(jù)羅茨鼓風(fēng)機(jī)組的頻域特點(diǎn)選用穿孔鋁板共震吸音構(gòu)造。

　　(4)室內(nèi)環(huán)境的溝通交流，主機(jī)房的優(yōu)良隔音，會(huì)讓羅茨鼓風(fēng)機(jī)組關(guān)機(jī)機(jī)會(huì)屋內(nèi)的氣體無(wú)法得到熱對(duì)流，屋內(nèi)的持續(xù)高溫亦無(wú)法立即降下去，可選用低噪聲軸流式風(fēng)機(jī)，另配上阻性管式消音器就能夠解決困難。

　　(5)發(fā)電機(jī)組減振。羅茨鼓風(fēng)機(jī)組組裝前，應(yīng)嚴(yán)苛按生產(chǎn)廠家供應(yīng)的相關(guān)材料開(kāi)展減振解決，規(guī)避導(dǎo)致構(gòu)造聲的長(zhǎng)距離散播，請(qǐng)?jiān)谏⒉ブ谐掷m(xù)輻射空氣聲，沒(méi)法使大氣污染物噪聲級(jí)合格。對(duì)因不合格而規(guī)定整治的目前羅茨鼓風(fēng)機(jī)組，需要評(píng)測(cè)發(fā)電機(jī)組周邊路面的震動(dòng)狀況，假如振感顯著，則需先對(duì)羅茨鼓風(fēng)機(jī)組開(kāi)展減振解決。

　　二.羅茨鼓風(fēng)機(jī)噪聲一直是無(wú)法解決的問(wèn)題，

　　目的是為了根據(jù)電磁感應(yīng)、機(jī)械設(shè)備、自然通風(fēng)三方面要素一同危害。在安裝羅茨鼓風(fēng)機(jī)的情況下，應(yīng)用幾類處理辦法針對(duì)抑止羅茨鼓風(fēng)機(jī)機(jī)械設(shè)備噪聲較為合理。

　　1.電機(jī)轉(zhuǎn)子軸力造成的噪聲。當(dāng)定轉(zhuǎn)子軸力時(shí)，會(huì)造成單側(cè)磁抗拉力噪聲：

　　a.電動(dòng)機(jī)軸兩邊噪聲比較大

　　b.切斷電源后立刻消退

　　c.響聲相對(duì)穩(wěn)定

　　當(dāng)發(fā)生之上狀況時(shí)，理應(yīng)各自查驗(yàn)電機(jī)轉(zhuǎn)子鐵芯相對(duì)于兩邊軸承臺(tái)的圓柱度和電動(dòng)機(jī)軸兩邊槽口相對(duì)于電機(jī)定子鐵芯的平行度。

　　(1)假如是電機(jī)轉(zhuǎn)子軸力，可根據(jù)以軸承臺(tái)為標(biāo)準(zhǔn)，重打中心孔后再光(磨)電機(jī)轉(zhuǎn)子的方法來(lái)處理

　　(2)假如是電機(jī)定子軸力，能夠電動(dòng)機(jī)軸槽口為標(biāo)準(zhǔn)車圓電機(jī)定子鐵芯公稱直徑。

　　需要注意的是：不管哪種方法，都是會(huì)擴(kuò)大磁密，這可能使功率因數(shù)減少。因而加工量需把控在0.3mm之內(nèi)。適度**磁密能夠降低諧波電流電磁場(chǎng)的幅度值，降低磁密的不勻稱度并能使徑向力波的幅度值降低，都可讓噪聲隨著降低。

　　2.軸承軸向側(cè)隙的調(diào)節(jié)。

　　軸承的軸向工作中側(cè)隙是造成軸承噪聲的主要原因，尤其是軸承軸向工作中側(cè)隙小了或無(wú)空隙運(yùn)作，噪聲超標(biāo)準(zhǔn)更加突顯。從實(shí)驗(yàn)獲知：H560-H355的軸承軸向裝配間隙(軸承孔與軸承中間)確保在0.013-0.028mm的范圍之內(nèi)，就可基本上清除無(wú)空隙或間隙小了運(yùn)作，軸承噪聲顯著降低。

　　3.改裝消聲罩。

　　目的是為了用于降低自然通風(fēng)噪聲。在大中小型羅茨鼓風(fēng)機(jī)中，消音罩通常加進(jìn)通風(fēng)管道的前面。吸音材料襯層薄厚取50-70mm，吸音材料選用塑料泡沫或者海棉，消音罩的效果明顯。

　　總的來(lái)說(shuō)，為了能降低羅茨鼓風(fēng)機(jī)噪聲，除開(kāi)從聲源處下手外，還能夠選用科學(xué)合理、**的加工工藝對(duì)策，這針對(duì)降低羅茨鼓風(fēng)機(jī)噪聲全是有益的，使羅茨鼓風(fēng)機(jī)品質(zhì)獲得確保。結(jié)合我廠售后部門的維修維護(hù)經(jīng)驗(yàn)，我們總結(jié)出了兩種短期內(nèi)有效控制羅茨鼓風(fēng)機(jī)噪音的方法！

　　有效控制羅茨鼓風(fēng)機(jī)噪聲*壓根的方法由下面二種：

　　1.羅茨風(fēng)機(jī)改裝隔聲罩

　　1)將隔聲罩進(jìn)風(fēng)口部位挪到罩體下邊，是隔聲罩內(nèi)氣旋產(chǎn)生連續(xù)流，并通過(guò)電機(jī)和離心風(fēng)機(jī)人體開(kāi)展制冷

　　2)隔聲罩進(jìn)風(fēng)口擴(kuò)大至600mm*250mm，降低進(jìn)氣口摩擦阻力減少羅茨離心風(fēng)機(jī)負(fù)載。

　　3)隔聲罩進(jìn)風(fēng)口由戶外送風(fēng)改成房間內(nèi)送風(fēng)，禁燒自然通風(fēng)摩擦阻力，改進(jìn)風(fēng)機(jī)房自然通風(fēng)情況。

　　4)風(fēng)機(jī)房?jī)?nèi)**排風(fēng)扇，將隔聲罩內(nèi)熱氣直接排放戶外，排氣扇安裝消音器;請(qǐng)?jiān)谠谄渲性O(shè)定止逆閥。

　　2.對(duì)風(fēng)機(jī)房開(kāi)展隔音降噪提高。

　　1)風(fēng)機(jī)房門改成隔音門，設(shè)計(jì)方案隔音性為30聲貝，原鋼質(zhì)門隔音性不夠10聲貝

　　2)西邊窗子改成隔聲窗，為降低成本費(fèi)在原來(lái)窗子里側(cè)改裝固定不動(dòng)窗戶，正中間做隔聲解決。

　　3)風(fēng)機(jī)房撞南墻下邊進(jìn)氣口設(shè)定消音進(jìn)箱式風(fēng)機(jī)。進(jìn)氣口合理離心風(fēng)機(jī)依據(jù)3臺(tái)羅茨離心風(fēng)機(jī)需要進(jìn)排風(fēng)量明確。

　　4)撞南墻兩部排風(fēng)扇改成低噪聲排氣管上，并裝有消音器，排風(fēng)扇為降低室內(nèi)氣溫應(yīng)用。

　　該羅茨離心風(fēng)機(jī)減噪新項(xiàng)目解決完成后，通過(guò)檢驗(yàn)，在3臺(tái)開(kāi)全很有可能較大工作狀況下，風(fēng)機(jī)房均值噪聲即將到來(lái)76聲貝，監(jiān)控室挨近風(fēng)機(jī)房噪聲即將到來(lái)62聲貝，大氣污染物噪聲即將到來(lái)47聲貝，超過(guò)我國(guó)有關(guān)自然環(huán)境噪聲規(guī)范！

　　People in the field of Roots blower should understand that noise is a necessary index value for the production and manufacture of Roots blower, which has already caused widespread concern. The noise of Roots blower has always been a problem that cannot be solved. The purpose is to do harm together according to electromagnetic induction, mechanical equipment and natural ventilation. The way to reduce the noise of Roots blower * * is to find the root cause of the noise, or use some scientific and technological means to weaken the noise of Roots blower. Next, I'll give you a brief introduction on how to reduce the noise of Roots blower:

　　I Starting from the sound source, the most fundamental way to reduce the noise of Roots blower is to start from the sound source, and select some basic noise reduction techniques such as muffler, sound insulation, sound absorption, vibration reduction, etc.

　　1. Reduce the noise of exhaust pipe. Exhaust pipe noise is the main noise source of generator set, which is characterized by high noise level, faster exhaust pipe speed and great difficulty in remediation. The noise of the exhaust pipe can generally be reduced by 40-60db (a) by selecting a refined resistance composite muffler.

　　2. Reduce the noise of axial flow fan. When reducing the noise of the cooling fan of the roots blower unit, two problems must be considered: one is the allowable pressure loss of the safety channel of the exhaust pipe. The second is the specified volume reduction. For the above two points, the resistive pipe silencer can be used.

　　3. Sound insulation and absorption of main engine room and vibration reduction of generator set

　　(1) Sound insulation of main engine room. After the exhaust pipe noise and cooling fan noise of the equipment are reduced, the remaining key noise source is roots blower machinery noise. What is the method selected? Except for the window in the wall that needs to be connected with the isolation room, other windows should be removed, all holes and holes should be sealed with compactness, and the sound insulation of the wall should be above 40dB (a). The windows and doors of the computer room shall be fireproof, safe and sound proof.

　　(2) Air intake and exhaust system. After the sound insulation of the data center is solved, the problem of air and heat exhaust in the host room should be solved. The air inlet shall be set on the same parallel line with roots blower unit and exhaust outlet. The air inlet should be equipped with a resistive pipe muffler, because the pressure loss of the air inlet is also within the allowable range, which can naturally balance the air volume in and out of the main engine room, and the natural ventilation and heat removal effect is obvious.

　　(3) Sound absorption solution. The five boundary layers in the main engine room except the road surface can be used for sound absorption. According to the frequency domain characteristics of Roots blower unit, perforated aluminum plate co vibration sound absorption structure is selected.

　　(4) The communication of the indoor environment and the excellent sound insulation of the main engine room will make the roots blower unit shut down. The gas in the house cannot get thermal convection, and the continuous high temperature in the house cannot be reduced immediately. You can choose a low-noise axial-flow fan and add a resistive pipe muffler to solve the problem.

　　(5) Vibration reduction of generator set. Before the assembly of Roots blower unit, the vibration reduction solution should be strictly carried out according to the relevant materials supplied by the manufacturer to avoid the long-distance spread of structural sound. Please continue to radiate air sound in the spread, which cannot make the noise level of air pollutants qualified. For the current roots blower units that are required to be rectified due to disqualification, it is necessary to evaluate the vibration condition of the road around the generator unit. If the vibration is significant, it is necessary to carry out vibration reduction for Roots blower units first.

　　II The noise of Roots blower has always been an unsolvable problem,

　　The purpose is to do harm together according to electromagnetic induction, mechanical equipment and natural ventilation. In the case of installing roots blower, it is reasonable to apply several kinds of treatment methods to suppress the noise of Roots blower mechanical equipment.

　　1. Noise caused by motor rotor axial force. When the stator and rotor shaft force, it will cause unilateral magnetic anti tension noise:

　　a. The noise on both sides of the motor shaft is relatively large

　　b. Immediately fade after cutting off the power supply

　　c. The sound is relatively stable

　　When the above situation occurs, it is necessary to check the cylindricity of the motor rotor core relative to the bearing platforms on both sides of the shaft and the parallelism of the slots on both sides of the motor shaft relative to the motor stator core.

　　(1) If it is the axial force of the motor rotor, it can be handled according to the method of taking the bearing platform as the standard, re punching the center hole and then polishing (grinding) the motor rotor

　　(2) If it is the axial force of motor stator, the slot of motor shaft can be the nominal diameter of stator core of standard turning motor.

　　It should be noted that either method will expand the magnetic density, which may reduce the power factor. Therefore, the processing volume should be controlled within 0.3mm. Moderately increasing the magnetic density can reduce the amplitude value of harmonic current electromagnetic field, reduce the asymmetry of magnetic density and reduce the amplitude value of radial force wave, which can reduce the noise.

　　2. Adjustment of axial clearance of bearing.

　　The side clearance of bearing in axial operation is the main cause of bearing noise, especially when the side clearance of bearing in axial operation is small or there is no clearance, the noise exceeding the standard is more prominent. It is learned from the experiment that the axial assembly clearance (between the bearing hole and the bearing) of the bearing of h560-h355 is ensured to be within the range of 0.013-0.028mm, which can basically eliminate the operation without clearance or with small clearance, and the bearing noise is significantly reduced.

　　3. Refit the muffler.

　　The purpose is to reduce the noise of natural ventilation. In large, medium and small roots blowers, the muffler is usually added in front of the ventilation duct. The thickness of the sound-absorbing material lining is 50-70mm. The sound-absorbing material is plastic foam or sponge, and the effect of the muffler is obvious.

　　In general, in order to reduce the noise of Roots blower, in addition to starting from the sound source, scientific, reasonable and excellent processing technology countermeasures can also be selected, which is beneficial to reduce the noise of Roots blower and ensure the quality of Roots blower.

　　There are two ways to effectively control the noise of Roots blower:

　　1. Refit the sound insulation cover of roots centrifugal fan

　　1) Move the air inlet of the sound insulation cover to the lower side of the cover, because the cyclone in the sound insulation cover generates continuous flow, and refrigeration is carried out by the motor and centrifugal fan

　　2) The air inlet of the acoustic enclosure is expanded to 600mm*250mm to reduce the friction resistance of the air inlet and reduce the load of roots centrifugal fan.

　　3) The air inlet of the acoustic enclosure is changed from outdoor air supply to indoor air supply, and the friction resistance of natural ventilation is prohibited, so as to improve the natural ventilation of the fan room.

　　4) The exhaust fan is lifted in the fan room to directly discharge the hot gas in the sound insulation hood outdoors, and the exhaust fan is installed with a silencer; Please set the check valve in it.

　　2. Improve the sound insulation and noise reduction of the fan room.

　　1) The fan room door is changed into a sound proof door. The sound insulation of the design scheme is 30 sound shells, and the sound insulation of the original steel door is not enough to 10 sound shells

　　2) The west window is changed into a sound insulation window. In order to reduce the cost, the fixed window is refitted on the inner side of the original window, and the sound insulation is done in the middle.

　　3) The silencing box type fan is set at the air inlet under the south wall of the fan room. The reasonable air inlet of centrifugal fan is determined according to the inlet and exhaust air volume of three roots centrifugal fans.

　　4) The two exhaust fans on the south wall are changed into low-noise exhaust pipes and equipped with silencers. The exhaust fans are used to reduce indoor temperature.

　　After the completion of the new project of noise reduction of roots centrifugal fans, the inspection showed that under the working condition that the three fans are likely to be fully opened, the average noise of the fan room is about to reach 76 sound decibels, the noise of the monitoring room close to the fan room is about to reach 62 sound decibels, and the noise of air pollutants is about to reach 47 sound decibels, exceeding the relevant natural environmental noise norms of our country!