(2)改變轉(zhuǎn)速的方法：改變皮帶輪外徑或改變齒輪減速器傳動(dòng)比，也可選用不同轉(zhuǎn)速的動(dòng)力機(jī)。jdhuiquan717

(3)水泵轉(zhuǎn)速改變后，其流量(Q)、揚(yáng)程(H)和功率(N)的變化關(guān)系如下式所示： Q1=Q*n1/n   H1=H*(n1/n)2    N1=N*(n1/n)3

 式中：Q1、H1、N．分別代表轉(zhuǎn)速改變后的流量、揚(yáng)程和功率。 Q、H、N分別代表規(guī)定轉(zhuǎn)速下的流量、揚(yáng)程和功率。

(4)水泵轉(zhuǎn)速提高后，耗用功率增加，吸上真空度降低，壽命縮短。過(guò)分提高轉(zhuǎn)速會(huì)發(fā)生其它事故，故應(yīng)慎用。

(5)水泵轉(zhuǎn)速過(guò)分降低時(shí)，泵的使用效益低，為此，應(yīng)盡量避免泵在過(guò)低轉(zhuǎn)速下運(yùn)行。用戶(hù)應(yīng)按性能曲線圖選擇使用。

大型混流泵A贊皇大型混流泵300HW-5

The output shaft is connected at the top of the guanting, which can drive the generator to generate electricity or drive other machinery such as agricultural and sideline products processing machinery.

2、允許吸上真空度[Hs]與必需汽蝕余量[NPSH]r的換算關(guān)系：

 [Hs]≈10-[HPSH]c

 [NPSH]r≈[NPSH]C+0.3

 式中：[Hs]-允許吸上真空度   米

 [NPSH]C-臨界汽蝕余量   米

 [NPSH]r-必需汽蝕余量   米

 *特征描述

HW 型蝸殼式混流泵是按國(guó)家標(biāo)準(zhǔn)最新系列而設(shè)計(jì)的高節(jié)能產(chǎn)品。其性能指標(biāo)均達(dá)到國(guó)際先進(jìn)水平，省材節(jié)能效果顯著。延伸搜索：水環(huán)真空泵

（一）用途
HW型混流泵為臥式、單級(jí)、單吸、懸臂蝸殼式混流泵，適用于農(nóng)田排灌、工業(yè)、城鎮(zhèn)給排水及船塢、碼頭引水等。延伸搜索：水環(huán)真空泵
（二）特點(diǎn)
體積小、重量輕、流量大、效率高，汽蝕性能好，高效區(qū)范圍寬廣而平坦，結(jié)構(gòu)簡(jiǎn)單，使用管理方法，維修容易。延伸搜索：水環(huán)真空泵
（三）型號(hào)說(shuō)明
以250HW—8為例：
250—泵進(jìn)（出）水口直徑為250毫米。
8—泵總揚(yáng)長(zhǎng)為8米。

（四）水泵的傳動(dòng)方式
我廠生產(chǎn)的HW型系列混流泵均機(jī)（電）兩用，其轉(zhuǎn)動(dòng)方式視各地區(qū)動(dòng)力情況而定，訂貨時(shí)根據(jù)原動(dòng)機(jī)的型號(hào)（功率、轉(zhuǎn)速）確定水泵的傳動(dòng)方式，以定皮帶輪的大小或聯(lián)軸器的規(guī)格。延伸搜索：水環(huán)真空泵
（五）水泵轉(zhuǎn)向：
從水泵進(jìn)水口看葉輪為逆時(shí)針?lè)较蛐D(zhuǎn)（即箭頭所示的方向旋轉(zhuǎn)）。

大型混流泵A贊皇大型混流泵300HW-5

共有84種產(chǎn)品，分3個(gè)派生系列，413個(gè)規(guī)格型號(hào)。（1）性能范圍泵口徑50～200毫米，流量12.5～400立方米/時(shí)，揚(yáng)程8～125米，配力有柴油機(jī)直聯(lián)、皮帶傳動(dòng)，電動(dòng)機(jī)直聯(lián)，功率1.1～110千瓦，轉(zhuǎn)速1450～2900轉(zhuǎn)/分。（2）結(jié)構(gòu)型式輕小型離心泵為軸向單級(jí)單吸懸架式離心泵，泵體后開(kāi)門(mén)，出口位于中心向上，后蓋為壓嵌式，軸承體與泵體直接聯(lián)結(jié)，泵腳位于泵體下方，軸承用黃油潤(rùn)滑，軸封分為軟填料、機(jī)械密封、橡膠油封三種。葉輪均為閉式，傳動(dòng)分為聯(lián)軸器傳動(dòng)和皮帶傳動(dòng)兩種。泵葉輪轉(zhuǎn)向：從泵進(jìn)口方向看。葉輪轉(zhuǎn)向?yàn)轫槙r(shí)針，當(dāng)泵與柴油機(jī)直聯(lián)傳動(dòng)時(shí)，為逆時(shí)針。泵出口可裝置手動(dòng)泵，可去掉底閥，減少水力損失，并能使泵自吸。

Instructions for use (i) the HW mixed-flow pump is composed of main parts such as pump body, pump cover, impeller, pump shaft and bearing body. (Ii) The pump cover is a part of the pump connected to the inlet pipe, with a specified axial end gap between the end surface and the impeller (maintaining the specified axial bance after eliminating the axial activity gap of the bearing). The gap is too small to produce friction, too large will lead to the pump pressure water reflux, so that the pump efficiency is reduced, through the increase or decrease adjustment paper pad to meet the required requirements of the gap. Extended search: Water ring Vacuum Pump (iii) The sealing device is composed of a filler letter, a water seal letter, a filler cover and a lead powder (or oil immersion) asbestos root. Its role is: 1, in the tea to prevent air inhalation pump, play a sealing role. 2. When pumping, prevent water from flowing out of the pump too much along the shaft. (Iv) Shaft application to protect the shaft does not make it directly friction with the filler, if long-term use found that the bushing wear too much, can change the bushing. (V) The two supports of the pump shaft are bearings in the bearing body, and the bearing has an appropriate amount of grease in its body to lubricate the bearings. (Vi) The baffle on the shaft prevents water from flowing into the bearing body along the pump, thus protecting the bearing and extending its service life.