(2)改变转速的方法：改变皮带轮外径或改变齿轮减速器传动比，也可选用不同转速的动力机。

(3)水泵转速改变后，其流量(Q)、扬程(H)和功率(N)的变化关系如下式所示： Q1=Q*n1/n   H1=H*(n1/n)2    N1=N*(n1/n)3

 式中：Q1、H1、N．分别代表转速改变后的流量、扬程和功率。 Q、H、N分别代表规定转速下的流量、扬程和功率。

(4)水泵转速提高后，耗用功率增加，吸上真空度降低，寿命缩短。过分提高转速会发生其它事故，故应慎用。

(5)水泵转速过分降低时，泵的使用效益低，为此，应尽量避免泵在过低转速下运行。用户应按性能曲线图选择使用。

蜗壳式混流泵@阿勒泰市蜗壳式混流泵@300HW-4蜗壳式混流泵会泉可靠商家

有条件的话将混流泵的重点部位涂上黄油，在轴承内加上润滑油，以防零部件锈蚀。另外，如果长时间不使用混流泵，实际上会对其造成一定损害，这可能导致零部件锈蚀，从而水泵的使用寿命减短。

2、允许吸上真空度[Hs]与必需汽蚀余量[NPSH]r的换算关系：

 [Hs]≈10-[HPSH]c

 [NPSH]r≈[NPSH]C+0.3

 式中：[Hs]-允许吸上真空度   米

 [NPSH]C-临界汽蚀余量   米

 [NPSH]r-必需汽蚀余量   米

蜗壳式混流泵@阿勒泰市蜗壳式混流泵@300HW-4蜗壳式混流泵会泉可靠商家

 *特征描述

HW 型蜗壳式混流泵是按国家标准系列而设计的高节能产品。其性能指标均达到先进水平，省材节能效果显着。延伸搜索：水环真空泵

（一）用途
HW型混流泵为卧式、单级、单吸、悬臂蜗壳式混流泵，适用于农田排灌、工业、城镇给排水及船坞、码头引水等。延伸搜索：水环真空泵
（二）特点
体积小、重量轻、流量大、效率高，汽蚀性能好，区范围宽广而平坦，结构简单，使用管理方法，维修容易。延伸搜索：水环真空泵
（三）型号说明
以250HW—8为例：
250—泵进（出）水口直径为250毫米。
8—泵总扬长为8米。

（四）水泵的传动方式
我厂生产的HW型系列混流泵均机（电）两用，其转动方式视各地区动力情况而定，订货时根据原动机的型号（功率、转速）确定水泵的传动方式，以定皮带轮的大小或联轴器的规格。延伸搜索：水环真空泵
（五）水泵转向：
从水泵进水口看叶轮为逆时针方向旋转（即箭头所示的方向旋转）。

蜗壳式混流泵@阿勒泰市蜗壳式混流泵@300HW-4蜗壳式混流泵会泉可靠商家

泵不排液要素及处理办法如下：1，灌泵缺乏（或泵内气体未排完）。处理办法：从头灌泵。泵转向不对。处理办法：查看旋转方向。泵转速太低。处理办法：查看转速，进步转速。滤网阻塞，底阀不灵。处理办法：查看滤网，消除杂物。吸上高度太高，或吸液槽呈现真空。处理办法：减低吸上高度；查看吸液槽压力。

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 clearance 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.