三螺杆泵功率计算

三螺杆泵的轴功率一般为水功率、摩擦功率和泄漏损失功率这三部分的总和。水功率Nc是指单位时间内泵传给液体的能量，也称输出功率，可用下式计算：  式中：P—泵的排出压力和吸入压力之差，帕；Q—泵的实 际排量，m3/s。 摩擦功率是指液体粘性阻力产生的摩擦损失，可由下式表示：The pump shaft power is commonly water power and leakage, friction power loss power that the sum of three parts.Water power Nc is refers to the pump to the energy of the fluid, also known as output power, calculate the type:Type: P - the difference between the pump discharge pressure and suction pressure, palmer.Q - the actual displacement of the pump, m3 / s.      Friction power refers to the friction loss, the liquid viscous resistance, can be represented by the type:                                                              

式中：n—转速；D—主动螺杆的外径； —粘度；K—与螺杆长度有关的系数；m是与流量Q有关的系数。由上可见，当泵运送的液体粘度不同时，泵的轴功率也将不同。当旁通阀开启时，液体是在有节流的情况下在泵中不断循环流动的，而循环的油量越多，循环的时间越长，液体的发热也就越严重，甚至使泵因高温变形而损坏，   引起注意。泄漏损失是指液体从高压处漏回低压处所造成的功率损失。螺杆泵应在吸排停止阀全开的情况下起动，以防过载或吸空。螺杆泵因工作螺杆长度较大，刚性较差，容易引起弯曲，造成工作失常。对轴系的连接   很好对中；对中工作   好是在安装定位后进行，以免管路牵连造成变形；连接管路时应独立固定，尽可能减少对泵的牵连等。此外，备用螺杆，在保存时   好采用悬吊固定的方法，避免因放置不平而造成的变形。 螺杆泵虽然具有干吸能力，但是   防止干转，以免擦伤工作表面。 Type: n - speed;D - active screw diameter;- viscosity;K - factor related to the length of screw;M is related to the flow rate Q factor.By visible, when the pump transporting liquid viscosity is not at the same time, the pump shaft power will also be different.When the bypass valve opens, the liquid is in the case of a throttle cycle flow in the pump, and the cycle of oil, the more the longer cycle, the liquid fever also becomes more serious, even make pump due to the high temperature deformation and damage, must pay attention.Leakage loss is refers to the liquid leakage from high pressure to low pressure place of power loss.Screw pump should be in suction stop valve fully open under the condition of starting, in case of overload or empty.Screw pump screw length is larger because of the job, poor rigidity, easy to cause bending work properly.For shaft connection must be very good for;To work in the best is the installation location, lest cause deformation of pipeline in;When connecting line shall be independent of fixed, as far as possible to reduce the involvement of the pump, etc.In addition, the spare screw, had better use the method of suspension fixed when save, avoid caused by placing uneven deformation.Screw pump have dry absorption ability, but have to turn, prevent dry to avoid surface scratch work

假如三螺杆泵需要在油温很低或粘度很高的情况下起动，应在吸排阀和旁通阀全开的情况下起动，让泵起动时的负荷   低，直到原动机达到额定转速时，再将旁通阀逐渐关闭。.If the pump need to be in the oil temperature is low or high viscosity under the condition of starting, suction exhaust valve and bypass valve should be fully open under the condition of starting, let the minimum load when the pump starts, until the prime mover to the rated speed, then bypass valve shut down gradually.