How to choose hyd motor


As one of the executive components of the hydraulic system, the hydraulic motor is used to convert the pressure energy of the liquid into mechanical energy to drive the machine parts to work. It is a hydraulic device that drives the rotation of the equipment parts. There are many kinds of hydraulic motors on the market, so how should we choose when we buy hydraulic motors?


In fact, when purchasing a hydraulic motor, the most important thing is to figure out the following 4 technical indicators.


1. Flow

①The hydraulic oil is injected into the hydraulic motor. The injected hydraulic oil is measured by "flow rate", that is, the volume of hydraulic oil injected into the motor in one minute, and the unit is "L/min".

②After the hydraulic oil is injected into the motor, it must flow out. Otherwise, all the hydraulic oil will accumulate in the motor, which will cause an explosion. In theory, the flow rate of the hydraulic oil injected into the motor is equal to the flow rate out of the hydraulic motor.

③The flow rate is related to the speed of the motor output shaft, and they are in direct proportion. At this time, we have obtained another invisible parameter of the motor called displacement, that is, the hydraulic pressure injected or discharged when the motor rotates for one revolution. Oil volume in "ml/r".

④The size of the hydraulic motor is measured by the displacement, so the size of the motor refers to the displacement.

⑤ The flow of the hydraulic motor can be measured by a flow meter. Almost every hydraulic system will be equipped with a flow meter to monitor the flow change of the hydraulic system at any time.


2. Pressure

①After the hydraulic oil is injected, it is necessary to drive the motor to rotate, so the hydraulic oil needs to have a certain pressure, that is, a force is required to drive the hydraulic motor to rotate. This driving force is the pressure, and their unit is not "N", but "MPa" , which is a unit of pressure, but pressure is usually referred to as pressure in hydraulics.

②The size of the hydraulic motor pressure is determined by the load, not generated by the motor.

③The rated pressure of the motor refers to the allowable pressure value when the motor runs continuously.

④The pressure is measured by the pressure gauge. The range of the pressure gauge is selected according to the maximum pressure of the hydraulic system. It is better to reserve several pressure gauge interfaces when designing the hydraulic system, so as to monitor the pressure change of the system at any time.


3. Speed

①The rotational speed of the hydraulic motor is a parameter to measure the rotation speed of the motor output shaft, which is generally determined by the customer according to the operating speed of the equipment.

②The classification of hydraulic motors is defined according to the rotational speed, which is divided into high-speed motors and low-speed motors. Generally speaking, high-speed motors have a speed of more than 500 rpm, and low-speed motors have a speed of less than 500 rpm.

③Hydraulic motors generally have a minimum stable speed. Below this value, the motor will crawl.


4. Torque

①The output shaft of the motor is to drive the mechanical parts to rotate. Therefore, the motor must have a certain driving force to drive the mechanical parts. So what are the parameters for measuring the driving force of the motor? "Torque", the unit is "Nm" , is the force acting on a moment arm of a certain length.

②The amount of torque of the motor is determined by the load. How much torque is required to drive the load will be provided by the motor. If the torque required by the load is too large, the motor will not be able to carry the load. It is said to be overloaded.

③The measurement of torque is measured with a torque meter.


For a hydraulic motor, the energy generated by the hydraulic oil injected into the hydraulic motor is theoretically equal to the energy generated by the motor output shaft. This is the energy conservation of the motor, that is, the input and output power of the motor is equal. It can be expressed by the following formula: P hydraulic oil = P output shaft.


a. Power of hydraulic oil = flow X pressure


b. Power of output shaft = torque X angular velocity


c. Flow X pressure = torque X angular velocity


After calculation, it is obtained: flow X pressure = torque X2πX speed


From the above formula, as long as any three parameters are known, the size of the other parameter can be obtained. The selection of the motor is calculated by this formula.


When purchasing a motor, you need to choose a product with suitable flow rate, speed, torque and pressure according to your actual needs. My suggestion is that you can directly tell the customer service about your needs, and let the customer service recommend several hydraulic motors according to your actual needs. The customer service of Hanjiu Technology Co., Ltd. will answer all your questions carefully. Hanjiu's goal is to allow every customer to buy the products they like at Hanjiu and get the best service experience.


Hanjiu Technology is a professional hydraulic product manufacturing company. Since 2010, it has been the first factory in northern China to produce and export hydraulic rail motors and steering gears. Hanjiu has accumulated rich experience in the production of hydraulic motors. You can basically find all hydraulic motor models on the market in Hanjiu; three professional production lines and a large factory site of nearly 1,0000 square meters ensure that Hanjiu's products can be A large amount of output is stably produced every year; strict multiple pre-delivery inspections ensure product quality, and Hanjiu can ensure that the quality of all products that leave the factory is uniform, and there are no inferior products mixed in.


The hydraulic motors produced by Hanjiu are very cost-effective. If you are interested in this, please come to Hanjiu's official website!


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