Hydraulic Formulas for Motors and Pumps

Hydraulic Formulas for Motors and Pumps: Essential Calculations for Optimal Performance

Although motors and pumps may appear similar, they serve distinct functions in hydraulic systems. Pumps utilise an external power source, such as an engine or electric motor, to create flow within a hydraulic system. In contrast, a hydraulic motor produces rotational force when fluid passes through it. 

Key Differences Between Hydraulic Motors and Pumps

Purpose and Energy Conversion

• Hydraulic pumps convert mechanical energy into hydraulic pressure energy
• Hydraulic motors convert hydraulic energy into mechanical energy for rotary motion

Below are some formulas you can use to calculate important figures when working with hydraulic pumps and motors.

Here are the essential hydraulic formulas for motors & pumps to help calculate performance metrics like displacement, torque, speed, and power in hydraulic motor systems.

1. Displacement (cm³/rev or cc/rev)

• D = Displacement (cm³/rev)
• Q = Flow rate (L/min)
• N = Motor speed (rpm)

2. Motor Speed (rpm)

• N = Speed (rpm)
• Q = Flow rate (L/min)
• D = Displacement (cm³/rev)

3. Torque (Nm)

• T = Torque (Nm)
• D = Displacement (cm³/rev)
• ΔP = Pressure drop across motor (bar)

4. Hydraulic Power (kW)

• P = Power (kW)
• T = Torque (Nm)
• N = Speed (rpm)

5. Power (Hydraulics)

6. Flow Rate (L/min)

• Q = Flow rate (L/min)
• D = Displacement (cm³/rev)
• N = Speed (rpm)

Leading UK Provider of Hydraulic System Components and Accessories: Flowfit

Flowfit are your go-to source for top-of-the-line hydraulic system components and accessories. Our company prides itself on delivering quality products that surpass industry standards. If you're unsure about what you need or can't seem to find a specific product, don't hesitate to give us a call. Our Technical Sales team is well-versed in the latest industry trends and can suggest the best products for your needs. 

For further details, get in touch with our team of hydraulic specialists today!