Consider choosing the suitable electric pump motor for your forklift hydraulic system from our wide catalog.
Forklift electric pump motor
Reading time:3 min 24 sec
Forklifts have a hydraulic system compounded by a pump, a cylinder, and an electric pump motor. This system drives fluid into the cylinder and allows the forklift to move the fork upwards. This device produces a rotational force that is applied to the pump.
Figure 1. Electric pump motor
Electrical pump motor parts
Stator: It is the fixed part of a motor. It is made of magnetic material and electrical conductors (positive and negative) to generate a magnetic field.
Rotor: It is the moving part of the motor. It consists of a cylinder with electro-magnets poles facing toward the stator poles. Usually, its location is inside the stator.
Shaft: It is a rotating part that transmits the mechanical energy to the pump.
Bearing: This piece separates the shaft from the parts that are attached to it. The bearing reduces motor noise level and improves shaft precision.
Housing: This part protects the internal motor components from dirt and other damages.
Figure 2. Electric pump motor parts
How an electrical pump motor work
The electric motor operation is based on the below laws:
Ampere's law says that when an electric current travels through a wire, a magnetic field is created around it.
Faraday's law states that a conductor moves perpendicular within a magnetic field.
When the electrical pump motor runs, an electromagnetic field is created between the stator and the rotor. Once the electricity goes through the wire, the polarity of rotor sides and stator sides are different.
This rotor spins to align its poles with the magnetic field. The polarity is continuously reversed for keeping the rotation. It means that positive poles change to negative, and vice versa.
Electrical pump motor types
Alternating current motor (AC): It changes the flow of electricity many times every second. This motor type requires an inverter to convert the current from DC to AC.
Direct current motor (DC): This motor works with a simplified circuit. It obtains its energy from a battery and a switch that alternates the current direction.
Electric forklifts are powered with AC and DC using VDC batteries. The DC Motors allow a forklift to run from 96 to 192 volts. There are four main DC motor types:
Permanent magnet ( PMDC).
The most commonly used for forklifts are the PMDC and wound field types. On the other hand, AC motors can be :
The forklifts use three-phase AC motors that allow 240V operation.
How to choose a correct electrical pump motor
Nameplate: It is a metallic plate that has all the technical specifications of your electrical pump motor, for example:
Number of phases
Figure 3. Example of a nameplate
An AC motor generates most of the heat in the stator windings that dissipates quickly. It avoids electric pump motor damage. Generally, this motor type is stronger than a DC motor. Among DC motors, the permanent magnet has more thermal resistance than the wound field type. For this reason, PMDC is preferable in continuous operations and the wound field for intermittent operations.
Given that the AC motors do not have brushes and commutators, it does not require much maintenance. On the other hand, the DC motors have these parts that periodically are worn out and need replacement.
Forklift battery life
The battery on an AC motor-powered forklift can last longer than one using a DC motor. IT happens given that the AC motor works as an energy regenerator (using the braking system). It recharges the batteries while current flows from the DC battery to the AC motor and vice versa through the inverter.
An AC motor is the more suitable option for integrated systems (lift and steering). The DC motors are also used for forklifts for small steering and forklift systems (permanent magnet DC motor) and system with constant pump speed (wound DC motor).
The motor stops running or runs poorly for different reasons:
Short circuits in the coil, connections, or between phases: A short circuit is the most known problem of an electrical pump motor. It can be caused by:
metal elements that accidentally join the contacts.
Cables broken or badly damaged.
The lack of insulating varnish of the conductors.
Humidity, dust, and water leaks.
Motor overload: It occurs when the motor works with a load greater than the maximum allowed. Another factor that could cause this problem is a stuck motor shaft. The leading cause of motor failure is a temperature rise. It causes premature wear of the motor and its internal parts.
Supply voltage: This problem usually occurs when the line voltage is different in each phase, and the motor heats up. It directly affects the insulation system and the lubrication of the bearings.
To request more information about our Forklift electric pump motor, do not hesitate to contact our specialists. We help you to find the correct one for your forklift. Our products ship from multiple shipping locations and come with a 1-year limited warranty.