Types of Linear Actuators: Electric, Hydraulic, Pneumatic, Servo, Stepper & Belt Driven
Linear actuators come in several types: electric, hydraulic, pneumatic, servo, stepper motor and belt driven. This guide explains how each works and when to choose it. Purlin Automation makes electric mechanical linear actuators in Bengaluru, India.
Linear actuator types compared
| Type | How it works | Strengths | Limits | Typical use |
|---|---|---|---|---|
| Electric mechanical (screw driven) | DC motor, gearbox and lead screw | Clean, quiet, easy to control, only needs a power supply | Speed and force are traded off | Furniture, medical beds, automation. Purlin range |
| Rod type (tubular) | Rod extends from a tube | Compact, simple to mount, push and pull | Stroke fixed by the tube length | Lifting, tilting, positioning |
| Stepper motor | Motor moves in fixed steps | Repeatable positioning, often without feedback | Can lose steps under overload | Light-load positioning |
| Servo | Motor with encoder, closed loop | Precise position and speed control | Higher cost and a drive is needed | Precision automation |
| Belt driven | Toothed belt moves a carriage on a rail | Long strokes, high speed | Lower force than screw drive | Gantries, long travel |
| Hydraulic | Pressurised fluid and pump | Very high force | Pump, hoses and leak risk, more maintenance | Heavy machinery |
| Pneumatic | Compressed air | Fast and simple | Needs a compressor, harder to position precisely | Fast pick-and-place, clamping |
Electric linear actuators
Electric actuators are the most common choice for equipment that must be clean, quiet and simple to control. A DC motor turns a lead screw, and a nut moves the rod in and out. Our electric linear actuators are electric mechanical actuators with inbuilt limit switches and IP54 protection. Ask us for the technical drawing to confirm the mounting style.
Hydraulic and pneumatic linear actuators
Hydraulic linear actuators produce very high force but need a pump, hoses and fluid, and they can leak. Pneumatic linear actuators are fast and low cost but need a compressor, and air is compressible so stopping at exact mid-stroke positions is difficult. Many applications that once used hydraulic or pneumatic cylinders now use an electric actuator instead because it needs only a cable.
Servo and stepper motor linear actuators
Servo linear actuators and stepper motor linear actuators are chosen when you need to control position exactly. They need a drive or controller. If you only need to move between two end positions, a DC electric actuator with limit switches is simpler. Tell us if you need position feedback and we will discuss the options.
Belt driven and rod type tubular linear actuators
A belt driven linear actuator suits long, fast travel with lighter loads. A rod type tubular linear actuator is the better choice for pushing, pulling and lifting heavier loads over a defined stroke.
12VDC, 24VDC, mini and micro linear actuators
Pick the voltage your power supply gives. 24VDC draws half the current of 12VDC at the same power. Our common configurations are 12VDC and 24VDC; the models listed here are 24VDC. For small mechanisms, mini and micro linear actuators with a short stroke are available in the PAI-02, PAI-16 and PAI-36 series (50mm to 200mm, 300mm or 400mm). See the selection guide for every model by force, speed and stroke.
Frequently asked questions
What is the difference between electric, hydraulic and pneumatic linear actuators?
Electric actuators use a motor and screw and need only electrical power. Hydraulic actuators use pressurised fluid and a pump, and are used for very large forces. Pneumatic actuators use compressed air and are fast and simple but harder to position precisely. Electric actuators are the cleanest and easiest to control.
What is a rod type (tubular) linear actuator?
A rod type or tubular linear actuator has a rod that extends from and retracts into a tube. It is the usual form of electric linear actuator for pushing, pulling and lifting loads, with a clevis or bracket at each end.
What is the difference between stepper motor and servo linear actuators?
A stepper motor linear actuator moves in fixed steps and is often run without position feedback. A servo linear actuator uses an encoder for closed-loop control, giving more precise positioning at a higher cost. Basic DC linear actuators with limit switches are the simplest and lowest-cost option.
What is a belt driven linear actuator?
A belt driven linear actuator moves a carriage along a rail with a toothed belt. It suits long strokes and high speeds with lighter loads. Screw-driven rod actuators give higher force.
Should I choose a 12VDC or a 24VDC linear actuator?
Choose the voltage your power source supplies. At the same power a 24V actuator draws half the current of a 12V one. Our common configurations are 12VDC and 24VDC; the models listed on this site are 24VDC, so contact us if you need 12VDC.
Does Purlin Automation make hydraulic or pneumatic actuators?
Our catalogue is electric linear actuators. If your machine uses a hydraulic or pneumatic cylinder today, send us the force, stroke and speed and we will advise whether an electric actuator can replace it.
Need help choosing a linear actuator?
Send your load (N), speed (mm/sec), stroke length (mm), voltage and application. Our Bengaluru team will recommend the right model and send a quotation.
Request a quotation