Our thermal actuators are available in a variety of sizes and configurations, Vernatherm's thermal actuators may be applied in a variety of different applications because our sizes range from miniature to large & heavy duty units. Whatever the size, these fast acting self-actuating thermal actuators, produce high forces, and long travel distances, enabling the effective control of your system without the need for any electrical power.

Our thermal expansion material blend gives us an edge over our competitor's standard operating temperatures. When a customer chooses Rostra's thermal actuators, the customer is in complete control of what temperature range they receive. They can choose any temperature range from 30F to 300F which is the largest selection available today.

The diagram on the right shows a change in temperature that causes the thermal sensitive material to expand and contract. When the thermal actuator is expanding it applies pressure to the rubber plug which is forced into reduced diameters in the piston guide to achieve mechanical advantage. This extruding action pushes the piston which causes movement, or what we call "motion".

The expansion/contraction of these thermal actuators can be utilized to operate a valve, mechanical linkage, electric switch, or any other device. The plug and diaphragm type are proven to be the most reliable style for any application.

The graphed curve on the left shows a typical thermal actuator expansion curve. An expansion curve graphically displays an actuator's performance characteristics.

Typical characteristics of a performance curve are:

• Temperature Range
• Working Stroke
• Power Stroke
• Return Stroke

Rostra Vernatherm has the capability to customize your actuator's characteristics to any value you need it to be, all you need to do is provide us with the items listed above.

If you are unsure of what you need exactly, we can work with you to solve your problems and provide samples for you to test. Due to the nature of our products each thermal actuator is custom manufactured for each customer due to their individual temperature function needs.

We typically machine our thermal actuators out of brass and have them coated per our customers specifications, although machining other materials such as aluminum, and stainless steel is possible.

These thermal actuators can be machined with any type of thread, valve end, or any other custom modification you would like.

Actuator Technical Data