Thermal Actuators

	Thermal actuators allow heat energy to transform into mechanical energy through the movement of a piston. The actuator is filled with wax that changes from a solid to a liquid when heated, creating expansion. The force created is transmitted to a piston to perform the working stroke. Thermal actuators are being used in a variety of thermostatic applications. Typical applications incorporate automotive controls, aerospace, marine, and commercial heating controls.
	Our thermal actuators are calibrated for a 10 degree temperature span and are applied to provide an ideal proportional range that is adjustable within the span.
	Performance Curves Shown in the chart on the left is a typical performance curve for a thermal actuator. The majority of the actuator's power stroke is achieved between a predetermined range of temperatures. This curve can be modified to accomodate different temperature and stroke requirements. The return stroke depicts the performance as the actuator cools. The difference between the power and return stroke curves describes a typical hysteresis loop which is inherent to thermal actuators of the squeeze-push and diaphragm designs. Through skilled design techniques and material selection, we are able to maintain the smallest hysteresis loops possible. Room temperature control span is adjusted by turning the actuator in or out in a threaded thermal isolation mounting. The wax type thermal thermostatic actuator is primarily a single function control device.