In our last post, Tim Gainer, Richards Industries Regional Sales Manager, presented a case for mechanical temperature control. Let’s take a look at some applications for temperature regulators.
AIR DRYING PRODUCT
There are a variety of products that must be dried prior to use. These include but are not limited to lumber, tobacco, hops, tea and herbs. The drawing below illustrates air drying product using a mechanical temperature regulator with a “finned” sensing bulb. A finned bulb is designed for sensing the temperature of the atmosphere. The fins increase the effective exposed surface area, providing the necessary sensitivity. It is used effectively in air ducts, drying kilns, etc. When using a finned bulb, good circulation is required and the bulb is generally installed downstream of the blower or fan.
When heating a liquid in a heat exchanger, a MK80 can be used with the bulb installed in the downstream piping to measure the exiting temperature of the product.
PRINCIPLE OF OPERATION
The actuator is connected to a sensing bulb by a capillary system that is filled with a volatile fluid that, when heated, begins to vaporize creating pressure in the system that works on the diaphragm to either open (reverse acting) or close (direct acting) the valve. Mechanical temperature regulators are the most affordable way to effectively control temperature.