subject: Thermowell Faq: What's A Thermowell? When To Use It? [print this page] Look here for answers to frequently asked questions about your thermowell or thermocouple.
Question: What is a thermowell?
Answer: The definition of a thermowell is a hollow, tube-like receptacle used in conjunction with other industrial temperature measurement devices. A thermowell's purpose is to protect the thermometer device when measuring highly corrosive or high heat materials, such as in chemical processing, food manufacture, the beverage industry, and refining.
To use a thermowell, you insert a temperature-sensing device (usually a thermocouple) inside the thermowell; the temperature-sensing device can then measure the temperature of materials through a tube or pipe, which dips into a vat of materials being processed or refined. The thermowell may be permanently attached to processing equipment, or it may be inserted to the equipment as the need arises. You can measure the temperature of materials
Question: What are the advantages of using a thermowell along with a thermocouple?
Answer: Thermowells protect the industrial temperature measurement device from corrosion, high temperatures, high velocity, and other factors that can damage sensitive equipment and lessen its accuracy (as when a corroded thermocouple gives faulty readings) or ruin it completely. In addition, a thermowell aids in convenience and safety because it and allows you to take the temperature of materials without opening up a sealed container or vat of materials, which may cause explosion or other problems. By using a thermowell, you can also recalibrate the temperature measurement device or use a different thermocouple as your needs change or based on your instruments' performance.
Question: I know that thermowells are made in all sorts of materials-from metals to PVC to bimetals. How do I know which materials will be best for my application?
Answer: You should choose a thermowell based on what you will be using it for. There is a standard guide that if you will be using a thermowell in high velocity or high-pressure environments, you will need a generally more durable thermowell made of more durable materials. There are tables that can tell you what kind of material is best for your needs. For cement manufacturing, you will need ceramic or Chrome Iron. For chemical processing, you will need to allow the corrosiveness of the chemicals being processed to be your guide, but generally stainless steel, or a bi-metal blend of stainless steel and aluminum, nickel, or some other metal is preferred.
For wine and whiskey manufacturing, stainless steel and nickel is generally used. Wrought iron thermowells are used in the food industry, in baking ovens and sugar refining, while stainless steel is used in processing fruits and vegetables. Every type of industry requires a thermowell made of specific materials. If in doubt, consult your thermowell supplier.
