The Differences Between Bimetal Thermometers and Gas Expansion Thermometers
There are many types of industrial thermometers. Among them, the common types are bimetallic and gas expansion thermometers. However, some people are often confused about the advantages and disadvantages between these thermometers. So let's look at the differences between these thermometers.
Bimetal thermometers are made of two different kinds of metal bonded together. Each metal expands at different rates when heated, and by measuring this difference, we can measure temperature. Generally, the metal sheets are made into a coil, with the "free end" connected to the pointer shaft and the "fixed end" where the thermometer will be attached. When the temperature rises, the metal at the free end will rotate in one direction, and when the temperature drops, it rotates to the other direction. When the coil bends, the free end will control the pointer.
Gas expansion thermometers, also known as gas-actuated thermometers, use the principle of gas expansion to measure temperature. Helium (He) is generally recommended. When the temperature rises, the gas in the thermometer will expand, changing the pressure in the tube. This pressure drives the pointer.
|
Bimetal Thermometer |
Gas Expansion Thermometer (Gas-actuated Thermometer) |
Temperature Range Limit
|
-70°C ~ 600°C |
-200°C ~ 700°C |
Ambient Temperature
|
No Effect | Affected |
Response Time
|
Slow | Fast |
Measurement Distance
|
Measurement can only be made at measurement point |
Enables long-distance temperature measurement (via capillary) |
Price
|
Cheaper | Higher |
Source: https://www.wika.com/en-en/startpage.WIKA
Each type of thermometer has its own specialization — each with advantages and disadvantages. We help our clients answer the important question: Which one is more suitable to your needs? If you are interested in temperature- or thermometer-related topics, click on Read More.
Be the first to know about SJ Gauge's latest news and updates!
►Related Products:
|
|