Bimetal Thermometer
What is Bimetal Thermometer
A thermometer which uses two different metal strips for converting the displacement of temperature into mechanical. The metals used in the thermometer are steel, copper & brass. These strips are connected and they will enlarge at different rates once they heated.
Benefits of Bimetal Thermometer
No power source required
Bimetallic thermometers do not need any electricity or battery to operate, which makes them convenient and economical to use.
Low cost
Bimetallic thermometers are relatively cheap to manufacture and purchase, which makes them affordable for various applications.
Robust construction
Bimetallic thermometers are made of durable and corrosion-resistant metals, which makes them suitable for harsh environments and long-term use.
Easy to use
Bimetallicthermometers are simple and straightforward to use, as they do not require any calibration or adjustment, and they display the temperature directly on a scale or a dial.
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We offer competitive pricing for our services without compromising on quality. Our prices are transparent, and we do not believe in hidden charges or fees.
Best After Service
Provide professional installation and training. Detailed operation manual and video for customer installation. Any problems will be solved within 24 hours. Broken parts will be sent to customer by air during guarantee period.
State-of-the-art Technology
We use the latest technology and tools to deliver high quality services. Our team is well-versed in the and advancements in technology and uses them to provide the best results.
The thermometer is new out of the box. Especially when you do not know the supplier or manufacturer all that well, it would probably be a good idea to at least check whether the thermometer is close to being accurate. If the thermometer is supplied with a valid calibration report, you do not need to test it. This means that either the supplier or the manufacturer of the product has tested it's accuracy and possibly also calibrated the thermometer. A valid calibration report will show when it was done, by whom and also how accurate the thermometer was found to be.
You or someone else dropped the thermometer on the floor. Although this seems insignificant, the fall may have shifted the nut behind the dial a little bit. Because a little bit can already be too much in terms of accuracy loss, you should probably check if the accuracy is still up to par.
You switch the thermometer to a different temperature range. This is especially the case if the thermometer has been used in a certain temperature range for a long time. If the difference between the new and old range is large (let's say twice or half as big) then it is a good idea to check accuracy. Longer exposure to a specific temperature range may make the thermometer less sensitive or even less accurate in other temperature ranges.
The thermometer has been stored for a long time. Similar to the previous reason, but probably more intuitive. The thermometer has spent a lot of time on a shelf, so the thermometer is probably less sensitive to other temperature ranges to which it is going to be exposed.
When you suspect the temperature indicated is not accurate. Quite obvious, but if the thermometer starts to indicate things you are not believing, then it is a good time to check it's accuracy. A common example of this is that your AC in the room is set to 21°C, but the bimetal thermometer indicates something like 24°C. This would be a clear sign that the thermometer needs to be calibrated.
Bimetal thermometers are precision instruments designed for measuring temperature through the expansion and contraction of two different metals bonded together. These devices operate on the principle that the metals have different coefficients of thermal expansion, causing the bimetallic strip to bend with temperature variations.Bimetal thermometers find extensive applications across various industries, including HVAC, automotive, food and beverage, and pharmaceuticals, due to their reliability, durability, and accuracy in temperature measurement. The market for bimetal thermometers is driven by the increasing demand for high-precision temperature monitoring in industrial processes, ensuring optimal performance and compliance with stringent regulatory standards.
Opportunities in the bimetal thermometers market lie in technological advancements, particularly in sensor design and connectivity features. The integration of smart technologies and the Internet of Things (IoT) in bimetal thermometers enable real-time monitoring and data collection, enhancing their usability and efficiency in diverse applications. Additionally, the growing emphasis on energy efficiency and sustainability in industrial processes presents a significant avenue for market expansion, as bimetal thermometers contribute to optimizing energy consumption through accurate temperature control. Segmentation of the market is evident based on end-user industries, with notable sectors including manufacturing, healthcare, and aerospace. Geographically, the market is distributed across regions with a strong industrial presence, emphasizing the importance of bimetal thermometers in maintaining operational stability and quality assurance across diverse applications.
Installation of bimetal thermometer
In order to have sufficient heat exchange between the measuring end of the thermal resistance and the measured medium, the location of the measuring point should be selected reasonably and try to avoid installing thermal resistance near the dead corners of valves, elbows, pipes and equipment.
The thermal resistance with protective sleeve has heat transfer and heat dissipation loss. In order to reduce the measurement error, the thermocouple and thermal resistance should have sufficient insertion depth
For the thermal resistance measuring the temperature of the fluid in the center of the pipeline, the measuring end should generally be inserted into the center of the pipeline (vertical installation or inclined installation). If the pipe diameter of the fluid to be measured is 200 mm, the insertion depth of the thermal resistance should be 100 mm
For temperature measurement of high-temperature, high-pressure and high-speed fluids (such as main steam temperature), in order to reduce the resistance of the protective sleeve to the fluid and prevent the protective sleeve from breaking under the action of the fluid, a shallow insertion method of the protective tube or a hot-jacket thermal resistance can be adopted . Shallow plug-in type thermal resistance protection sleeve, the depth of its insertion into the main steam pipe should not be less than 75mm; the standard insertion depth of thermal sleeve type thermal resistance is 100mm
When the measuring original insertion depth exceeds 1m, it should be installed vertically as much as possible, or a support frame and protective sleeve should be installed
Types of bimetallic thermometer
Helix strip bimetallic thermometer
A helix-shaped bimetallic strip is used to measure the temperature in this type of thermometer. The pointer is connected through the shaft at the free end of the strip. As the temperature increases, the helical strip senses the temperature change. The strip metal with a higher coefficient of thermal expansion expands and winds up along the stem, rotating the shaft. This rotation causes the pointer to move its position in the dial which indicates the media's temperature. As the temperature decreases, the metal with a lower coefficient of thermal expansion shrinks and rotates the shaft. The pointer then reads the lower temperature in the dial.
Spiral strip bimetallic thermometer
A spiral-shaped strip is used to measure the temperature in a bimetallic spiral strip thermometer. As the temperature rises, the two metal strips expand differently. This creates a bending effect and the strip coils in such a way that the metal with a higher thermal coefficient forms the outer side of the arc. As the temperature decreases, the metal with a lower thermal coefficient forms the inner layer of the arc. The pointer and dial attached to the spiral read this deformation which indicates the media's temperature.
Operating Principle of Bimetal Thermometers
Bimetal thermometers work on the principle that solids expand or contracts depending on the temperature.these temperature measurement devices contain two strips of metal, each with a different expansion coefficient. This means that at the same temperature, the two metals will expand or contract at different rates. The materials are usually steel and copper or steel and brass, depending on the measuring range.
The two strips are welded or bonded together, formed into a helical or spiral coil, and placed in the thermometer's stem. The bimetallic coil is affixed at the stem end, while the other end rotates and moves the pointer. As the temperature increases, the strip bends toward the metal with the lower temperature coefficient and creates a rotational movement in one direction. Conversely, as the temperature decreases, the strip bends toward the metal with the higher temperature coefficient and creates a rotational movement in the other direction.
Main technical parameters of Bimetallic Thermometers
Product implementation standard: JB/T8803-1998
Nominal diameter of dial: 60,100,150
Accuracy grade: (1.0), 1.5
Thermal response time: ≤40s
Protection level: IP55
Angle adjustment error
The angle adjustment error should not exceed 1.0% of its range;
Return difference: The return difference of the thermometer should not be greater than the absolute value of the basic error limit;
Repeatability: The repeatability limit range of the thermometer should not be greater than 1/2 of the absolute value of the basic error limit.
Bimetal Thermometer Selection criteria
Stem Size: The stem size determines the insertion depth into the measured medium. Thicker stems provide better thermal conductivity and faster response times. Choose a stem length sufficient to reach the point of interest in the medium while avoiding unnecessary immersion to minimize thermal lag.
Connection Type: The connection type determines how the thermometer mounts or connects to the equipment. There are threaded, fixed flange, union, and ones with compression fittings. Thermowells offer additional protection for the stem in harsh environments.
Temperature Range: Bimetallic thermometers typically cover a wide range, from -70°C to +600°C, depending on the specific model and metal combination. Choose a range covering the expected operating temperatures with some buffer (e.g., 20% above and below). Operating outside the range can damage the bimetallic strip and affect accuracy.
Mounting Type: Under-connection (stems and process connections below the cabinet) is useful in tight spaces with its compact design and protected connection. However, accessing the connection or reading the temperature might be trickier. Rear-connection (stems and process connections located behind the cabinet) provides easy installation and clear readings but exposes the stem and requires more space behind the equipment.
Accuracy Class: The accuracy class is a tolerance level for how much the thermometer's indication can deviate from the actual temperature.
The common accuracy classes are the following:
- Class 1: ±1% of full-scale range (highest accuracy)
- Class 2: ±2% of full-scale range (most common)
- Class 3: ±3% of full-scale range (suitable for less critical applications)
Material compatibility: Ensure the bimetallic strip materials are compatible with the measured medium.
- IP protection: Choosing an IP rating depends on the environment:
- Low dust/moisture: IP54 (dustproof, splashproof).
- Moderate dust/moisture: IP65 (dustproof, water jet protected).
- High dust/moisture: IP67 (dustproof, submersible up to 1m).
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The company is a "New Third Board" listed enterprise, an certified high-tech enterprise, a project undertaking organization of the National Torch Program, a certified enterprise technology center of Chongqing, a 'Specialized, Refined, Differential and Innovative(SRDI)' enterprise, a contract-abiding and trustworthy enterprise, a heat treatment industry technological innovative enterprise, one of the top 10 private scientific and technological innovation enterprises of Beibei District, Class-A tax-paying enterprise, and an Honest Beibei Merchant. Our trademark was assessed as a Famous Trademark of Chongqing.
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FAQ
Q: What is the basic principles of bimetallic thermometer?
Q: When should you use a bimetallic thermometer?
Q: What is the maintenance of bimetal thermometer?
Q: How can I improve my bimetallic thermometer accuracy?
Q: How accurate is a bimetal thermometer?
Q: How often should most thermometers except for bimetallic?
Q: How often should your bimetallic thermometer be calibrated?
Q: When should bimetal thermometers be calibrated?
Q: Can you calibrate a bimetallic thermometer?
Fill the glass with cold water. Insert your thermometer stem into ice water. Let sit until the dial on the indicator head stops moving. Adjust the thermometer, so it reads 32°F (0°C).
Q: What are the advantages of a bimetallic thermometer?
Q: What are the two 2 ways to correctly calibrate a thermometer?
Q: What are the features of bimetallic thermometers?
Q: What metal is used in bimetallic thermometers?
Q: What does bimetal instant read thermometer mean?
Q: Which thermometers Cannot be calibrated?
Q: What is the most common method used to calibrate bimetallic stemmed thermometers?
Q: What is the ideal range on a bimetallic stemmed thermometer?
They have a limited working temperature range though, often between 30 and 300 degrees centigrade (86 to 375 degrees Fahrenheit). They find the most use in the food safety and food preparation industries.
Q: Why is my thermometer not reading correctly?
Q: How accurate is a bimetallic thermometer?
Q: How often should most thermometers except for bimetallic?
As one of the leading bimetal thermometer manufacturers in China, we warmly welcome you to buy bimetal thermometer made in China here from our factory. All customized products are with high quality and competitive price.
Bimetal Thermometer