Temperature Measurement


Tech Tip: Insertion and thermowell lengths for electrical thermometers

July 2007 Temperature Measurement

Calculation of insertion lengths of electrical thermometers

Various basic requirements have to be met in order to ensure a precise and quick temperature measurement. One of the most essential requirements is the close interaction between measuring insert and thermowell.

* Measuring inserts of electrical thermometers should butt against the inside of the thermowell bottom.

* Measuring inserts are spring-loaded (see arrow) to balance thermal expansion and possible manufacturing tolerances. The tip travel is approximately 10 mm.

* In order to ensure an optimal thermal connection to the process, the diameter of the measuring insert should match the bore of the thermowell (gap width not more than 0,5 mm). Unfortunately, it is not always possible to meet this in practice. This is why the proper interaction of insertion length and thermowell length are all the more important.

Distinction is made between:

* Thermowells with tip thickness ≤5,5 mm: The insertion length of the thermometer corresponds to the overall length of the thermowell.

* Thermowells with tip thickness >5,5 mm: These are generally solid machined thermowells with screwed connection. In this case, the insertion length of the thermometer corresponds to the overall length of the thermowell less half of the tip thickness. The value resulting from this calculation should be rounded up to a one-digit value next in ascending order of length.

* Thermowells with tip thickness >10 mm: Users are advised to contact the supplier's technical support department for recommendations.

This Tech Tip was provided by Wika.



Credit(s)



Share this article:
Share via emailShare via LinkedInPrint this page

Further reading:

Is the HVAC market in SA missing the big picture?
Iritron Temperature Measurement
The South African HVAC market is currently grappling with a pervasive mindset that prioritises lowest cost over value for money and technical excellence. However, this approach overlooks the significant benefits that come with investing in high-quality HVAC solutions.

Read more...
Temperature monitoring in dairies
ifm - South Africa Temperature Measurement
Milk is a natural product whose processing requires precise temperature settings. The Berchtesgadener Land dairy uses innovative temperature sensors from ifm in key process areas.

Read more...
Measuring temperature, relative humidity and dew point temperature
Senseca Temperature Measurement
Senseca’s range of passive or active transmitters measures temperature, relative humidity, and dew point temperature.

Read more...
High definition thermal imagers on steam crackers
Temperature Measurement
AMETEK Land’s high-definition thermal imaging system, the NIR-B-2K, has been selected by one the world’s largest ethylene producers for installation on multiple liquid-feed cracker furnaces.

Read more...
Magnetic field/temperature sensor with IO-Link
Turck Banner Southern Africa Temperature Measurement
Turck Banner’s CMMT condition monitoring sensor detects magnetic field changes on three axes, and thus opens up new application fields.

Read more...
Three ways to conduct thermal inspections
Comtest Temperature Measurement
There’s no universal solution for all infrared inspections with a Fluke thermal camera, also known as a thermal imager. You need to match your method to the type of equipment you’re inspecting and the level of detail you require.

Read more...
New temperature relative humidity and barometric pressure transmitter
Senseca Temperature Measurement
ENVIROsense, a new environmental temperature, relative humidity, relative humidity and, optionally, barometric pressure transmitter has been launched by Senseca, a leader in the design and manufacture of monitoring and measurement instrumentation.

Read more...
The role of alarm annunciators in temperature monitoring
Omniflex Remote Monitoring Specialists Temperature Measurement
Director at alarm annunciator specialist, Omniflex explores the importance of alarm annunciators in temperature monitoring applications, drawing on examples from different industrial settings.

Read more...
Increased safety and control in steel plants
Temperature Measurement
AMETEK Land has helped a major metals industry plant designer to enhance safety, control, and efficiency in steel plants.

Read more...
Industrial water heating solutions
Temperature Measurement
Electrolux (Kwikot) Industrial’s massive water heating tanks are making a name for themselves beyond local borders.

Read more...