I. Preparation Before Installation: Precise Matching to Avoid Installation Problems
Verify Thread Specifications
Ensure that the thermocouple's thread (such as M6, M10, G1/2, etc.) perfectly matches the pre-drilled hole in the equipment. Pay special attention to imperial (such as 3/4″) and metric (such as M27×2) threads, which may have similar outer diameters but different pitches. Forcing them together may lead to stripped threads or seal failure.
Check the配套 parts
Prepare anti-loosening washers, sealing rings, or high-temperature gaskets to enhance sealing and prevent loosening due to vibration.
Confirm Operating Conditions
Clearly define the temperature, pressure, and corrosiveness of the measured medium, and select the appropriate protective tube material (such as 316 stainless steel for corrosion resistance) and applicable calibration type (such as K-type, suitable for most industrial applications).
II. Installation Process: Standardized Operation to Ensure Reliable Contact
Correct Tightening Torque
After initially screwing it in by hand, use a wrench to tighten it moderately. Do not overtighten to avoid crushing the internal ceramic insulator or causing the protective tube to deform or rupture.
Ensure Sufficient Contact at the Measuring End
When measuring fluid temperature, the thermocouple should be inserted to a sufficient depth, generally 8-10 times the diameter of the protective tube, ideally more than 10 times, to ensure the measuring end is in the area of maximum flow velocity;
When measuring solid surface temperature, the measuring end should be in close contact with the measured surface. If necessary, a spring-loaded structure can be added to maintain contact pressure.
Avoid Interference from Installation Location
Keep away from valves, elbows, pumps, and other areas prone to turbulence or temperature gradient changes. Domain, select representative temperature measurement points to prevent measurement distortion.
III. Wiring and Protection: Details Determine Measurement Accuracy
Correct Use of Compensating Wires
Compensating wires matching the thermocouple type must be selected (e.g., KX type for K type);
The polarity must not be reversed, otherwise, a reverse thermoelectric potential will be generated, leading to severely low or fluctuating temperature readings;
The ambient temperature at the compensating wire connection should be below 100℃ to avoid high temperatures damaging the insulation or affecting the compensation effect.
Moisture-proof and Dust-proof Junction Box
The outlet holes of the junction box should be installed downwards or equipped with waterproof elbows to prevent moisture and dust from entering and causing short circuits; in humid environments, it is recommended to seal the terminal block with wax.
Install Protective Sheath (Optional)
In high-temperature, corrosive, or severely abrasive environments, a protective sheath can be pre-welded, and then the thermocouple can be screwed into it, facilitating later replacement without affecting equipment operation.
IV. Post-Installation Verification: Ensuring Normal System Operation
Conduct Power-on Test
After connecting the display instrument, observe whether the initial reading is reasonable and whether there are jumps, negative values, or over-range phenomena.
Perform Preliminary Calibration
Use a standard temperature source (such as a dry well furnace) to compare the thermocouple on-site and confirm that the error is within the allowable range.
Record Installation Information
