Description
Product introduction:
Temperature Thermocouple sensor WRN-130 WRN-330 WRN-430 WRR-130 WRP-130 is a commonly used temperature measuring component in a temperature measuring instrument. It directly measures the temperature and converts the temperature signal into a thermoelectromotive force signal, which is converted into the temperature of the measured medium by an electric meter (secondary meter). The shape of various thermocouples is often very different due to the needs, but their basic structure is almost the same, usually composed of hot electrode, insulating sleeve protection tube and junction box, etc., usually with display instrument, recording instrument and electronic adjustment Used in conjunction with the device.
In industrial production, temperature is one of the important parameters that need to be measured and controlled. In the temperature measurement, the thermocouple is widely used, and it has many advantages such as simple structure, convenient manufacture, wide measuring range, high precision, small inertia and easy transmission of output signals. In addition, since the thermocouple is a passive sensor, it does not need an external power supply for measurement. It is very convenient to use, so it is often used to measure the temperature of the gas or liquid in the furnace, the pipe, and the surface temperature of the solid.
Thermocouple indexing number |
Thermal electrode material |
|
|
positive electrode |
negative electrode |
S |
Platinum Rhodium 10 |
Pure platinum |
R |
Platinum Rhodium 13 |
Pure platinum |
B |
Platinum Rhodium 30 |
Platinum Rhodium 6 |
K |
Nichrome |
Nickel silicon |
T |
Pure copper |
Copper-nickel |
J |
iron |
Copper-nickel |
N |
NiCrSi |
Nickel silicon |
E |
Nichrome |
Copper-nickel |
Main feature:
1. Simple assembly and convenient replacement;
2, pressure spring type temperature sensing element, good seismic performance;
3. High measurement accuracy;
4, the measurement range is large (-200 ° C ~ 1300 ° C, in special cases -270 ° C ~ 2800 ° C);
5, the thermal response time is fast;
6. High mechanical strength and good pressure resistance;
7, high temperature resistance up to 2800 degrees;
8, long service life.
Installation requirements:
For the installation of thermocouples and RTDs, attention should be paid to the accuracy of temperature measurement.
It is safe, reliable and easy to maintain, and does not affect the operation and production operation of the equipment. To meet the above requirements, pay attention to the following points when selecting the installation location and insertion depth of the thermocouple and the thermal resistance:
1. In order to ensure sufficient heat exchange between the measuring end of the thermocouple and the thermal resistance and the measured medium, the position of the measuring point should be reasonably selected to avoid installing thermocouples near the dead angle of valves, elbows and pipes and equipment. Thermal resistance.
2. Thermocouples and thermal resistors with protective sleeves have heat transfer and heat loss. To reduce measurement errors, thermocouples and RTDs should have sufficient insertion depth:
(1) For thermocouples that measure the temperature of the fluid at the center of the pipe,
Generally, the measuring end should be inserted into the center of the pipe (vertical or inclined installation). If the pipe diameter of the fluid to be tested is 200 mm, the insertion depth of the thermocouple or thermistor should be 100 mm;
(2) For the temperature measurement of high temperature and high pressure and high speed fluid (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, the protective tube may be inserted in a shallow insertion manner or a hot sleeve. Thermocouple, shallow-plug thermocouple protection sleeve, the depth of insertion into the main steam pipe should not be less than 75mm; the standard insertion depth of the thermo-sleeve thermocouple is 100mm;
(3) If it is necessary to measure the temperature of the flue gas in the flue, although the diameter of the flue is 4 m, the insertion depth of the thermocouple or thermistor can be 1 m;
(4) When the insertion depth of the measuring element exceeds 1 m, it should be installed as perpendicular as possible, or the support frame and the protective sleeve should be added.