Bring you a comprehensive understanding of nickel chromium - The performance characteristics of silicon nickel K type thermocouple and working principle

I think everybody for K type thermocouple should be very familiar with, but the thermocouple can be divided into a lot of material, thermocouple products now overwhelmed. Nickel chrome - among them Nickel silicon type K thermocouple this product don't know what you know about it? Here you are welcome to discuss with me about the performance and working principle of the thermocouple.

a, the thermocouple, the positive and negative extremely nickel-chromium alloy (containing 10% chromium PK） , the negative is extremely containing silicon 3% nickel silicon alloy ( KN) 。 The cathode paramagnetic, according to this characteristic, with the magnet can be easily identify thermocouple is negative. Feature is the wide temperature range and high temperature performance is stable, the thermoelectric emfs approximate linear relationship with the temperature, cheap, therefore, consumption is the largest a thermocouple. K type thermocouple for continuous use in oxidizing and inert atmosphere. Short-term use temperature is 1200 ℃, the long-term use of temperature is 1000 ℃.

2, K type thermocouple has the following disadvantages:

1, the high temperature stability of the precious metal thermocouple thermoelectric emfs. Under the high temperature, often due to oxidation damage. In the oxidizing atmosphere, 3 in diameter. 2 mm K type thermocouple, at 1100 ℃, 1200 ℃ under the 650 h, more than 0. The class of 75 permissible error;

2, 250 - 550 ℃ within short term thermal cycling stability is bad, even if, at the same temperature point in the process of rise to cool the thermoelectric emfs value is different also, the difference of 2 - 5℃。

3, K type thermocouple cathode, in 150 - 200 ℃ range to a magnetic shift, left at room temperature to 230 ℃ range, dividing value often deviates from the indexing table, especially when used in the magnetic field, often appear thermoelectric emf interference has nothing to do with the time.

4, chronically high flux neutron irradiation environment, due to the negative of Mn, Co and other element transformation, make its stability is poor, great changes have taken place in thermoelectric emfs.

K type thermocouple for EU - index number before 2, for K now.

k type thermocouple which part is which part is the nickel and silicon, nickel chromium alloy is the whole or half is half nickel chrome nickel silicon?

thermocouple: when there are two different conductors or semiconductor A and B to form A loop, its both ends are connected, as long as the temperature of the two nodes is different, one end of the temperature T, called end or hot end work, on the other side temperature T0, known as the free end, Also known as the reference side) Or the cold end, the circuit will generate an electromotive force, the direction and size of the electromotive force is related to the conductor material and the temperature of the two contact. This phenomenon is called & other; Thermoelectric effect & throughout; , two conductors circuit called & other; Thermocouple & throughout; 。

k type thermocouple used in the two different conductor ( Two wires) , is a nickel chrome, another is nickel and silicon.

nickel chromium silicon - Nickel silicon thermocouple ( K type thermocouple) For inexpensive metal thermocouple, it is a kind of new international standard thermocouple, is successfully developed by the Australian defence laboratory, in the early 70 s it overcome the K type thermocouple two important faults: K type thermocouple between 300 ~ 500 ℃ due to the lattice short-range order of nickel-chromium alloy thermoelectric emfs caused by unstable; At about 800 ℃ caused by nickel chrome preferential oxidation thermoelectric emfs instability. The anode ( NP) Chemical composition as follows: in the name of the Ni, Cr, Si = 84. 4:14. 2-1. 4, the cathode ( NN) In the name of the chemical composition is: Ni: Si, Mg = 95. Five. 4-0. For - 1, its working temperature 200~1300℃。

K type thermocouple has advantages of good linearity, thermoelectric emfs is larger, higher sensitivity, stability and good uniformity, oxidation resistance is strong, cheap, is not affected by short-range ordering etc, and its comprehensive performance is better than that of K type thermocouple, thermocouple is a kind of very promising.

K type thermocouple cannot directly at high temperature for sulfur, reducing or reduction, oxidation atmosphere and vacuum alternately, is not recommended for people with weak oxidizing atmosphere.

nickel chromium silicon & ndash; Nickel silicon thermocouple for K type thermocouple, the following introduce K type:

temperature measuring range: - 200 ~ 1200 degrees, the error is divided into class I or class II and class I in accuracy for & plusmn; 1. 5 ℃ or & plusmn; 0. 4% t, grade I precision error is & plusmn; 2. 5 ℃ or & plusmn; 0. 75% t

there are many types of installation structure, a thread installation, flange installation, etc.

as for the thermocouple temperature measurement principle, the basic law, the selection of materials, indexing table, etc. , welcome to reference!

K type thermocouple for above is introduced here, believe everybody to nickel chromium - Nickel silicon thermocouple also have roughly understanding, if there is demand, welcome to contact us at any time three chang instrument, we would be happy to help you ~