The application of platinum rhodium thermocouple

Platinum rhodium thermocouple is also called high temperature thermocouple, precious metals platinum rhodium have single platinum rhodium ( Platinum rhodium - 10 Platinum rhodium) And double platinum rhodium ( Platinum rhodium - 30 Platinum rhodium (6) , them as temperature measurement sensor, usually with temperature transmitter, controller and display instrument, such as process control system, to directly measure or control in the production of a variety of 0 Fluid over a range of 1800 ℃, steam and gas medium and solid surface temperature. Platinum rhodium thermocouple for precious metals thermocouple. Accidentally wire diameter provision of 0. 5 mm, allowable deviation - 0. 015 mm, its chemical composition in the name of the positive electrode of platinum rhodium, contain the rhodium was 30%, including platinum was 70%, the negative is extremely platinum rhodium, rhodium for content 6%, therefore, commonly known as the dual platinum-rhodium thermocouple. The thermocouple * long-term high temperature of 1600 ℃, short-term * high temperature of 1800 ℃. Advantages of platinum-rhodium thermocouple: platinum rhodium thermocouple in the thermocouple series has high accuracy *, * good stability, test your area wide, long service life, high temperature limit, etc. Suitable for oxidation and inert atmosphere, can also be short term used in vacuum, but does not apply to reducing atmosphere or containing metal or nonmetal steam atmosphere. B type thermocouple is an obvious advantage don't need a compensation for the compensation conductor, because in the range of 0 ~ 50 ℃ and internal potential is less than 3 & mu; V。 Disadvantages: platinum rhodium thermocouple deficiency is thermoelectric potential, thermoelectric potential rate is small, low sensitive to read, mechanical strength under high temperature to drop, is sensitive to pollution, expensive, precious metals and one-time investment. The working principle of platinum-rhodium thermocouple is platinum rhodium thermocouple is composed of two different components of two ends synthesis loop conductor, not at the same time, when the two junction temperature will produce thermal current in the circuit. If the work end of the thermocouple with the reference when there is a difference in temperature, display instrument will be installed by the thermocouple thermoelectric potential of the corresponding temperature value. Platinum rhodium thermocouple choice: measuring the temperature of the normal during 1000 ~ 1300 ℃ suggest using single platinum-rhodium thermocouple ( Platinum rhodium - 10 Platinum) , measuring the temperature of the normal during 1200 ~ 1600 ℃ suggest using double platinum rhodium thermocouple ( Platinum rhodium - 30 Platinum rhodium (6) So are using temperature range can ensure the service life of platinum-rhodium thermocouple. Types and specifications: type, degree, temperature measuring range ℃ protection tube materials thermal response time gauge d L x WRP - L 130 WRP2- 130年代0 - 1300 high aluminum & lt; 150S Φ 16 300x150 350x200 400x250 450x300 550x400 650x500 900x750 1150x1000 1650x1500 2150x2000 WRP- 131 WRP2- 131 < 360S Φ 25 WRQ - 130 WRQ2 - 130转0 - 1300 < 150S Φ 16 WRQ - 131 WRQ2 - 131 < 360S Φ WRR - 25到 130 WRR2- 130 B 0 - 1600 alumina tube & lt; 150S Φ WRR - 16到 131 WRR2- 131 < 360S Φ 25 measuring temperature and tolerance: thermocouple type code indexing number * high temperature measuring temperature deviation delta t allowed 30 ℃ platinum rhodium - Platinum rhodium 6 WRR 0 ~ 0-1800 B 1600 ± 1. 5 ℃ or & plusmn; 0. T platinum rhodium 10-25% Platinum WRP S 0-0 ~ 1600 1300 ± 1. 5 ℃ or & plusmn; 0. 25% t