Thermocouple production standards

Thermocouple is an industrial, civil, test, scientific research on *, one of the commonly used temperature detection sensor measurement accuracy is high. Thermocouple direct contact with the measured medium, not affected by the intermediate links, using infrared thermometer can't replace. Thermocouple from - 80 ~ + 2300 ℃ can be continuous measurement, some special thermocouple might be more wide range, but not recommended to use temperature is too high.

how it works:

basic principle of thermocouple temperature measurement is conductors of two different material welding, form a closed loop. Two different metal produce thermoelectric potential under the action of temperature, usually enlarge the thermoelectric potential, through intelligent instrument or numerical software or other way, as for how to display the principle of value should not be tired.

conditions:

1. Thermocouple standard content: provides the thermocouple voltage conversion into their corresponding measured temperature and measured temperature is converted into the corresponding thermocouple potential indexing table.

2. Thermocouple standard code: GB/T16839. 2 - 1997

standard content: provides a standard thermocouple electromotive force Made of precious metals and metal thermocouple temperature relationship manufacturing tolerance. Tolerance values apply to delivery to users usually use diameter 0. 25mm- 3 mm wire made of a thermocouple.

3. Industrial thermocouple technology condition

standard code: JB/T9238 - 1999

standard content: rules for industrial thermocouple technical requirements, test methods, inspection rule, packing and marking. Suitable for indexing table and tolerance in accordance with GB/T16839. 1 ~ 2 removable industrial thermocouple.

production standards:

1, the first production will be positive and negative thermocouple diode pair wire for welding, there are three kinds of welding, welding, oxygen welding, argon arc welding, often use argon arc welding, the welding process can be used in the argon gas protection. Welding wire head occasionally garden smooth, no pores. Welding is firm, use for a long time.

2, thermocouple protection tube production: usually the thermocouple protection tube material for: 1 cr18ni9ti, depends on the temperature range. Above materials have different requirements. Thermocouple protection tube in the production process has some strict requirements: first the head, head has two kinds: one kind is to use a lathe from sealing method, under the high speed advantage is thermocouple protection pipe of equivalent material, the heat resistance and can proper use, the disadvantage is that some bad there will be a hole sealing leakage or leakage, if in the harmful gas or liquid using the consequence is unimaginable. * * is with plug seal, which is a plug stuck at the end of the thermocouple protection tube, reoccupy argon arc welded, benefit is under pressure to a few bigger, head thickness uniformity of appearance also is very beautiful; Defect is material does not necessarily equal, if the temperature is high may not satisfied life. Whether it is made of how should conduct stress tests, in case of one thousand has a hole. 3, the thickness of the thermocouple protection tube: want to see the scene of the temperature requirements, thickness not less than 2 mm less *

4, the appearance of the thermocouple protection tube processing, in the past few manufacturer in particular, some old instrument and meter plant, is not let polishing, polishing is just the external surface behind a layer of protection tube, bright beautiful, but not practical. Now because of the increase in technology of stainless steel tube in the process of production can do finish processing, the production need to do some special treatment on the surface. When a layer of inferior smooth appearance looks very dignified, quality also is not lost.

5, thermocouple thread welding requirements: some thermocouple with threads, thread material usually choose 1 cr18ni9ti or 304, or with the same thread material protection tube material, now we use high chromium in some small workshops, some manufacturer is thread by way of casting production, and more formal approach is to use equivalent material materials. Thread of the two must have soldering station, convenient to use argon arc welding. Thread head required to welding.

6, thermocouple protection control process should pay attention to not thrown into the ground, many manufacturers in the wire or polishing process is often with a thrown into the ground, do * * damage protection tube appearance, easy to cause surface scratches,

7, the interior of the thermocouple protection tube cleaning, there are quite a few of the interior of the protecting tube with dirt, be sure to clean up.

8, thermocouple assembly must be tested after the completion.