Tu 11-75. The alloy wire of tungsten-rhenium annealed graded for thermoelectrodes thermocouples. Specifications.
1.1. Basic parameters and dimensions
1.1.1. The nominal diameter of the wire and limit deviation shall be as specified in table.1.
|Wire diameter, mm||Tolerances for diameter, %|
1.1.2. The cross section of the wire must be circular. Permissible ovality should not exceed the limit deviation for diameter.
1.2. Material feature
1.2.1. Chemical composition of wire alloy of different grades should conform to table.2.
|rhenium||impurities and additives, not more||tungsten|
1.2.3. The value of TEDS developed in the wire of alloy grades VAR-5 (BP-5) and BP-20 paired among themselves in the temperature of the free ends 0 °C, should correspond to nominal values TEDS indicated in table.3 these specifications and tables GOST 3044−74. The permissible deviation of the readings of the thermocouples in °C (temperature of the free ends 0°C) from the values shown in graduirovannam tables, should not exceed ±5°C (up to 1000°C) and ±0.5% of the tabulated values of temperature in the range of 1000−1800°C.
- By agreement with consumer it is permitted to supply wire alloy grades of VAR-5 (BP-5) and BP-20, developing in tandem TEDS, different from the rules specified in table.3 tables TU and GOST 3044−74.
- The maximum temperature calibration termoelektrodny wire 1800 °C.
- Calibration of thermocouples VAR-5/VR-20 to temperatures exceeding 1800 °C until the maximum temperature of possible applications (3000°C), is performed by customers or institutions of the State standards Committee of the Council of Ministers of the USSR (S. F. Institute Sverdlovsk).
|Temperature, °C||The nominal value of TEDS, mV for calibration|
|1700||25,85||To 26.08||Of 25.63|
1.2.5. Termoelektrodny the wire does not have to break down and delaminate when tested in bending.
1.2.6. Wire diameter of 0.1 mm should not have burrs and strokes. The wire diameter of 0.2 mm and allowed more small burrs and touches, visible to the naked eye.
1.2.7. The wire should be wound on a spool (wrap) evenly across its width without any knots and loops and should be easy to get off of the coil. Free Board height of the coil after winding should be not less than 2 mm.
1.2.8. On the coil (wrap) should be wound single piece of wire of not less than 15 m for diameters of 0.20; 0.35 and 0.50 mm and not less than 30 m for a wire diameter of 0.10 mm. note. By agreement with consumer it is permitted to supply more than a short wire ends.