Bolt Heating Rod
Darui Electric recommends
The power distribution cabinet is a dedicated device for bolt heating rods, available in both AC and DC types. The DC cabinet uses a thyristor three-phase full-wave circuit, providing smooth DC output waveform. The thyristor trigger part is made using advanced integrated circuit trigger principles, allowing selection of different heating voltages according to different situations, facilitating the disassembly and assembly of cylinder bolts.
Technical Specifications:
Input Power: AC 50Hz, three-phase four-wire 380V
Output Current: DC ripple frequency 6fo-180V stepless adjustment
Output DC: 12 branches, each independently controlled by a single switch, maximum power per branch 15KW.
(I) Should meet the following requirements:
1. The raw materials used for the electric heater should meet the following requirements:
① The composition of the insulating material magnesium oxide should comply with HG3-1294-80 "Magnesium Oxide";
② Magnesium oxide must be dried before use;
③ The heating material used in the electric heater is 0Cr27A17Mo2 high-resistance electric heating alloy wire, with an operating temperature of 400°C, technical requirements according to GB1234 "High-Resistance Electric Heating Alloy";
④ The protective tube material of the electric heater is 1Cr18Ni9Ti heat-resistant stainless steel tube, technical requirements according to YB804 "Stainless and Acid-Resistant Seamless Steel Tubes". Use of other materials shall be agreed upon by the manufacturer and the user;
⑤ The protective tube used for the electric heater should be deburred internally, then cleaned with gasoline or kerosene, and dried before use.
2. The finished electric heater should meet the following requirements:
① The rated working voltage of the electric heater is 220±20V, DC 100V, low voltage 50V;
② For insertion length within 1m, the straightness of the centerline should not exceed ?0.3mm; for insertion length between 1-2m, the straightness of the centerline should not exceed ?0.4mm;
③ The diameter deviation of the insertion part is -0.20mm/-0.50mm;
④ The length deviation of the insertion part is ±5mm, the heating length deviation is ±5mm, and the cold end length at the bottom is 25-30mm;
⑤ The electric heater should heat evenly during use, without local overheating.
(II) During the life test of the electric heater, each heating time is 10-20min. Under intermittent heating conditions, with the total gap between the bolt center hole and the outer diameter of the electric heater between 0.8-1.3mm, the cumulative life should not be less than 50h.
(III) The connection between the alloy resistance wire and the lead wire should be firm and reliable, without looseness. The shell must be well grounded.
(IV) After cold drawing of the steel tube of the electric heater, the surface should be inspected by dye penetrant testing or with a magnifying glass of 5x or more, and there should be no cracks or other defects. The tube should be formed in one direction during drawing.
(V) The sealing at the cold end of the electric heater should be tight to prevent moisture from entering and damaging the insulation.
(VI) After the electric heater is manufactured, after one and a half months, at room temperature, use a 500V megohmmeter to measure its insulation resistance (can be performed at the manufacturer or user site) should not be less than 50MΩ.
Note: The above information and technical parameters are compiled and released by Yangzhou Darui Electric Co., Ltd.
