Regular maintenance and overhaul of transformer clamps can timely detect problems and extend their service life. During maintenance, check whether the surface of the clamps is rusted or deformed. If there is rust, it can be cleaned and repainted with anti-corrosion paint. For welded parts, check for cracks, desoldering, and other phenomena, and repair welding in a timely manner if problems are found. During overhaul, focus on the stress situation of the clamps, check whether the tension screws are loose, and whether the iron core and clamps are closely matched. If there is any abnormality, adjust or replace the components in a timely manner to ensure that the clamps are always in good working condition.
Key Points of Customized Design for Transformer Clamps
The customized design of transformer clamps is a systematic project that needs to comprehensively consider various factors, and the design differences in different scenarios are reflected in every detail. For miniature distribution transformers with a capacity below 50kVA, the core of the clamp design is lightweight and compact. Usually, cold-rolled steel plates with a thickness of 2-3mm are used for precision stamping forming. The frame height is only 1/3 of the iron core window height, and the part in contact with the windings adopts an arc transition design, with the fillet radius controlled above 5mm. This can not only reduce wear on the winding insulation, but also save about 15% of the installation space. The diameter of the fixing bolts for such clamps is mostly M8-M10, and a countersunk head design is adopted. The height difference between the bolt head and the clamp surface does not exceed 1mm, avoiding protrusions in narrow spaces.
For large power transformers with a capacity exceeding 10000kVA, the clamps need to have super strong bearing capacity. Their main frame is mostly welded with thick-walled channel steel of model Q355B. The web thickness of the channel steel can reach 12-16mm, and the flange width exceeds 100mm. Welding is performed by carbon dioxide gas shielded welding, the weld leg height is not less than 8mm, and each weld must undergo ultrasonic flaw detection to ensure no pores, slag inclusions and other defects. To adapt to the huge iron core and windings, such clamps will reserve up to 20-30 connection interfaces, including tie rod holes with a diameter of 20-30mm, bolt hole groups with a spacing of 50-80mm, etc. The processing accuracy of all hole positions is controlled within ±0.2mm to ensure precise matching with pull plates, pressure nails and other components.
In the customized design for special environments, for coastal or humid areas with a relative humidity exceeding 90%, the anti-corrosion treatment of the clamp will adopt a three-layer coating system of "phosphating + epoxy primer + polyurethane topcoat", with a total thickness of 80-120μm, among which the primer thickness is not less than 40μm, which can effectively isolate the contact between water vapor and steel. In industrial plants with a vibration frequency of 10-50Hz, a nitrile rubber buffer pad with a thickness of 10-15mm will be installed between the clamp and the foundation. The Shore hardness of the buffer pad is 60±5 degrees, and the compression amount is controlled between 15%-20%, which can reduce the vibration acceleration transmitted to the foundation by more than 40%.
