1. Prepare tools
Wrench: Prepare torque wrenches, open-end wrenches, plum wrenches, socket wrenches and other tools of appropriate specifications to meet the tightening and inspection requirements of different bolts.
Auxiliary tools: Prepare slotted and cross screwdrivers, needle-nose pliers, diagonal pliers and other auxiliary tools.
Cleaning tools: Prepare brushes, non-woven fabrics and other cleaning tools for cleaning bolts and connection parts.
2. Safety measures
Power off: Before inspection, be sure to cut off the power supply of the welding workbench to ensure that the equipment is completely powered off.
Personal protection: Operators should wear personal protective equipment such as insulating gloves and insulating shoes.
3. Inspection steps
Appearance inspection:
Check whether there are defects such as rust, deformation, and cracks on the surface of bolts and nuts. Severe rust will affect the strength and performance of the bolts. Deformed or cracked bolts need to be replaced.
Check the matching of bolts and nuts to determine whether there is thread slippage or stripping.
Observe whether there are signs of looseness in the connection parts, such as gaps, relative displacement, etc.
Torque detection:
Use a torque wrench to perform torque detection on the bolts in the specified order.
Record the measured torque value and compare it with the standard. If it is lower than the lower limit, the bolt is loose, and if it is higher than the upper limit, the bolt or the connector may be damaged.
Operation inspection:
When the equipment is running, use a vibration detector to detect the vibration of the bolt connection. Abnormal vibration may be a signal of loose bolts or poor connection.
Use an infrared thermometer to measure the temperature of the bolt connection. If it is significantly higher than the surrounding environment or other normal parts, it may be due to the loose bolts causing increased contact resistance and heat.
4. Treatment method
Minor loosening: For slightly loose bolts, first use a brush to remove dust and debris from the bolts and connection parts, and then tighten them to the specified torque value with a wrench of appropriate specifications.
Severe loosening: If the bolts are seriously loose, loosen the bolts first and check whether there is damage or corrosion at the connection. If there is damage, repair or replace the connector; if there is corrosion, clean the corroded parts and apply rust inhibitor, and then re-tighten.
