What is the reason for the inaccurate torque of the bolt tightening machine in Dalian?

What is the reason for the inaccurate torque of the bolt tightening machine in Dalian?

Torque accuracy is a core indicator of the assembly quality of bolt tightening machines. Excessive torque deviation can directly lead to quality issues such as bolt loosening, workpiece fracturing, thread slipping, and product rework, seriously affecting the yield rate of the production line. In actual production, the torque inaccuracy of the tightening machine is not caused by a single fault, but mainly falls into four categories: equipment calibration, mechanical wear, condition adaptation, and operational debugging. Identifying the cause and making targeted rectifications can effectively restore equipment accuracy and ensure stable assembly processes.

Equipment calibration failure is a common cause of torque deviation. After long-term high-frequency operation of servo and electric tightening machines, the built-in torque sensors may experience slight accuracy drift. If not calibrated for a long time, there may be a discrepancy between the actual torque and the set torque. Additionally, if the equipment is not recalibrated after replacing components such as the spindle, drive shaft, and socket, the parameter data may not match, which can directly cause torque inaccuracy, resulting in batch assembly issues such as under-tightening and over-tightening.

Wear and aging of mechanical components can significantly reduce the stability of tightening. For tightening machines that have been in use for a long time, wear of the socket, loosening of the collet, increased bearing clearance, and wear of the drive shaft can all lead to backlash during the tightening process, consuming effective torque and resulting in displayed values meeting standards but actual locking force being insufficient. In addition, poor fit between the socket and bolt head, as well as slipping of the socket, can cause torque transmission loss, leading to fluctuations in torque data and reduced consistency.

Workpiece conditions and material variations are also significant influencing factors. Deviations in thread roughness, hardness, and lubrication among different batches of bolts, as well as dry threads, impurities, rust, or excessive oiling, can alter the thread friction coefficient, resulting in torque fluctuations under the same parameters. Additionally, uneven workpiece mating surfaces, abnormal assembly clearances, and inconsistent material hardness can lead to unstable tightening resistance, causing torque to fluctuate.

Improper parameter setting, installation, and debugging of the bolt tightening machine in Dalian can also lead to malfunctions. Some production lines fail to adjust the speed and torque segmentation parameters according to bolt specifications, resulting in high-speed finishing and excessive instantaneous impact, which can cause torque overshoot. Additionally, equipment installation offsets, shock absorption failures, and vibration resonance during operation can also interfere with the accuracy of torque collection. Regular calibration of equipment, replacement of worn parts, standardization of material standards, and optimization of tightening parameters are necessary on a daily basis to comprehensively eliminate torque deviation issues and ensure stable assembly accuracy.