Ensuring Tightening Quality in the Assembly of the Circulation Pump in New Energy Vehicle Thermal Management Systems

Taking the circulation pump in the thermal management system of new energy vehicles as an example, this component achieves efficient heat dissipation through coolant circulation. It has extremely high requirements for sealing, structural stability, and assembly consistency, which in turn upgrades the requirements for tightening processes.

Common Failure Issues in the Tightening Process of the Circulation Pump

1. Torque Overrun/Decay

• For hard connections such as metal housings, when tightening at high speed to the contact surface, improper control can easily lead to "torque overrun," causing the final torque to exceed the specified limits.

• For soft connections involving plastic components, torque decay is inevitable, leading to insufficient clamping force and tightening failure.

• Floating Screws and Stripped Threads

• Floating screws can occur in two forms: (1) reaching the target torque but the screw not reaching the contact surface; (2) reaching the target torque and the screw reaching the contact surface but without generating effective clamping force.

• Stripped threads refer to thread damage that leads to clamping force failure.

These common tightening abnormalities, if not promptly managed, can result in insufficient final clamping force. During vehicle operation, bolts may loosen under dynamic loads, causing coolant leakage and severely affecting vehicle performance and safety.

Multi-Strategy Control to Ensure Tightening Quality

Danikor's TTC series screwdrivers support flexible configuration of strategies to meet different material and connection structures:

• Hard Connections: Typically use a "high-speed pre-tightening + low-speed final tightening" two-step tightening strategy. First, high-speed pre-tightening to the contact surface, followed by low-speed final tightening to the target torque. This prevents overrun while improving the precision of the final tightening.

• Soft Connections: Can adopt a multi-step tightening strategy, loading torque in stages to effectively reduce torque decay and ensure the final clamping force.

Additionally, the screwdrivers are equipped with pre-configured strategy templates, enabling quick configuration of tightening strategies. Real-time monitoring of the tightening process, recording of tightening data, and optimization of tightening strategies further enhance tightening quality.

Full-Process Intelligent Error-Proofing and Data Traceability

The TTC tool uses both sensor and current forms to determine whether the torque is qualified. By setting parameters such as torque and angle, it can monitor abnormal issues like floating screws and stripped threads in real-time. Additionally, it can easily activate monitoring for high-floating, stripped threads, and repeated tightening abnormalities, lowering the operational threshold.

The entire tightening process records key data such as slope, torque, angle, and steps, uploading this data in real-time to the MES system. It supports viewing and overlaying historical tightening curves, ensuring traceability of tightening results.

Moreover, the communication connection complies with the industry-standard OP protocol, and tool changeover is achieved with "plug and play," facilitating deployment and maintenance.