CM-200→Compressor Connecting Rod Nut Tightening Application
model:CM-200 Application: Automatic Nut Tightening Machine for Connecting Rods
《Case Description》
In the past, the nut-tightening process for compressor connecting rods was mostly performed manually, requiring operators to apply balanced torque on both sides simultaneously. Since the nuts are fixed on the workpiece, completing the tightening in one smooth action is difficult. Long periods of manual operation increase operator fatigue, and the tightening force varies from person to person, often resulting in inconsistent torque, uneven tightening depth, and unstable cycle times. To address these issues, we designed a dedicated automated tightening machine to ensure both nuts on the connecting rod can be tightened synchronously under identical conditions.
The CM-200 adopts a dual-spindle synchronous tightening design. Once the workpiece is placed on the fixture, the left and right clamp arms secure it in position. After pressing the dual-start buttons, both nuts are tightened simultaneously, ensuring consistent torque and improved assembly quality. The machine features a stable clamping mechanism and controlled stroke, effectively reducing errors caused by manual operation. For rework or correction, the reverse-tightening function can be activated to quickly loosen the nuts. The streamlined process shortens the fastening cycle and significantly improves quality stability, making the CM-200 an ideal solution for connecting-rod assembly lines.
This system has already been successfully implemented in multiple compressor-related manufacturing facilities, helping customers reduce manual workload, increase production efficiency, and enhance fastening consistency. Actual production feedback further confirms its stability and excellent performance as a replacement for manual operations.
- Loading
The operator places the compressor connecting rod onto the fixture, aligning the big end with the locating surface so that both nuts match the centers of the nut sockets above. Once the rod is properly seated, the system enters the standby state for the clamping process. - Clamping
After activation, the left and right clamp arms swing inward to secure the big end of the connecting rod. This prevents movement or vibration during fastening, ensuring the nuts remain correctly positioned and torque is applied in the proper direction. - Nut Fastening
Once the rod is clamped, the dual spindles descend simultaneously, with both nut sockets engaging and tightening the nuts at the same time. The system can be set with specific torque and angle requirements, stopping automatically once the target values are reached. This allows both nuts to be tightened in a single cycle with consistent torque and stable takt time. - Complete
After fastening is complete, the spindles return to the home position and the clamp arms open to release the part. The operator then removes the fully tightened connecting rod. This creates a stable, repeatable automatic tightening cycle that improves production efficiency and ensures consistent fastening quality.
Seals Core Technologies & Practical Value
- Dual-spindle synchronous tightening:Tightens both nuts simultaneously, ensuring consistent torque and preventing deviation.
- Automatic fixture positioning:The connecting rod is automatically aligned upon placement, improving loading speed and accuracy.
- Left–right clamp arms:Secure the workpiece before fastening, preventing vibration or displacement.
- Torque/angle control:Tightening conditions can be preset; the system stops automatically once the target is reached for stable quality.
- Tightening and loosening capability:The drivers support reverse rotation, making inspection, rework, and maintenance more convenient.
- Single-operator workflow:Automated processes reduce reliance on operator skill.
- Stable cycle time for high-efficiency production:Consistent operation makes it ideal for mass-production lines.
- Reduced defect rate:Prevents common manual issues such as over-tightening, insufficient torque, or torque variation.
- High-rigidity structure:Suitable for high-torque nut tightening, providing stable and reliable operation.
- Customizable fixtures:Fixtures and clamp designs can be tailored for different connecting-rod sizes and nut specifications.
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