CNC machine tool mechanical parts installation and debugging considerations - Solutions - Huaqiang Electronic Network

The quality of CNC machine tool installation and commissioning directly impacts the average trouble-free working time of these machines. A high-quality installation not only improves performance but also reduces downtime, lowers maintenance costs, and increases overall efficiency during operation.

1. Precautions for Installation and Commissioning of Spindle Bearings

(1) Single Bearing Installation and Adjustment

During assembly, it's crucial to align the eccentricity of the spindle positioning inner hole with that of the spindle shaft as closely as possible. Similarly, the eccentricity of the bearing inner ring and raceway should be matched. This helps minimize the overall eccentricity after assembly, ensuring smooth and accurate operation of the spindle.

(2) Two-Bearing Spindle Installation and Adjustment

When installing two bearings, the front and rear support bearings should have the same eccentricity. The front bearing must be of higher precision than the rear one to reduce the eccentricity at the front end of the spindle component. When disassembling, make sure to mark the circumferential position of the bearing before removing it, so that the original alignment can be restored during reassembly. This helps maintain the integrity of the spindle system and minimizes vibration or misalignment issues.

For bearings with interference fit, use hot or cold mounting methods rather than forceful installation. Avoid using excessive impact, as this can damage the bearing and affect the machine’s performance.

2. Installation and Commissioning of Ball Screw Nut Pair

The ball screw nut pair is designed to handle axial loads only. Any radial forces or bending moments can cause unwanted stress on the ball screw, potentially leading to permanent damage. Therefore, when installing the ball screw nut pair, consider the following:

(1) Movement within Effective Stroke

Ensure the ball nut moves within the effective stroke range. Set limits at both ends to prevent the nut from falling off the screw, which could result in ball loss and system failure.

(2) Non-Self-Locking Nature

Ball screws are highly efficient but not self-locking. If used vertically, ensure that the weight of the component is balanced. Otherwise, gravity may cause reverse motion after power is cut off. To prevent this, use a worm gear drive or an electric brake system.

(3) Alignment of Axis

The screw axis must be parallel to the guide rail axis. The center of the bearing seat at both ends and the nut seat must align at three points to ensure proper function and reduce wear.

(4) Handling During Installation

Do not remove the nut from the screw shaft unless necessary. If removal is required, use an auxiliary sleeve to prevent the balls from falling out during loading or unloading.

(5) Proper Installation of Nut

Avoid impact and eccentricity when installing the nut into the nut seat. This ensures even contact and prevents premature wear.

(6) Protection Against Contamination

To protect the ball screw from chips and dust, install a protective cover such as a wrinkle protection cover or a spiral steel belt. In environments with heavy dust, consider adding sealing devices at both ends of the screw and nut to extend the life of the system.

3. Key Points for Linear Rolling Guide Installation and Commissioning

(1) Gentle Handling

Handle the linear guides carefully during installation to avoid damaging the guide rail due to impact or rough handling.

(2) Proper Slider Management

Never detach the slider from the guide rail or push it beyond its stroke. If installation is difficult, use the guide rail as a reference to remove the slider safely.

(3) Pair Installation Techniques

When installing linear rolling guides in pairs, start by fixing the main rail. Align the reference side of the guide rail with the mounting step and tighten the bolts. Then, use the main rail as a reference to install the auxiliary rail. Ensure parallelism and flatness between the two rails before securing the slider bolts in sequence.