Project Background
An automation equipment manufacturer used vertical guide posts in an assembly machine for component pressing, positioning, and inspection. After continuous operation, the guide posts gradually developed excessive movement, increased friction noise, and occasional jamming, which affected the stability and repeatability of the assembly process.
The original structure used standard metal bushings. Direct contact between the metal guide posts and metal bushings required frequent lubrication. As the inner surfaces wore over time, the operating clearance increased, causing the guide posts to move sideways during reciprocating motion. Lubricating oil could also contaminate the equipment, workpieces, and surrounding production area.
Original Problems
- The guide posts moved sideways during repeated vertical operation.
- Metal bushings required frequent lubrication and maintenance.
- Excessive clearance reduced positioning accuracy.
- Long-term operation caused abnormal noise, wear, and occasional jamming.
POM Guide Bushing Solution
Based on the guide post diameter, mounting seat dimensions, reciprocating stroke, operating frequency, and installation position, we machined custom POM guide bushings and installed them between the guide posts and mounting seats.
The bushings created an independent sliding and guiding surface. During machining, the inner diameter, outer diameter, concentricity, and installation clearance were carefully controlled. The inner bore needed to allow smooth reciprocating movement while maintaining sufficient guidance to prevent excessive vibration and lateral movement.
Chamfers were added to the bushing openings to simplify installation and allow the guide posts to enter smoothly. This reduced the risk of impact, edge damage, and jamming during operation.
Why POM Was Selected
Polyoxymethylene (POM) offers good mechanical strength, wear resistance, dimensional stability, self-lubricating performance, and a low coefficient of friction. These characteristics make it suitable for guide bushings, bearing sleeves, sliding blocks, positioning components, and other precision engineering plastic parts.
Compared with conventional metal bushings, POM guide bushings reduce direct metal-to-metal contact, operating noise, vibration, and surface wear. They also require less lubrication, helping prevent oil contamination in automated assembly machines, packaging equipment, testing systems, and electronic product production lines.
Project Results
After the POM guide bushings were installed, the guide posts moved more smoothly during vertical reciprocating operation. Sideways movement, friction noise, and occasional jamming were significantly reduced.
The guide posts also entered the working position more consistently, helping improve repeat positioning accuracy and operating stability. When wear eventually occurs, the POM bushings can be removed and replaced separately without replacing the complete guide post or mounting seat.
This solution reduced maintenance costs, lubrication requirements, and equipment downtime while helping extend the service life of the guide post system.
Project Summary
This project used custom POM guide bushings to address unstable guide post movement, metal wear, frequent lubrication, operating noise, and positioning errors in automated assembly equipment.
We can machine POM guide bushings in different sizes and structures according to drawings, samples, installation positions, operating speeds, loads, and actual working conditions. Production schedules are arranged to maintain machining quality while meeting the required delivery date.
