In the operation of belt conveyors, rollers serve as the core component, bearing more than 70% of the transportation resistance. Due to their high usage frequency and short replacement cycles, special attention must be paid to selecting, using, and maintaining rollers effectively in order to enhance their performance. This article will delve into three key factors—analyzed from a professional perspective—that significantly influence the operational performance of conveyor rollers.

1. Poor Sealing Performance: A Dual Challenge of Dustproofing and Waterproofing

Roller bearings typically feature an axial, non-contact labyrinth seal design, which prevents dust by creating a tortuous gap. However, this sealing method has a significant drawback when it comes to waterproofing. The working environment of underground conveyor systems is particularly challenging—characterized by high dust levels and frequent use of water for dust removal—placing even greater demands on the sealing performance of roller bearings.

If the sealing performance is inadequate, moisture and dust can easily penetrate into the roller bearings. Moisture will corrode the bearings, while dust accelerates bearing wear, ultimately leading to a significant reduction in the roller's lifespan. Therefore, selecting sealing materials with outstanding dustproof and waterproof properties is crucial for ensuring the long-term, stable operation of the rollers.

2. Poor Alignment of Roller Shafts: The Silent Killer of Rotational Resistance

Roller shafts commonly use the cold-drawn polished shaft process, and their surface roughness and dimensional accuracy usually meet specifications without the need for additional machining. However, the production process of cold-drawn polished shafts is susceptible to factors such as die wear, which can lead to unstable dimensional accuracy. Moreover, improper handling during transportation may also cause the shaft to bend, further compromising its coaxiality.

A roller shaft with poor coaxiality cannot ensure uniform clearance at both ends when bearings are installed, thereby increasing rotational resistance. This not only compromises the flexibility of the roller's rotation but may also lead to premature bearing failure, ultimately shortening its overall service life. Therefore, strictly controlling the shaft's coaxiality during both production and transportation is a crucial measure for enhancing the performance of rollers.

3. Poor Coaxiality of Bearing Housing: A Precise Test for Welding Techniques

Roller bearing housings are typically made as stamped components, and the mating areas with the cylinder shell are usually welded directly without further machining. However, if issues such as out-of-roundness or uneven end faces occur during the stamping process, welding may easily result in misalignment between the two bearing housings at their ends. This coaxial deviation can reduce the bearing clearance, significantly increasing rotational resistance—and in severe cases, even causing the bearings to seize up completely.

To ensure the coaxiality of the bearing housing, it is necessary to address this issue from both the stamping process and the welding procedure. Optimizing the stamping die design will enhance machining accuracy, while adopting advanced welding technologies—such as laser-assisted spot welding—can effectively minimize coaxiality errors, thereby guaranteeing smooth operation of the roller assembly.