I. Mastering the Ideal Tension Standard
1. Press the middle of the conveyor belt with your finger; the sag should be 2%–3% of the belt width. For example, a 1-meter wide belt should sag 2–3 centimeters after pressing.
2. Excessive tension will increase the motor load, accelerate bearing wear, and even cause the belt edges to crack.
3. Excessive looseness can easily cause skipped teeth during startup, inaccurate positioning, or the belt to strike the protective cover during operation.
II. Common Adjustment Methods
1. Mechanical Adjustment Method: Locate the tension screw of the conveyor belt (usually located on the driven pulley or tension pulley bracket). Loosen the fixing bolts and rotate the adjusting screw: clockwise rotation increases tension, counterclockwise rotation decreases tension. After adjustment, test run the belt and observe for any deviation or abnormal noise. Gradually fine-tune until a stable state is achieved.
2. Frequency Method (Recommended): Use a belt tension meter (such as a Gates ultrasonic tension meter) to measure the belt vibration frequency. Refer to a table based on the belt width, span, and material to obtain the target frequency value, and adjust it to the standard range. This method is highly accurate and suitable for high-precision automated equipment.
3. Indentation Method (Empirical Judgment): Apply a vertical force of 1–2 kg at the midpoint of the belt span and measure the sag. Control the sag to 1%–2% of the span (usually 10–15 mm). Excessive sag indicates insufficient tension, while insufficient sag indicates excessive tightness.
III. Key Precautions After Adjustment
1. Secondary Tightening During the Running-in Period: PU conveyor belts will experience slight elongation (stress release) after the initial 24 hours of operation. The tension must be rechecked and fine-tuned; otherwise, it may lead to subsequent slippage or tooth skipping.
2. Regular Inspection: It is recommended to check the tension monthly, which can effectively extend the service life by more than 30%.
3. Forceful Operation Prohibited: Never use a screwdriver to forcibly pry or adjust the installation, as this may cut the internal fiberglass or steel wire core, causing hidden damage and potentially leading to sudden breakage during operation.
IV. Common Abnormalities and Solutions
If skipping teeth occurs during startup, first check if the tension is insufficient and clean any oil stains from the drive roller surface. If the motor overheats severely, it may be due to excessive tension or bearing jamming; loosen the tension appropriately and check for mechanical resistance. Belt slapping protection is often caused by insufficient tension or misalignment; adjust both tension and roller parallelism together.
