How to use a dial indicator and feeler gauge to detect the parallelism between the output shaft and the load axis of the NRV040-1:20 reducer

To detect the parallelism between the output shaft and the load axis of the NRV040-1:20 reducer, the core is to measure the radial deviation with a dial indicator and assisted verification with a feeler gauge to ensure that there is no tilt or offset between the two axes. The specific operations are as follows:

1. Clarify testing standards

• Allowable deviation of parallelism: ≤0.1mm/m (radial deviation), angular deviation ≤0.05mm/m.

• Detection core: The two axes must meet the requirements in the 'radial direction' (left and right/up and down offset) and 'angular direction' (tilt) before the parallelism reaches the standard.

2. Tool preparation and preliminary preparation

• Necessary tools: dial indicator with an accuracy of 0.01mm, magnetic meter base, 0.01-1mm feeler gauge, level, and wrench.

• Preliminary cleaning: Wipe the outer circles of the two shafts and the flange end surfaces to remove oil stains and burrs to avoid affecting the detection accuracy.

• Preliminary fixation: Do not tighten the reducer foot bolts temporarily, leaving room for adjustment to ensure that there is no axial movement of the shaft during testing.

3. Dial indicator detects radial parallelism (core step)

• Fixed meter base: Attach the magnetic meter base to the output flange of the reducer, place the dial indicator probe vertically on the outer circle of the load shaft (near the coupling end), pre-pressure 1-2mm and adjust to zero.

• Multi-point detection: Record the dial indicator readings in the four directions of 'up, down, left, and right' of the load axis.

• Calculate the radial deviation: take the difference between the maximum reading and the minimum reading. If the difference is ≤0.1mm, the radial parallelism reaches the standard.

• Repeat verification: Move the dial indicator to the other end of the load shaft (away from the coupling), repeat the above steps, and the deviations at both ends must meet the requirements.

4. Feeler gauge assists in detecting angular parallelism

• Fit the end faces: Butt the coupling flanges of the two shafts (without tightening the bolts) to ensure that there is no obvious gap on the flange surfaces.

• Feeler gauge measurement: Use a feeler gauge to insert the detection gap at the four symmetrical positions of 'upper, lower, left, and right' on the flange end face.

• To determine the angular deviation: the gap difference at the four positions is ≤0.05mm/m (converted according to the flange diameter, for example: the flange diameter is 80mm, the gap difference is ≤0.004mm), which means the angular parallelism reaches the standard.

5. Adjustment and review

• Radial deviation adjustment: Correct the up and down/left and right deviation by increasing or decreasing the steel gaskets on the reducer feet (number of layers ≤ 3 pieces).

• Angular deviation adjustment: fine-tune the position of the load equipment, or correct the tilt through flange adjustment bolts to ensure uniform feeler gauge detection gaps.

• Recheck after tightening: Tighten the anchor bolts and coupling bolts (tighten diagonally in steps), and check again. If there is no rebound in the deviation, it is the final standard.