**Method for gear alignment of two blade Roots fan (detailed explanation with graphics and text)**
The gear alignment of Roots blower is a key step to ensure synchronous operation of the rotor and avoid impeller collision. If the gear alignment is not accurate, it can lead to increased rotor friction, abnormal noise, vibration, and even damage to the equipment. The following are detailed steps and precautions for gear alignment.
---
**1、 Preparation work before gear alignment**
**1. Tool preparation**
|Tool Name | Usage Description|
|----------------|----------------------------|
|* * dial gauge * * | Measure gear mesh clearance and axial deviation|
|* * feeler gauge * * | Check the gear backlash (0.10~0.15mm)|
|* * Copper rod/rubber hammer * * | Lightly tap the gear to adjust the position|
|* * Marking pen * * | Mark the initial position of the gear|
|* * Torque wrench * * | Ensure even tightening of bolts|
**2. Inspection items**
-Gear wear: Check for pitting, cracks, or wear on the tooth surface (severe wear requires replacement).
-Bearing clearance: Check if the bearing is loose (radial clearance ≤ 0.1mm).
-* * Rotor position * *: Manually turn the rotor to confirm that it can rotate freely without any jamming.
---
**2、 Gear alignment steps**
**1. Position the initial meshing mark**
-The gears of Roots blowers usually have * * meshing marks (such as "0" or "△") * * when they leave the factory, and these marks need to be aligned before centering.
-If the marking is blurry, you can manually rotate the gear and find the non-contact position of the rotor as the reference.
**2. Adjust gear phase**
1. * * Loosen the gear fixing bolts * * (usually 4-6), but do not remove them.
2. Use a copper rod to lightly tap the gear and adjust its angle to ensure even clearance between the impellers of the two rotors (standard: 0.10~0.20mm).
3. Use a feeler gauge to check the gear backlash (normal range: 0.10~0.15mm).
**3. Tighten the gear bolt**
-* * Tighten the bolts gradually in diagonal order * * (to avoid gear misalignment).
-Use a torque wrench to tighten according to the manufacturer's required torque value (usually 30-50N · m).
**4. Verify the alignment effect**
1. * * Manual turning * *, rotate several times, confirm that there is no abnormal friction or jamming.
2. Use a dial gauge to check the axial runout (should be ≤ 0.05mm).
3. * * Trial operation * *: Start by tapping and observe whether the current and vibration are normal.
---
**3、 Common problems and solutions**
|* * Problem * * | * * Possible Cause * * | * * Solution * *|
|---------------------|---------------------|--------------------------------|
|* * Gear abnormal noise * * | Poor meshing or wear | Re align or replace the gear|
|* * Rotor Friction * * | Gear Phase Error | Adjust the gear angle to ensure even clearance|
|Excessive vibration | Unbalanced gears or damaged bearings | Check dynamic balance or replace bearings|
|* * Loose bolt * * | Not tightened to standard torque | Use torque wrench to tighten again|
---
**4、 Precautions**
1. * * The machine must be shut down for operation * *, and it is forbidden to adjust the gear during operation!
2. * * After the gear is aligned, the impeller clearance * * needs to be retested (standard 0.10~0.20mm).
3. * * Regularly check the gear oil * * (replace it every 3-6 months).
4. If the gears are severely worn, they must be replaced in pairs to avoid a mismatch between the old and new gears.
---
**5、 Summary**
-* * Key points * *: Align meshing marks → Adjust gear phase → Uniformly tighten bolts → Verify operating status.
-* * Suggestion * *: When centering or replacing gears for the first time, it is recommended to have a professional perform it to avoid equipment damage caused by operational errors.
By following the above steps, it can be ensured that the gears of the two blade Roots blower are correctly aligned, which extends the service life of the equipment!
