NSRH Roots Blower Operation and Maintenance

The NSRH Roots blower is a positive-displacement blower mainly used to convey air and other non-corrosive gases. It is commonly applied in wastewater treatment, pneumatic conveying, aquaculture, chemical processing, and environmental protection. Unlike high-speed centrifugal equipment, it does not compress gas through a high-speed impeller. Instead, the blower changes the working chamber volume through rotor rotation to complete gas intake, compression, and discharge. Its structure is relatively simple and its airflow is stable, but proper installation, lubrication, and temperature control remain important.

1. Working Principle of the NSRH Roots Blower

1.1 Synchronized Rotation of Dual Rotors

The NSRH Roots blower generally contains a pair of parallel lobed rotors. The two rotors rotate in opposite directions at the same speed through synchronized gears. There is a specified clearance between the rotors and between the rotors and the housing, preventing direct contact during normal operation.

As the rotors turn, gas enters the working chambers formed between the rotors and the housing from the inlet side. The trapped gas is then carried toward the discharge side as the rotors continue to rotate.

1.2 Continuous Gas Conveying

When a rotor moves into the discharge area, the working chamber communicates with the outlet and the gas is discharged under the pressure difference. The continuous rotation of the two rotors creates a steady intake and discharge process.

A Roots blower is essentially a forced-displacement conveying device. The actual discharge pressure is largely determined by system resistance. Therefore, the outlet valve should not simply be closed to regulate pressure during operation, as this may cause motor overload and excessive temperature rise.

2. NSRH Roots Blower Operating Guide

2.1 Checks Before Startup

Before startup, check whether the base, coupling, and piping connections are secure. Confirm that the inlet filter is clean and that the lubricating oil level is within the normal range. The condition of the belt or coupling should also be checked, along with safety valves, pressure gauges, and other accessories.

If the blower has been stored for a long period, manually turn the shaft before startup to ensure that the rotors move freely without obvious blockage or abnormal friction.

2.2 Startup and Operation

Before starting, confirm the valve positions according to the equipment manual and check that the motor rotates in the correct direction. After startup, avoid keeping the blower under a heavy load immediately. Gradually observe pressure, current, temperature, and operating noise.

During normal operation, the inlet passage must remain unobstructed. If the pressure suddenly rises, the current increases significantly, or the housing temperature rises rapidly, reduce the load and investigate the cause.

2.3 Shutdown Precautions

For normal shutdown, gradually reduce the load according to process requirements before stopping the blower. After shutdown, check for oil leakage, gas leakage, and abnormal vibration. If the equipment will remain idle for an extended period, protect it against dust, moisture, and corrosion.

3. Routine Maintenance

3.1 Lubrication System Inspection

Lubricating oil is essential for reliable blower operation. During routine inspections, check the oil level, oil condition, and possible leakage. If the oil is visibly deteriorated or contaminated, it should be replaced promptly.

Lubrication methods, oil specifications, and oil-change intervals may differ between NSRH blower models. Actual maintenance should therefore follow the manufacturer's technical documentation.

3.2 Regular Filter Cleaning

Dust accumulation in the inlet filter increases suction resistance and can affect blower operation. The filter element should be cleaned or replaced periodically according to the dust conditions at the installation site.

A severely clogged filter may cause insufficient airflow and excessive temperature rise even when the main blower and motor are operating normally.

3.3 Check Vibration and Temperature

During operation, monitor bearing temperature, oil temperature, vibration, and noise. A normally operating blower should produce relatively steady sound. If periodic knocking, friction noise, or significant vibration suddenly occurs, stop the machine and inspect it.

4. Common Faults and Troubleshooting

4.1 Reduced Airflow

When airflow decreases, first check whether the inlet filter is clogged. Then inspect the piping, valves, and system for leakage. If these components are normal, further inspection of rotor clearance and equipment wear may be necessary.

4.2 Excessive Pressure

Abnormally high pressure is often related to increased system resistance. Check whether the discharge pipeline is blocked and whether the valves are in the correct positions. The safety valve should also be checked to ensure proper operation. Do not maintain high-pressure operation by forcibly closing the discharge-side valve.

4.3 Excessive Temperature or Abnormal Noise

High temperature may be caused by excessive pressure, poor lubrication, a clogged filter, or inadequate heat dissipation. If abnormal noise occurs together with vibration, the bearings, gears, and rotor operating condition should also be inspected.

Overall, the key to using an NSRH Roots blower is proper operation combined with regular inspection. Careful startup checks, lubrication management, filter maintenance, and operating-parameter records can help identify problems at an early stage. When a fault occurs, first determine whether the cause is related to the process system or the blower itself, and then take targeted corrective action. This approach can reduce downtime and extend equipment service life

roots blower product information

Web: http://www.greentechblower.com  (Group Web)  ‖  http://www.zqblower.cn  (Chinese)  ‖ http://www.ringblower.cn/ (Ring blower)  ‖  http://www.china-blower.com  (Roots Blower)