Process and steps for commissioning and test run of Roots blower for sewage treatment:

Installation acceptance of Roots blower → check the wiring of Roots blower starting cabinet and switch the change-over switch to manual position → open the air outlet pipe valve of Roots blower → jog Roots blower to check the fan rotation → start Roots blower → check the fan operation → check the air outlet of air duct (observe the backwashing air outlet) → Check the pressure change of air outlet pressure transmitter and mechanical pressure gauge → Shut down → Switch the change-over switch of fan starting cabinet to automatic → Start/stop Roots blower at PLC panel or central control room operation station → Switch the change-over switch of field control cabinet to the stop position → Start/stop of fan shall be invalid

(1) The fan shall meet the following requirements before commissioning:

1) The bearing box and oil tank shall be cleaned and checked to be qualified before adding lubricating oil; The specification and quantity of lubricating oil shall comply with the provisions of the accompanying technical documents;

2) The steering of motor, steam turbine, tail gas turbine and other driving machines shall meet the requirements of the accompanying technical documents;

3) Turn the fan rotor without friction and scratch;

4) The lubrication system and hydraulic control system shall work normally;

5) The fan safety and interlock alarm and shutdown control system shall be subject to simulation test and shall meet the following requirements:

a) The cooling system pressure shall not be lower than the specified minimum value;

b) The oil level and pressure of lubricating oil shall not be lower than the specified minimum value;

c) The bearing temperature and temperature rise shall not be higher than the specified maximum value;

d) The effective value or peak peak value of bearing vibration speed shall not exceed the specified value;

e) Surge alarm and gas release devices shall be sensitive, correct and reliable;

f) The operating speed of the fan shall not exceed the specified maximum speed.

6) Each auxiliary equipment of the unit shall be subject to single unit test run in accordance with the provisions of the accompanying technical documents and shall be qualified;

7) The protective cover (net) of the exposed part of the fan transmission device and the inlet directly connected to the atmosphere shall be installed;

8) The air inlet pipe of the host and related equipment connected to it shall be cleaned.

(2) The test run of roots blower shall meet the following requirements:

a) Before starting, fully open the inlet and outlet valves of the blower;

b) The inlet and outlet valves shall be operated with no load under the condition of full opening, and the operation time shall not be less than 30min;

c) After the no-load operation is normal, the exhaust valve shall be gradually and slowly closed until the exhaust pressure is adjusted to the design boosting value, and the motor current shall not exceed its rated current value;

d) During the load test run, the inlet and outlet valves shall not be completely closed, and the machine shall not be overloaded. The machine shall be stopped after gradual unloading, and shall not be stopped suddenly under full load;

e) During the load test run, the blower shall run continuously for at least 2h after the temperature of each part is stabilized under the specified speed and pressure; The bearing temperature shall not exceed 95 ℃, the lubricating oil temperature shall not exceed 65 ℃, and the effective value of vibration speed shall not exceed 11.2mm/s.