SOOT BLOWER TROUBLE SHOOTING AND MAINTENANCE

SOOT BLOWER TROUBLE SHOOTING AND MAINTENANCE

Unless soot blowers are operated and maintained properly there can be lengthy and costly outages and need more expensive replacement of boiler equipment.

Preventive maintenance and check list

The following is a suggested maintenance schedule. Establish a regular maintenance program compatible with conditions at installation.

At one week intervals

Check for steam leakage in the travelling carriage gland packing. A slight amount of leakages is required and permitted. If leakage is excessive change the packing. The entire packing set should be changed at one time. Follow the instructions  for changing  the packing.

At one month intervals

Check the travelling carriage and valve of steam leakage. If steam leakage is noticed tight the gland and watch the performance during the next operation.

Check for steam leak through valve seat. A hot lance tube is the indication of steam leak through seat, if it is supported by the hissing noise of steam leakage.

Check the presence of  stop pin on cam bracket and also check the angle tracks and chains if ash building is noticed clean them.

At 6 month intervals

Check chain tension of both rotary drive and traversing drive chain. These chains should be adjusted to ride on the upper angle iron track and on the lower turned edge of the main housing. The chain should be supported and carried free from either the driver or the idler sprockets, or both, for a minimum distance 750 mm and a maximum distance of 1 meter.

Check chain tension of jack shaft and drive chain. The jack shaft drive chain should be tightened so that normal hand pressure will depress either side of the chain at the id point approximately 25 mm.

Chains subjected to corrosive atmosphere or extremely high temperature may require re-lubrication.  Lubricate chains as soon as they show signs of rust on any of the external parts. Replace any chain is badly rusted or corroded and has lubrication. Refer to lubrication section of general instructions for recommended lubricants and lubrication pressure.

Check both “stop” and “reverse” limit switches. The actuating arms should be tight and secure on the switch pivots. The pivots should be free from paints or oil so that no hindrance or binding of moment occurs. The actuating arm should be correctly adjusted so as to pass freely through the slots in the housing and be properly engaged by travelling carriage slide roller.

At one year intervals

Check gaskets at rotary gear box covers. Cap screws on covers should be tightened.

Check oil level in travelling carriage gear boxes. Add recommended lubricant if necessary.

Check oil in the reduction gear boxes on the traversing and rotary power packs. Tighten the loose bolts nuts and cap screws. Replace missing cotter pins and strings and also change motor bearing if required.

Check the threaded components with antiseiae compound so that rusting will be prevented.

Check the valve steam assembly for pitting and if pitting is severed replace the stem with new one. Apply antiseiae on the stem while assembly.

Check the mountings and hangers supports ob blower. The hang pun should be secured by cotter pins. Lock clamp washes are required to secure mounting shoulder bolts.

Test; operate each individual blower using the start button with the blowing medium of the unit under normal operating conditions. Along with the mechanical operation of each blower the blowing pressure also should be checked using pressure gauge in the operating head. The recommended blowing pressure is shown on arrangement drawings. This manual check is essential to assure that excessive blowing pressures are not incurred which would cause boiler tube wastage.3