LONG RETRACTABLE SOOT BLOWER
The LRD-IIE model soot blower is a boiler cleaning device in which a rotating lance extends into and retracts form the boiler to make sure that the cleaning medium steam which is directed through the nozzles removes the deposits from tube surfaces.
The lance is attached to a carriage housing which runs on tracks inside the blower housing. The carriage and lance are moved by means of traversing chain operated by an electric power pack. Rotary motion is applied to the lance through the travelling carriage by a second chain driven by a separate electric power pack. Control movement is by a stop limit switch and a reverse limit switch.
The unit can be supplied with different traversing and rotating speeds. Standard traversing speeds are in increments form 1.25to 3.65m per minute. Standard rotating speeds are available in various increments from 4.25 rpm to 7.75rpm. These speed variations are accomplished by changing the power pack and jack shaft drive sprockets. Other speeds are possible for special application by the use of special sprockets.
Flow of blowing medium through the retractable soot blower is controlled by the valve mounted at the rear end of the blower., The feed pipe is attached to the outlet of this value head. This feed pipe passes through packing gland in the travelling carriage and lies inside the Lance tube extending to almost the entire length of the blower. The wheels on the travelling carriage run to tracks welded to the inside of the blower housing. Slideways motion is limited by a roller on each side of the carriage which uses the housing side as guides.
The ends of traversing chain are connected to each end of the carriage. The rotary chain is continuous. It passes over sprockets on the carriage and causes rotation through a gear train. The lance is flanged to the carriage and supported on the boiler end by bearing and yoke plate. The electric gear box on the right side of for traversing and the electric gear box on the left side is for rotation when viewed from rear end of the blower.
Motion is transmitted form the gear boxes to jack shafts on each side of the blower. Tension on the internal chains is adjusted by adjusting the screws on chain tightness which hold the idler sprockets on the outboard end of the unit. The housing completely covers the blower expect the traversing and rotating gear boxes. The housing is open at the bottom expect the traversing and rotating gear boxes. The housing is open at the bottom expect for the tie bars an intervals. A section of the top of the housing near the rear end of the blower is cut away to allow access to the travelling carriage. The access areas have removable cover. A short section of the track at the rear is removable to permit removing the travelling carriage for major maintenance.
The soot blow valve head is operated by trip pin on the top of the travelling carriage which engages a trip cam through the trip rod linkage and valve lever causes the head valve to open or close. The stroke of the head valve is governed by the length of the trip rod. To change the valve stroke, loosen the join nuts where it screws into the rod connection and turn the rod. One end of the rod has a right hand thread, the other end in left hand. When the desired length is attained, tight the join nuts. The spring on the trip rod should be adjusted to eliminate all looseness in the assembly.
START UP CHECK
- Check the blower numbers and their locations
- Check the chain tensions
- Check the position of the valve opening cam.
- Check all the cable connections.
- Check lubrication in the gear box
- Check for free manual movement
- Check the lance or boiler tube clearances