GB192457A - Improvements in apparatus for cleaning the tubes of water tube boilers - Google Patents

Abstract

192,457. Handoll, P. G. Oct. 28, 1921. Cleaning, fluid-pressure processes for.-Relates to apparatus for cleaning the tubes of water-tube boilers, of the kind employing jets of pressure fluid projected from a blower tube which is rotated by an operating worm-spindle engaging a worm-wheel on one end of the blower tube, the supply of fluid being controlled by a valve operatively connected with the actuating device of the blower tube. According to the invention, the wormspindle is adapted to have both rotary and axial movement, the latter being utilized to open the valve at the beginning of the blowing operation and close it at the end. In the, form shown, the operating spindle i is formed at one end with a spigot i<2> supported in a bearing in an L-shaped steam-tight casing c secured to the boiler front, and carries a valve d co-operating with a seat in the casing to control the flow of steam to the blower-tube a: The initial rotation of the spindle i by the operating hand-wheel results in its axial movement, the worm-wheel g acting as a nut, thus opening the valve d, until a shoulder i<5>, on the spindle i abuts against the end of a thrust bearing provided for the spindle i. Continued rotation of the spindle rotates the blower tube a through the engagement of the worm h with the worm-wheel g, until a stop g' on the wheel a comes into contact with a stop f-<5> on the casing. The position of this stop f<5> may be varied to control the angle through which the blower tube a operates. The worm-gearing g, h is disposed outside the steam casing c, steamtight glands being provided where their respective shafts pass through the casing. Thrust bearings are also provided on these shafts externally of the casing c. The bearing f<3> on the worm-wheel shaft f, which is connected to the blower-tube a through a sleeve e<1>, takes up the end thrust in the blower-tube caused by the pressure of the cleaning fluid and is adjustable by the nut f<6> to tighten the packing of a steamtight gland e in which the sleeve e<1> rotates. The Provisional Specification describes also an alternative stop device in which the angle of rotation of the blower tube is governed by a fixed pin working in a slot or groove in the worm-wheel. It also states that the steam valve instead of being actuated directly by the wormspindle may be actuated by a cam on the wormwheel operating through a lever or other mechanism.