GB2087508A

GB2087508A - Sootblowers

Info

Publication number: GB2087508A
Application number: GB8036339A
Authority: GB
Original assignee: GREENBANK ENGINEERING GROUP LT
Current assignee: GREENBANK ENGINEERING GROUP LT
Priority date: 1980-11-11
Filing date: 1980-11-11
Publication date: 1982-05-26

Abstract

A sootblower comprising a lance- supporting carriage 10 having at least one axle 11, each mounting a pair of guide rail-engaging wheels 13, a main casing supporting the lance supporting carriage 10 and a bearing arrangement constituted by a plurality of angularly spaced grooved rollers 21 within which a lance 15 is rotatably mounted. <IMAGE>

Description

SPECIFICATION Improvements in or relating to sootblowers This invention relates to lance sootblowers.

A known form of lance sootblower comprises a main casing or structure supporting a carriage to which is connected a lance having at one end nozzles. The carriage and consequently the lance are movable along the main casing or structure by a motor and suitable drive, such as a chain drive, to insert the lance into a boiler enclosure for cleaning purposes and to withdraw the lance after cleaning has been effected. For cleaning purposes, the lance is generally connected to a valvecontrolled steam or compressed air supply and is rotated or oscillated while inserted in the boiler enclosure.

With this known form of lance sootblower, the lance rotating motor and gearing are carried by the carriage which has two axles each mounting a pair of wheels or rollers for engagement with and rolling along guide rails on the main casing or structure. The motor rotates the lance through the intermediary of reduction gearing. The lance is supported adjacent the gearing within a hollow stub shaft which is, in turn, supported by a bearing arrangement comprising four angularly equispaced rollers with axes parallel to the lance axis and a pair of diametrically opposed conical thrust rollers with axes normal to the lance axis. This roller assembly provides a robust location for the lance both axially and radially within the carriage while at the same time allowing an acceptable degree of misalignment.

It is an object of the present invention to provide a lancce sootblower in which the lance driving and bearing arrangement is simplified and made more compact than the aforesaid known arrangement and consequently the overall cost of the lance sootblower reduced.

According to the present invention there is provided a sootblower comprising a lancesupporting carriage having a single axle mounting a pair of guide rail-engaging wheels, and a bearing arrangement constituted by a plurality of angularly equi-spaced grooved rollers within which a lance is rotatably mounted.

The provision of the grooved rollers provides both axial and radial bearing capacity in a simpler form than the aforesaid known form but removes the self aligning feature between the lance and the carriage. However, the necessary acceptable degree of misalignment between the lance and the carriage is provided for by the provision of the single axle.

For heavy duty purposes, if the single axle is unable to carry the radial loads it is envisaged that the carriage will be pivotally mounted on a twoaxle wheeled bogie for movement along the guide rails.

Preferably, the lance is rotated by a motor through the intermediary of a worm gearbox, whereof the axes are transversely disposed relative to the lance axis to reduce axial length.

Preferably also the lance is bolted to a hollow stub shaft having an integral gearwheel in mesh with the output shaft of the worm gearbox and also the grooved rollers. Alternatively, the lance is bolted directly to the said gearwheel.

An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is a fragmentary part-sectional view of a lance sootblower showing a carriage and bearing arrangement according to the invention; Fig. 2 is a corresponding fragmentary partsectional plan view; and Fig. 3 is an end view.

The lance sootblower will not be described in detail since its construction is known to those skilled in the art save for the carriage and bearing arrangement which is the subject of the present invention.

In accordance with this invention, the carriage 10 of the lance sootblower has a single axle 11 rotatable in rolling bearings 12 and mounting at each end a wheel 13 adapted to roll along a guide rail 14 extending the length of the main casing of the sootblower.

The lance 1 5 of the sootblower is bolted as indicated at 16 to a hollow stub shaft 17 which has an integral large diameter gearwheel 18. The latter meshes with a relatively small diameter output gearwheel 1 9 of a transversely-disposed motor and worm gear assembly 20 carried by the carriage 10.

The gearwheel 18 is also in mesh with four equi-angularly spaced grooved rollers 21 rotatably mounted through the intermediary of roller bearings 22 on axles 23 mounted on the carriage 1 0.

The grooved rollers 21 provide a simple axial and radial bearing arrangement which prevents any misalignment between the carriage 10 and the lance 1 5. The necessary acceptable misalignment during movements of the lance 1 5 into and out of a boiler enclosure is provided for by the single axle 11.

The carriage and bearing arrangement described above is more compact, simpler and more economic to produce than existing arrangements.

The lance sootblower according to the invention operates in the conventional well known manner.

1. A sootblower comprising a lance, a lance supporting carriage having at least one axle, each mounting a pair of guide rail engaging wheels, a main casing supporting the lance supporting carriage and a bearing arrangement within which a lance is rotatably mounted, characterised in that the bearing arrangement comprises a plurality of angularly spaced grooved rollers.

2. A sootblower comprising a lance, a lance supporting carriage having at least one axle, each mounting a pair of guide rail engaging wheels, a main casing supporting the lance supporting

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Improvements in or relating to sootblowers This invention relates to lance sootblowers. A known form of lance sootblower comprises a main casing or structure supporting a carriage to which is connected a lance having at one end nozzles. The carriage and consequently the lance are movable along the main casing or structure by a motor and suitable drive, such as a chain drive, to insert the lance into a boiler enclosure for cleaning purposes and to withdraw the lance after cleaning has been effected. For cleaning purposes, the lance is generally connected to a valvecontrolled steam or compressed air supply and is rotated or oscillated while inserted in the boiler enclosure. With this known form of lance sootblower, the lance rotating motor and gearing are carried by the carriage which has two axles each mounting a pair of wheels or rollers for engagement with and rolling along guide rails on the main casing or structure. The motor rotates the lance through the intermediary of reduction gearing. The lance is supported adjacent the gearing within a hollow stub shaft which is, in turn, supported by a bearing arrangement comprising four angularly equispaced rollers with axes parallel to the lance axis and a pair of diametrically opposed conical thrust rollers with axes normal to the lance axis. This roller assembly provides a robust location for the lance both axially and radially within the carriage while at the same time allowing an acceptable degree of misalignment. It is an object of the present invention to provide a lancce sootblower in which the lance driving and bearing arrangement is simplified and made more compact than the aforesaid known arrangement and consequently the overall cost of the lance sootblower reduced. According to the present invention there is provided a sootblower comprising a lancesupporting carriage having a single axle mounting a pair of guide rail-engaging wheels, and a bearing arrangement constituted by a plurality of angularly equi-spaced grooved rollers within which a lance is rotatably mounted. The provision of the grooved rollers provides both axial and radial bearing capacity in a simpler form than the aforesaid known form but removes the self aligning feature between the lance and the carriage. However, the necessary acceptable degree of misalignment between the lance and the carriage is provided for by the provision of the single axle. For heavy duty purposes, if the single axle is unable to carry the radial loads it is envisaged that the carriage will be pivotally mounted on a twoaxle wheeled bogie for movement along the guide rails. Preferably, the lance is rotated by a motor through the intermediary of a worm gearbox, whereof the axes are transversely disposed relative to the lance axis to reduce axial length. Preferably also the lance is bolted to a hollow stub shaft having an integral gearwheel in mesh with the output shaft of the worm gearbox and also the grooved rollers. Alternatively, the lance is bolted directly to the said gearwheel. An embodiment of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Fig. 1 is a fragmentary part-sectional view of a lance sootblower showing a carriage and bearing arrangement according to the invention; Fig. 2 is a corresponding fragmentary partsectional plan view; and Fig. 3 is an end view. The lance sootblower will not be described in detail since its construction is known to those skilled in the art save for the carriage and bearing arrangement which is the subject of the present invention. In accordance with this invention, the carriage 10 of the lance sootblower has a single axle 11 rotatable in rolling bearings 12 and mounting at each end a wheel 13 adapted to roll along a guide rail 14 extending the length of the main casing of the sootblower. The lance 1 5 of the sootblower is bolted as indicated at 16 to a hollow stub shaft 17 which has an integral large diameter gearwheel 18. The latter meshes with a relatively small diameter output gearwheel 1 9 of a transversely-disposed motor and worm gear assembly 20 carried by the carriage 10. The gearwheel 18 is also in mesh with four equi-angularly spaced grooved rollers 21 rotatably mounted through the intermediary of roller bearings 22 on axles 23 mounted on the carriage 1 0. The grooved rollers 21 provide a simple axial and radial bearing arrangement which prevents any misalignment between the carriage 10 and the lance 1 5. The necessary acceptable misalignment during movements of the lance 1 5 into and out of a boiler enclosure is provided for by the single axle 11. The carriage and bearing arrangement described above is more compact, simpler and more economic to produce than existing arrangements. The lance sootblower according to the invention operates in the conventional well known manner. CLAIMS

2. A sootblower comprising a lance, a lance supporting carriage having at least one axle, each mounting a pair of guide rail engaging wheels, a main casing supporting the lance supporting carriage and a bearing arrangement within which the lance is rotatably mounted, characterised in that the bearing arrangement comprises a plurality of angularly spaced grooved rollers with axes parallel to the lance axis and a lance support member to which the lance is secured the lance support member engaging in the grooves of the said plurality of angularly spaced grooved rollers and being rotatable therein.

3. A sootblower according to Claim 1 or 2 characterised in that the carriage comprises a single axle, in order to achieve an acceptable degree of misalignment between the lance and the main casing.

4. A sootblower according to Claim 1 or 2 characterised in that the carriage is pivotally mounted on a wheeled bogie comprising at least two axles in order to achieve acceptable degree of misalignment between the lance and the main casing.

5. A sootblower according to any preceding claim, characterised in that the lance is rotated by a motor through the intermediary of a worm gearbox, whereof the axes are transversely disposed relative to the lance axis to reduce axial length.

6. A sootblower according to claim 5, wherein the lance is bolted to a hollow stub shaft having an integral gearwheel in mesh with the output shaft of the worm gearbox and also the grooved rollers.

7. A sootblower according to claim 5, wherein the lance is bolted directly to an integral gearwheel in mesh with the output shaft of the worm gearbox and also the grooved rollers.