Improvements in Apparatus for Drilling Boiler Shells or Drums.
Year: 1894

page_text: Date of Application, 7th June, 1894
Complete Specification Left, 7th Mar., 1895-Accepted, 13th Apr.. 1895
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Drilling Boiler Shells or Drums.
We, BABCOCK & WILCOX, LTD. of 147 Queen Victoria Street, in the City of
London, Steam Boiler Manufacturers, and OSCAR HARMER, Engineer at Babcock
& Wilcox, Ltd. 21, Bothwell Street, in the City of Glasgow, do hereby declare
the nature of this invention to be as follows:-
This invention has for its object the construction of a machine for drilling out
the rivet holes in the plates composing a boiler shell or drum both for the longi-
tudinal and circumferential rows of rivets the shell or drum being operated on
whilst the plates are tacked together by bolts or otherwise or supported horizontally
in the machine.
The improved apparatus comprises a long bed-plate upon, which is mounted at
one or both ends a framing carrying a chuck after the fashion of a turning lathe
and by means of which the end or ends of the boiler shell or drum is or are secured,
whilst its weight is supported upon rollers carried by slides mounted transversely in
pairs on the bed-plate. The slides are operated by right and left-handed screws or
like means to separate the supporting rollers and bring them closer together in
order to adapt them for carrying various sizes of shells or drums concentrically
with the chuck or chucks.
The drill heads, of which there are in general as many as there are circum-
ferential seams in the shell or drum so that the several rows of holes may be drilled
out simultaneously, are carried on slides adapted to be traversed longitudinally
upon beds fitted to move transversely over the bed-plate and also capable of being
separated longitudinally more or less by means of revolving nuts and screws or
other means the several drill heads being also fitted so that they may be separated
by means of right and left-handed or differential screws which move the heads
independently on the slides. The drill spindles are operated by mitre or other
gearing from a shaft carried the whole length of the machine and driven by any
suitable gearing the entire series of drills operating at once either on the longi-
tudinal or on the circumferential seams of the shell or drum. The spacing or pitch
of the rivet holes is obtained by the use of dividing mechanism in each case the
several drill heads being traversed to the required distance after each drilling
operation in drilling the longitudinal seams, and the shell or drum being turned
with the chuck or chucks in operating on the circumferential seams. The dividing
mechanism may consist of a hand wheel or lever on a worm shaft acting through a
worm wheel and change wheels on the spindle carrying the chuck, and a hand
wheel acting through like gearing or directly on the traversing screw for the slides,
a disc and pointer or marker being provided in each case to indicate to the operator
the proper extent of movement.
The chuck for holding the drum end is provided with four or more jaws, which
may hold the shell either externally or internally provided in the latter case the
drum end be removed. The jaws are adjustable radially by screws as in a lathe
chuck but instead of directly gripping the drum they are each fitted with a pivoted
jaw piece arranged to bear on the drum and to be secured by a wedge piece or like
means which on being driven out permits of the pivoted jaw being tilted out of the
way. By this means whilst the drum or shell may be securely held to the chuck
by the major number of the jaws each one may in turn be removed to permit of
drilling out the hole or holes underneath the jaws.
For the purpose of operating on the end plates or angle irons on the end plates

page_text: of boiler shells having flat ends a separate bed carrying a drill head set to drill at
right angles to the main row of drills may be provided the said drill head being
driven by mitre or other gearing from the main driving spindle and being arranged
to operate either independently or simultaneously with the drills when operating on
the circumferential seams.
The drill spindles are each supported near the cutting end by means of a bracket
with a guide bush whereby the drill is kept axially true with the spindle.
Dated this 6th day of June 1894.
CRUIKSHANK & FAIRWEATHER,
62, St. Vincent Street, Glasgow, Agents.."
· Improvements in Apparatus for Drilling Boiler Shells or Drums.
We, BABCOCK & WILCOX (LIMITED), of 147 Queen Victoria Street, in the
City of London, Steam Boiler Manufacturers, and OSCAR HARMER, Engineer at
Babcock & Wilcox (Limited) 21 Bothwell Street, in the City of Glasgow, do
hereby declare the nature of this invention and in what manner the same is to
be performed, to be particularly described and ascertained in and by the following
statement: :-
This invention has for its object the construction of a machine for drilling out
the rivet holes in the plates composing a boiler shell or drum both for the longi-
tudinal and circumferential rows of rivets, the shell or drum being operated on
whilst the plates are tacked together by bolts or otherwise or supported horizontally
in the machine.
The invention is illustrated by the accompanying drawings.
Figure 1 is a longitudinal elevation partly in section, Figure 2 an end elevation
also partly in section with the spacing wheels removed, and Figure 3 a plan.
Figure 4 is a view similar to Figure 2 but showing the position of the spacing
wheels,
Figure 5 is a section on the line -y, Figure 4, and
Figure 6 is a detail of one of the drill spindles.
Figure 7 is a detail of the mechanism for withdrawing any drill from the work
when it is desired to allow that drill to remain idle, and
Figure 8 is a view of a modification of a chuck.
The improved apparatus comprises a long bed-plate A upon which is mounted at
one or both ends a framing B carrying a chuck C after the fashion of a turning
lathe and by means of which the end or ends of the boiler shell or drum D, shown
in dotted lines at Figure 1, is or are secured.
In the example shown only one chuck is used. The boiler shell D is surrounded
at various points in its length by channel rings d carried upon rollers e journalled
in brackets e carried by slides E and mounted transversely in pairs on the bed-
plate A thus supporting the weight of the boiler shell. The slides E are operated
by right and left handed screws e or like means by the application of a hand-key
or otherwise to separate the supporting rollers e and bring them closer together in
order to adapt them for carrying various sizes of shells or drums concentrically
with the chuck or chucks.
The drill heads F, of which there are in general as many as there are circum-
ferential seams in the shell or drum D so that the several rows of holes may be
drilled out simultaneously, are carried on travelling tables G adapted to be
traversed longitudinally upon a bed H fitted to move transversely over slides hon
the bed-plate A. The tables G are capable of movement together in either
direction or of being separated longitudinally more or less, by means of revolving

page_text: nuts and screws or other means. The travelling tables G are moved in unison by
means of a worm screw I carried in hearings at either end of the bed H, said
worm I acting on a worm wheel I' which embraces it to move the wheel I¹ in either
direction. This worm wheel I' besides embracing the worm 1 is carried in a
bracket secured to the underside of each of the travelling tables G and said worm
wheel being prevented from rotating by its engagement with a vertical worm 12
thus traverses the tables together in either direction according to the direction of.
rotation of the worm screw I.
The several drill heads F are fitted so that they may be separated by means of
right and left handed or differential screws or other means, which move the heads
independently of the tables G.
In the present instance the tops of the tables G have teeth formed on them
with which spur pinions g', on the bottom of vertical spindles g² secured in the drill
heads F, gear, and which vertical spindles g² are turned by means of keys fitted
over the upper ends to separate or bring together said heads independently of the
power gearing.
When it is desired to traverse the tables G independently of each other the.
mechanism shown at J with which each table is provided is put in motion. This
mechanism J consists of a belt pulley; driven from a belt pulley j' on the main
driving shaft K. On the same shaft with the pulley is a spur wheel gearing
with a spur wheel on the shaft. Loose on this shaft are two bevel wheels j*
and either of which is set in motion by an ordinary cone clutch actuated by a
hand lever. Both of these bevel wheels gear with a bevel on the upper end of
a vertical shaft, and on the lower end of this shaft the worm 12 which formerly
acted to prevent the worm wheel I' from revolving is keyed, and by its action on
the worm wheel I' revolves said wheel on the worm screw I thus separating the
tables G.
The drill spindles are operated by mitre or other gearing 1, 2, from the main
driving shaft K said shaft being carried the whole length of the machine and
driven by any suitable gearing. The bevel gears are carried by brackets 1³
which surround the driving shaft K, from the drill heads F, said bevel gears being
keyed in a longitudinal slot, which allows of their being carried in either direction
in unison with the drill head.
As shown at Figure 6 the drill spindles are each surrounded by a sleeve 14
whose upper side is formed as a rack said rack being placed between two
collars on the drill spindle so that when the rack is acted on by the pinion, in
the head F, the Qrill spindle is fed forward to, and during, the boring operation.
A longitudinal key slot 3 is made in said spindle in which a key secured in a
sleeve surrounding the spindle I acts to revolve it whilst permitting of its being
fed forward.
When any of the series of drills are not required these may be so disconnected as
to prevent their being fed forward towards the work. For this purpose the
pinion is keyed as shown at Figure 7 upon the sleeve of a hand wheel which is
loose upon a longitudinal shaft M passing through the drill heads F. Keyed on
this shaft M is a disc having bolts and nuts passed through it said bolts
having on their other ends heads 122 which enter an inclined circular groove 12 in
the hand wheel to which wheel the disc is clutched by tightening the outs 1.
When the nuts are loosened and the hand wheel thereby freed from engagement
with the disc, the drill spindle is no longer fed forward but may be retracted if
desired to bring it clear of the work.
Besides being adapted to retract any one of the drills clear of the work the
drill spindle can be so disconnected that it will no longer be revolved. For this
purpose the sleeve 115 is provided with two circumferential grooves 117, 118, into
which a pin screwed into the hearing of the sleeve 1, enters, so that when the
pin is in the groove the bevel wheel is in gear with the bevel 2 and
consequently the drill spindle is revolved; but when the sleeve is brought forward
so that the pin is entered into the groove the bevel wheel is withdrawn from

page_text: engagement with the bevel 1. Ordinarily the entire series of drills operate at once
either on the longitudinal seam or on the circumferential seams of the boiler shell
or drum D.
The chuck C which consists of two arms placed diametrically opposite each
other, for holding the drum end, (either externally or internally in which latter
case the end of the drum is removed), is provided with two pieces c.
These
pieces c are slotted for the reception_of_bolts c' which pass through holes in the
_boiler shell and chuck the work.
The pieces c are each secured on a sliding piece adjustable transversely by
means of a screw c³ journalled in a second sliding piece which is in turn moved
radially on its chuck arm C by a screw c journalled therein, these screws c³, c³,
being turned by keys as in a lathe chuck.
As an alternative to this method of chucking the boiler shell D, and as
illustrated by the modification Figure 8 the chuck C for holding the drum end is
provided with four or more jaws c. These jaws are also adjustable radially as in
the former case but instead of directly gripping the drum D they are each fitted
with a pivoted jaw piece. c arranged to bear on the drum D, and secured by a
wedge piece or like means, which on being driven out permits of the pivoted jaw c
being tilted out of the way. By this means whilst the drum or shell D may be
securely held to the chuck by the major number of the jaws each one may in turn
be removed to permit of drilling out the hole or holes underneath the jaws.
For the purpose of operating on the end plates or angle irons on the end plates
of boiler shells having flat ends, a separate bed H' carrying a sliding table G¹ upon
which are secured drills 20 set to drill at right angles to the main row of drills,
may be provided, the said drills 120 being driven by mitre or other gearing 95, 96,
93, 9, from the main driving shaft K. The bevel wheels g, g³, are carried on the
shafts K, K', in a manner similar to that described with reference to the bevel
wheels 1.
A worm screw 13 worm wheel I and vertical worm Is are provided in conjunction
with the end table G' similar to those for actuating the tables G. This worm
screw Is has at one end a bevel wheel gearing with a second bevel wheel keyed in
a longitudinal slot 2 in the worm screw I the latter bevel being carried in a bracket
from the bed H¹ and surrounding the worm screw I. The drills are arranged to
operate either independently or simultaneously with the drills 14 when these are
operating on the circumferential seams. The bevel wheel on the worm screw I³ is
arranged in a manner similar to the bevel wheels on the drill spindle so as to
allow it to be disengaged when desired.
The drill spindles 7 are each supported near their cutting end by means of a
bracket N with a guide bush whereby the drill is kept axially true with the
spindle.
The spacing or pitch of the rivet holes is obtained by the use of dividing
mechanism, in each case, the several drill heads F being traversed to the required
distance after each drilling operation in drilling the longitudinal seam and the shell
or drum being turned by the chuck or chucks in operating on the circumferential
seam. The dividing mechanism for the circumferential seams may consist of a
lever or hand wheel O on a shaft o acting through change wheels o¹, o², o³, and
through a worm of to a worm wheel o secured on the spindle of carrying the
chuck C.
For spacing the longitudinal seams a hand wheel P acts through like gearing or
directly on the traversing screw I for traversing the sliding tables G, a disc and
pointer or marker being provided in each case to indicate to the operator the proper
extent of movement.
By preference when spacing the longitudinal seams change wheels are used
which do the spacing automatically and dispense with the use of the hand wheel P.
For this purpose the change wheels p, p, p², p³, p², pa on spindles p², p³ and p³ are
provided which act upon each other in a manner hereinafter described to traverse
the drill head F the required distance.

page_text: The operation of the machine is as follows-The bed H, and with it the tables G
and drill heads F, is advanced on the slides until the drills are within a short
distance from the work, by turning a hand wheel Q on a longitudinal shaft Q'..
On this shaft Q bevel wheels are keyed which gear with bevels q' on screw
spindles q² carried in the slides h said screw spindles being surrounded by nuts h¹ on
the bottom of the bed H. The main driving shaft K which is provided with fast
and loose pulleys, is then started and communicates motion to a spur pinion k,.
gearing with a pinion, which in turn gears with a pinion 4, both of these
pinions, 2, being carried on brackets from the bed H. On the same spindle as.
the pinion is a worm gearing with a worm wheel on a shaft on which is a.
worm which communicates motion to a worm wheel on the longitudinal
shaft M which passes through the drill heads F and by means of the pinions
acting on the racks feeds the drills forward to the work. For the purpose of
feeding forward the drills to the work before the actual boring commences more
quickly than by means of the gearing, a hand wheel k is provided on the sleeve of
which the worm is keyed. The hand wheel is loose upon the shaft * and is
turned with it by means of a pawl pivoted on the hand wheel which engages a
ratchet wheel A keyed on the shaft. By throwing the pawls 4 out of engage-
ment with the wheel 10 the hand wheel , and with it the worm 6 and through
these the worm wheel k', and pinion on the shaft M can be turned to advance the
drills to the work independently of the power gearing.
During the advancement of the drill spindles the drills + are revolved by the
bevel gearing, P².
On the main driving shaft K a spur pinion gears with a like pinion 12 on a
spindle carried by a bracket k¹³ from the bed H. On the same spindle with the
pinion is a bevel wheel k¹ gearing with a bevel wheel on a shaft 16 at whose
opposite end is a second bevel wheel k" gearing with a bevel 18 on a vertical
shaft k19. On the lower end of this shaft is a bevel wheel which gears with
either of two bevels 21, 22, loose upon the horizontal spindle p' by means of a cone
clutch keyed on the spindle p and actuated by a hand lever 3 when the
tables G' have to be moved to drill the next hole. On the spindle p* is keyed a
spur pinion 2 called the main driver in the spacing mechanism for the longitudinal
seams which communicates motion to a spur wheel 25 keyed on the sleeve of a hand
wheel P loose upon a stud or spindle p carried from the bed H. On the sleeve of
the spur wheel is keyed the spur wheel p which gears with the spur wheel pl
loose upon the spindle
To this wheel p' is fixed the spur wheel p which gears with the spar wheel p³.
loose on the sleeve of the hand wheel P. The wheel p³ acts on a spur wheel p' to
which is keyed a spur wheel p, the spur wheel p' revolving on a stud p on the
table H. This wheel pacts on a pinion p³ on the worm screw I to traverse the
tables G together in either direction according to which of the bevels k21, 22,
the clutch 2 is in engagement with. The spur wheel has a stud fixed in its side
which comes opposite a pointer projecting from the bed H and indicates to the
operator that the required travel has been given.
This spacing can be accomplished by means of the hand wheel P on the stud p³
when the necessary change wheels cannot be obtained. For this purpose the
wheel is keyed to the sleeve of the hand wheel P, and when it is necessary to do
the spacing by this means the cone clutch 26 is withdrawn from engagement with
either of the bevels 21, 1.29
When spacing the circumferential holes the hand wheel O is turned until a mark
on it comes opposite a pointer thus indicating to the operator that the requisite
turn has been made.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is-
1. The combination of parts constituting the improved apparatus for drilling

page_text: boiler shells or drums substantially as described with reference to the annexed
drawings.
2. In apparatus for drilling boiler shells or drums the mechanism for spacing the
holes on the circumferential seams consisting of band wheel O spur gearing o¹, o², 0³
worm o' and worm wheel of the latter being keyed upon the spindle of the chuck P
and operating to turn the boiler shell or drum the requisite distance substantially
as described with reference to the annexed drawings.
3. In apparatus for drilling boiler shells or drums the mechanism for spacing the
holes on the longitudinal seams, consisting of the tables G traversed together by
meaus of the worm screw I and worm wheel 11 through gearing from the main
driving shaft and change wheels-to-a-spur wheel on the end of the worm screw I,
or independently of each other by means of the mechanism J and worm I* acting
on the worm wheel. I substantially as described with reference to the annexed
drawings.
4. In apparatus for drilling boiler shells or drums a chuck having pivoted jaws
which permits of each jaw being in turn tilted out of the way in order to drill the
hole or holes underneath the jaw substantially as described with reference to the
annexed drawings.
5. In apparatus for drilling boiler shells or drums the provision of a bracket N
having a guide bush to maintain the drill axially true with the spindle substantially
as described with reference to the annexed drawings.
Dated this 6th day of March 1895.
CRUIKSHANK & FAIRWEATHER,
62, St. Vincent Street, Glasgow, Agents.