FIELD OF THE INVENTION
The present invention relates to a method for marking process on
pressure part in boiler circuit. More particularly, it is related to
marking process of elbow part, of boiler, for different radius and
diameter without much calculation and errors.
BACKGROUND OF THE INVENTION
Background description includes information that may be helpful in
understanding the present subject matter.
For elbow manufacturing first a suitable raw material is selected
and put in a furnace at about 900 deg. C. The raw material or hot
job (hereafter job) is then taken out of the furnace for imparting
required shape and size with the help of press machine. The job
weighs about .5 ton to 1 ton. Movement of job is done using crane.
After cooling of the job it is moved to a shot blasting machine for
removal of slag present on the job surface. After cleaning it is
transferred for marking process.
The marking is an important process because, the marking is
reference for further machining process. Before initiating the
marking process, a chalk powder is applied on the surface plate and
left for some minutes for drying the chalk powder (hereafter
referred as old Method-I). Then it is required for drawing layout on

the surface plate. This marking requires skilled operator, because
this marking layout is very important reference for job marking.
The job is placed on the layout without any alignment for marking.
First the chalk powder is applied on the job surface and left for
drying. The surface table layout marking is traced on the job surface
using a scriber. Now the required marking lines are marked on the
job using the layout reference. But, this method has a disadvantage,
that after marking process of the job using the layout reference, the
chalk powder mark tends to erase and therefore same marking
process need to be repeated every time for marking of each job.
This repeatable process takes more marking time and more crane
waiting and handling time is required.
Therefore, another method (hereafter referred as old Method- II) is
required which eliminates the surface table layout marking method.
Using this method, job center line is drawn using a Vernier height
gauge. The operator needs to find for an inner axis (on boiler fitting
elbow) to mark center point and then to be punched.
The inner axis center point is transferred to an outer axis of the
elbow. This method uses arc for drawing dividing line on the job
surface. The marker calculates the outer and inner circumference
of the boiler fitting Elbow (or the job) depending upon the drawing
requirement. The marker considers job diameter, job-coordination

radius and job angles such as 90,60, 45, 30 etc. This method also
has disadvantages such as more calculation and more time which
eventually results in manual errors.
OBJECT OF THE INVENTION
It is therefore an object of the present invention to solve the
aforementioned and other drawbacks existing in earlier methods for
marking boiler fitter elbow.
Therefore, Primary object of this invention is to reduce calculation
and manual error while circumference marking of the boiler Elbow.
Yet another object of the invention to propose a marking method
for boiler elbow without layout marking.
Still another object of the invention is to propose a marking method
without using a divider arc marking process.
Yet another object of the invention is to reduce air pollution arising
at the time of removing chalk power on the job and the layout
surface.
Still another object of the invention is to reduce cycle time for Elbow
marking and machining process.

These and other objects and advantages of the present invention
will be apparent to those skilled in the art after a consideration of
the detailed description taken in conjunction with the accompanying
drawings in which a preferred form of the present invention is
illustrated.
SUMMARY OF THE INVENTION
The present invention is therefore intended to solve one or more of
the above problems by providing a method for angle marking
process on boiler fitting elbow of different sizes.
The method is initiated by clamping a laser light on a laser light
clamp set on a Vernier height gauge, clamping said Laser light unit
on a Swivel base of a height gauge clamp, rotating laser light unit
for required angle with the help of said swivel base and a bottom
block, then finally guiding the laser unit using a linear guide block
in to and fro motion while setting the radius. The laser light falls on
required half angle portion on said job surface during clockwise
movement of said guide block and cover the other half portion of
the job surface during anticlockwise direction of said guide block.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The illustrated embodiments of the subject matter will be best
understood by reference to the drawings, wherein like parts are
designated by like numerals throughout. The following description

is intended only by way of example, and simply illustrates certain
selected embodiments of apparatus that are consistent with the
subject matter as claimed herein.
Figure-1 illustrates a laser light with clamping unit fixed in Vernier
height gauge movable nips.
Figure-2 illustrates the swivel base with bottom block and guide
block.
Figure-3 illustrates the boiler fitting elbow.
Figure-4 illustrates the assemble drawing of the invention.
Figure-5 illustrates the marking process of elbow using instant
marking device.
Figure-6 illustrates the surface plate layout marking process (old
method- I).
Figure-7 illustrates the arc method marking process (old method-
II).
Figure-8 illustrates job radius length set on the guide block.
Figure-9 illustrates setting required angle on the gauge and on the
elbow.
DETAIL DESCRIPTION OF THE INVENTION
The embodiments as described below are exemplary means to
describe the present invention and may subject to various
modifications in alternate form falling within the scope of the

invention. The drawings as illustrated are for explaining details of
the present disclosure in pertinent way and could be easily
understood by person ordinarily skilled in the art.
Referring to figure 1 and 4, the device comprises of laser light (3)
with laser light clamp (1), wherein the laser light clamp used for
clamping the laser light (3) and whose other end is fixed to a Vernier
height gauge (2) with movable nips during the marking process.
This laser light unit is fixed on a swivel base (5) by using a clamp
(4). This swivel base (5) have provision to rotate 360 degrees on a
bottom block (6). The bottom block (6) top portion having 360-
degree angle graduation line for accuracy marking and also have
round pin provision for the purpose of locating swivel base (5) with
laser light unit.
Marking guide block (7) is used to guide the laser light unit to and
fro while setting of require radius distance from the inner radius of
the boiler fittings elbow.
The marking device located on a surface table in front of the inner
radius of the boiler fitting elbow. The Laser light unit is set according
to radius distance using guide block (7). The Laser light with light
clamp is set on the Vernier height gauge (2) in parallel to the Elbow
inner radius. The Laser light then passes on the center of inner
radius of the Elbow. Now the swivel base (5) with laser light unit

rotate clockwise direction to a required angle by using bottom block
(6). The laser light rays fall on required half included angle portion
on job surface. The same process is repeated on anticlockwise
direction and total angle portion is marked. Now the Laser light is
moved in the upward direction for marking top portion of the said
elbow. Thus, required angle can be marked on different sizes of the
elbow.
Referring to Figure-2, illustrates the swivel base with bottom block
and guide block. The Swivel base can rotate by 360 degrees on a
bottom block (6).
Referring to Figure-3, illustrates a Boiler fitting Elbow having an
inner radius (8) and an outer radius (9).
Referring to Figure-5, illustrates the marking process of said Boiler
fitting elbow using proposed marking device. The laser light rays
fall on Centre of the elbow inner surface (step-1). Now the swivel
base (5) with laser light unit rotate clockwise direction to a require
angle, such as 22.5 degrees, by using bottom block with graduation
line (6). The laser light (3) rays fall on the required half included
angle (22.5 degrees) portion on job surface (step-2). The same
process done on anticlockwise direction and marked total required
angle portion (fig-5 step-3).

Referring to Figure-6, illustrates the surface plate layout marking
process (old Method-I) wherein the job is placed on the layout
without any alignment for marking. First the chalk powder is applied
on the job surface and left for drying. The surface table layout
marking is traced on the job surface using a scriber. Now the
required marking lines are marked on the job using the layout
reference.
Referring to figure-7, illustrates the arc method marking process
(old method-II). Using this method, job center line is drawn using
a Vernier height gauge. The operator needs to find for an inner axis
(on boiler fitting elbow) to mark center point and then to be
punched. The inner axis center point is transferred to an outer axis
of the elbow. This method uses arc for drawing dividing line on the
job surface. The marker calculates the outer and inner
circumference of the boiler fitting Elbow (or the job) depending
upon the drawing requirement.
Referring to figure-9, for example marking of a 45-degree elbow,
an angle 22.5 degree is set on the Vernier gauge, then
corresponding to the gauge the laser light falls on the job surface
at 22.5 degrees angle and this point is noted. Same process is
followed to left side and to right side for complete center marking
of the radius of the job.

WE CLAIM:
1. A method for marking a boiler fitting during angle marking process, the
method comprising steps of:
- clamping a laser light (3) on a laser light clamp (1) set on a Vernier height
gauge (2);
- clamping said Laser light unit on a Swivel base (5) of a height gauge clamp
(4);
- rotating laser light unit for required angle with the help of said swivel base
and a bottom block (6);
- guiding the laser unit using a linear guide block (7) in to and fro motion while
setting the radius.
2. The method as claimed in claim 1, wherein the laser light falling on required
half angle portion on said job surface during clockwise movement of said
guide block and covering the other half portion of the job surface during
anticlockwise direction of said guide block.
Dated this 6th day of January, 2020