FIELD OF INVENTION
The present invention relates to an automated apparatus and a
method of chamfering, de-burring and measurement of large volume holes for
different sizes of heat exchanger and condenser plates.
BACKGROUND OF INVENTION
In the heat exchanger or condenser, particularly for steam
generators of pressurized water stations, large plates are provided with large
volume holes (thousands of holes) for fixing and supporting the tubes bundles.
These holes are drilled using mechanical means such as single-spindle or multi-
spindle drilling machines. The holes, produced by mechanical machining process
have sharp corners or burrs formed by metal which is pushed back by the
machining operation. These holes are critical for further assembly of tubes and
hence required to be de-burred or chamfered for easier insertion of the tubes.
The diameter of the holes, pitch between the holes, circularity and straightness
of holes needs to be within the assembly tolerances for correct and easier of
insertion of tubes. Hence there is necessity of measurement of the hole
parameters to identify incorrect holes.

In the known manual method of chamfering, de-burring and
inspection of the large volume holes of the heat exchanger or condenser plates,
the holes are chamfered and de-burred using a hand-held chamfering or de-
burring device. The measurement is carried out by 'go'- 'no-go' gauge. This
manual method is inaccurate and cumbersome leading to large cycle time of the
component inspection.
Some apparatus and methods have been previously employed for
chamfering, de-burring and measurement of the holes but none of the apparatus
or method have been employed for large volume hole chamfering, deburring and
measurement of holes as proposed in current invention.
In one method, (Refer Patent No. EP 0032102), a device for fettling
and chamfering has been proposed using at least one abrasive brush rotating
about its axis of symmetry.
In another method (Refer Patent No. US 484245), a de-burring drill
bit having a shank, an elongated shaft, a drill bit head having forward drilling
surfaces formed in the head and rearward drilling surfaces formed behind the
said forward drilling surfaces, whereby drilling and de-burring operation can be
performed in single operation.

Another invention (Refer Patent No. US 6019555), provides an
improved de-burring tool which can simultaneously chamfer a hole and has
longer useful life and which may be operated by a machine.
In Patent No. US 4235110, an apparatus and a method has been
proposed for measuring crevice gap clearance between the tubes and tube
supports in a heat exchanger.
In another patent (Refer US patent US 2012/0288336 Al), provides
a system comprising a drilling machine; a capacitive probe; and a probe
deployment system, mounted to the machine, for moving the capacitive probe
inside a hole drilled by the machine to measure the drilled hole at different
depths.
The present invention relates to an automated apparatus and a
method for chamfering, de-burring and measurement of the large volume holes
for different sizes of heat-exchanger or a condenser plates with varying
diameters and number of holes.
OBJECTS OF THE INVENTION
It is therefore, the object of the present invention to propose an
automated apparatus and a method for chamfering, de-burring and
measurement of the large volume holes for different sizes heat-exchanger and

condenser plates having varying hole diameter and number of holes which is
capable of decreasing the cycle time and improve the accuracy of chamfering,
de-burring and hole measurement process.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
According to the invention,
Fig.1 - Shows a top view of the automated apparatus showing a
condenser plate having large number of holes.
Fig.2 - Shows a side view of the automated apparatus showing a
condenser plate having large number of holes.
Fig.3 - Shows a front view of the automated apparatus showing a
condenser plate having number of holes.
Fig.4 - Shows a side view of the automated apparatus wherein the Y-axis
along with two Z-axes has traveled from initial position A to end
position B.
Fig.5 - Shows a top view of the automated apparatus wherein the Y-axis
along with two Z-axes has traveled from initial position A to end
position B.

Fig.6 - Shows a front view of the automated apparatus wherein one of the
Z-axes has extended through the hole in the condenser plate.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE
INVENTION
In an embodiment of the present invention, the condenser plate is
placed on the support blocks 8 which are firmly secured at the desired places in
grooves in the T-slotted plate 7. At the start of the cycle of the proposed
automated apparatus, Zl-axis 3 carrying a rotating spindle 10 with chamfering or
de-burring tool 11 moves from a programmed home position to a programmed
position on top of first hole. The Zl-axis 3 then, through a programmed motion,
extends down to chamfer or de-burr the hole by the rotating the chamfering or
de-burring tool 11. The Zl-axis 3 has capability to extend such that the
chamfering or de-burring tool 11 can travel below the bottom surface of the
condenser plate 6. The top surface of hole is chamfered or de-burred while the
chamfering or de-burring tool 11 is traveling down and the bottom surface of
hole is chamfered or de-burred while the chamfering or de-burring tool 11 is
traveling up. The chamfering or de-burring . operation is repeated for
programmed second and subsequent holes till all the holes of the condenser
plate 6 are chamfered or de-burred. After the chamfering to de-burring operation

of the last hole is finished, the apparatus travels back to a programmed home
position.
Also in the embodiment of the present invention, for the
measurement of hole paramets, at the start of the cycle of the proposed
automated apparatus, Z2-axis 4 on which measurement probe 9 is mounted,
moves from a programmed home position to a programmed position on top of
first hole. The Z2-axis 4, through a programmed motion, extends down and
positions the measurement probe 9 at a programmed measuring position at a
desired depth in the first hole. The X axis 1 and Y axis 2 of the apparatus moves
to a first point till the measurement probe 9 touches side of the hole and triggers
a signal to the apparatus' programmable controller. It then moves to a
programmed second point that is diametrically opposite to first point till the
measurement probe 9 touches the wall of the hole and triggers a signal to the
apparatus' programmable controller. The measurement probe 9 further moves to
a programmed third point diametrically perpendicular the line from first and
second point till it touches the wall of the hole and triggers a signal to apparatus'
programmable controller. Then, it moves to a programmed fourth point that is
diametrically opposite to the third point till it touches the wall of the hole and
triggers a signal to apparatus' programmable controller. The apparatus'

programmable controller stores the positional data of all four points for further
calculations. This operation is repeated for second point of the same hole at a
programmed second depth level. The apparatus' programmable controller stores
the positional data of all four points for further calculations. Based on the
measurement data for eight points of the hole, the apparatus' programmable
controller calculates the diameter of holes at two desired depth levels, pitch
between the holes, circularity and cylindricity of the holes. The measurement
operation is repeated for programmed second and subsequent holes till all the
holes of the condenser plate 6 are measured. After the measurement operation
of last hole is finished, the axes 1,2,3,4 travel back to a programmed home
position.
As shown in Fig.1 a top view of the automated apparatus showing
a condenser plate having large number of holes mounted on a T-slotted bed
plate by supports, a gantry consisting of two horizontal X-axis rails, one
horizontal Y-axis rail mounted on X-axis rails and two vertical Z-axes rails
mounted on Y-axis and supporting legs.
In the side view of Fig.2, the automated apparatus is shown with a
condenser plate having large number of holes mounted on a T-slotted bed plate
by height blocks, a gantry consisting of two horizontal x-axis rails, one horizontal

Y-axis rail mounted on X-axis rails and two vertical Z-axes r5ail mounted on Y-
axis, supporting legs.
In figure 3, the automated apparatus showing a condenser plate
having large number of holes mounted on a T-slotted bed plate by height blocks,
a gantry consisting of two horizontal x-axis rail, one horizontal Y-axis rail
mounted on X-axis rails and two vertical Z-axes rails mounted on Y-axis, a
chamfering tool mounted on one Z-axis rail and measurement probe mounted on
other Z-axis rail and supporting legs.
In Fig.4, the automated apparatus wherein the Y-axis along with
two Z-axes has traveled from initial position A to end position B. The condenser
plate and T-slotted bed plate has not been shown for clarity.
Fig.5 shows the automated apparatus wherein the Y-axis along
with two Z-axes has travelled from initial position A to end position B. The
condenser plate and T-slotted bed plate has not been shown for clarity.
The present invention relates to an automated apparatus and a
programmable method for chamfering, de-burring and measurement of the large
volume holes of different sizes of heat-exchanger or condenser plates 6 with
varying hole diameter and number of holes to decrease the cycle time and
improve the accuracy of chamfering, de-burring and hole measurement process.

The embodiment of the present invention, the apparatus consists
of two horizontal X-axis rails 1, one horizontal Y-axis rail 2 mounted on X-axis
rails 1 and two vertical Z-axes (Z1 axis and Z2 axis) rails 3, 4 mounted on Y-axis
2, supporting structure consisting of required legs 5 and a programmable
controller for motion control of X, Y and Z axes and storage and post-processing
of measured data. The Y-axis 2, guided by linear rails mounted on X-axis beams,
has the ability of traveling forward and backward on X-axis rails 1 using servo-
motor driven rack & pinion or ball-screw & box-nut arrangement. Two Z-axes 3,
4 also supported by guided by linear rails, can extend or retract with servo-motor
using rack and pinion or ball-screw and box-nut arrangement or a pneumatically
driven cylinder. All the motions of the X, Y, and Z axes 1,2,3,4 are programmable
and controlled by a four-axis programmable controller.
The X-axis 1, Y-axis 2 and both Z-axes 3, 4 have a rotary encoder
or linear scales for accurate position feedback to the programmable controller.
The Z1-axis 3 has an arrangement for mounting a rotating spindle
10 having a front and back chamfering or de-burring tool 11 to carry out
chamfering or de-burring on both sides i.e. top and bottom of condenser or heat
exchanger plate holes. The Z2-axis 4 has an arrangement for mounting a probe
9 for measurement of hole parameters.

WE CLAIM
1. An automated apparatus for chamfering/de-burring and measurement of
large volume of holes for different sizes of heat exchanger and condenser,
plates the said apparatus comprising;
two horizontal X-axis rail (1);
one horizontal Y-axis rail (2) mounted on X-axis rails (1);
two vertical Z-axes (Z1 and Z2 axis) rails (3, 4) mounted on Y-axis
(2) when Z1-axis (3) carrying a rotating spindle (10) having
chamfering/de-burring tool (11) and Z2-axis (4) carrying a measurement
probe (9) wherein the Zl-axis (3) can extend such that the chamfering or
de-burring tool (11) can travel below the bottom surface of the condenser
plate (6) for chamfering or de-burring of the holes;
a programmable controller, for motion control of X, Y and Z axes;
a supporting structure having support blocks (8) disposed in the T-
slotted plate (7) and supporting legs (5);
wherein the chamfering tool (11) is disposed for chamfering or de-
burring all the holes and the measurement probe (9) is disposed for
measuring the said holes when all the movements and operations are
controlled by a pre set program.

2. An apparatus as claimed in claim 1, wherein Y-axis (2) guided by linear
rails is mounted on X-axis beams when servo-motor driven rack and
pinion or ball-screw and box-nut arrangement is disposed for providing
forward and backward movement of Y-axis (2) on X-axis rails (1).
3. An apparatus as claimed in claim 1, wherein X-axis (1), Y-axis (2) and Z-
axes (3, 4) have a rotary encoder or linear scales for accurate position
feedback to the programmable controller.
4. A method of chamfering, de-burring and measurement of large volume
holes for different sizes of heat exchanger and condenser plates, the said
method comprising;
moving Z1-axis (3) carrying a rotating spindle (10) with chamfering
or de-burring tool (11) from a programmed home position to a
programmed position on top of the first hole;
allowing Z1-axis (3) to extend down below the bottom surface of
the condenser plate (6) through programmed motion to chamfer or de-
burr the top surface of the hole by the rotating chamfering or de-burring
tool (11);

allowing Z1-axis (3) to travel up to chamfer or de-burr the bottom
surface of the hole through programmed motion.
repeating the chamfering or de-burring operation for programmed
second and subsequent holes;
allowing the apparatus to move back to a programmed home
position;
allowing Z2-axis (4) having measurement probe 9 to move from a
programmed home position to a programmed position on top of first hole;
making Z2-axis (4) to extend down through a programmed motion
and positioning the set probe at a desired depth in the first hole;
positioning the X-axis (1) and Y-axis (2) of the apparatus at the
first point;
allowing probe 9 to touch side of the hole triggering a signal to the
apparatus' programmable controller and allowing to move to a
programmed second point diametrically opposite to first point and
positioning probe 9 to touch, the wall of the hole triggering a signal to the
apparatus' programmable controller;
allowing the measurement probe 9 to move to a programmed third
point diametrically perpendicular the line from first and second point and

allowing the said probe to touch the wall of the hole triggering a signal to
apparatus programmable controller;
repeating the same for the fourth point;
storing the positional data of all the four points by the apparatus'
programmable controller;
wherein the operation is repeated for second point of the same
hole at a programmed second depth level when the apparatus'
programmable controller stores the positional data of all four points when
the programmable controller calculates based on the measurement data
for eight points of the hole, the diameter of the holes at two desired depth
levels, pitch between the holes, circularity and cylindicity of the holes
wherein the measurement operation is repeated for programmed second
and subsequent holes till all the holes of the condenser plate (6) are
measured when after the measurement operation of last hole, the axes
1,2,3,4 travel back to a programmed home position.

ABSTRACT

An automated apparatus for chamfering/de-burring and measurement of large
volume of holes for different sizes of heat exchanger and condenser, the said
apparatus comprising two horizontal X-axis rail (1), one horizontal Y-axis rail (2)
mounted on X-axis rails (1), two vertical Z-axes (Z1 and Z2 axis) rails (3, 4)
mounted on Y-axis (2) when Z1-axis (3) carrying a rotating spindle (10) having
chamfering/de-burring tool (11) and Z2-axis (4) carrying a measurement probe
(9) wherein the Z1-axis (3) can extend such that the chamfering or de-burring
tool (11) can travel below the bottom surface of the condenser plate (6) for
chamfering or de-burring of the holes, a programmable controller, for motion
control of X, Y and Z axes, a supporting structure having support blocks (8)
disposed in the T-slotted plate (7) and supporting legs (5), wherein the
chamfering tool (11) is disposed for chamfering or de-burring all the holes and
the measurement probe (9) is disposed for measuring the said holes when all the
movements and operations are controlled by a pre set program.