FIELD OF INVENTION
This invention relates to a fixture for facilitating chamfering of pipes.
The length of pipe may vary from 400 mm to 1450 mm with diameters of
219mm to 711mm. The fixture is developed to accommodate all the
lengths for easy and perfect alignment.
BACKGROUND OF THE INVENTION
In power plants piping (Straights and straights with Attachments)
products connect various pressure part components. These pipes are
used in transferring Fuel, saturated steam and water steam mixture.
Shorter pipes are provided to accommodate standard length components
within the piping system without changing their overall layout. The
number of shorter pipes for each boiler varies. Completion of piping
Product Group Manufacturing Assembly using for example SAFOP
machine alone was not accomplished. This was due to its limited
capacity in machining shorter length pipes. Its capacity is limited to
1450mm while pipes of lengths as small as 357mm are designed in
piping system layout. Before making this fixture, all smaller length pipes
are moved to different work centers across unit based on their length.
This process requires movement as well as material coordination.
The fixture of the present invention is robust enough to accommodate
machining of all lengths by varying the type of resting/holding method.
Thus, machining with perfect alignment of pipes over the fixture is
achieved.

The disadvantages associated with the above are as follows:-
The pipe can't be held firmly to the pipe rest while machining.
Frequent errors occur due to operator fatigue.
Job loading is difficult and joint alignment is also not perfect.
OBJECTS OF THE INVENTION
The primary object of the present invention is to provide a fixture for
facilitating chamfering of pipes which overcomes disadvantages
associated with the prior art.
Another object of the present invention is to provide a fixture for
facilitating chamfering of pipes which is simple in construction.
Further object of the present invention is to provide a fixture for
facilitating chamfering of pipes which holds the pipe firmly to the pipe
rest during machining.
Yet another object of the present invention is to provide a fixture for
facilitating chamfering of pipes which is efficient.
Still another object of the present invention is to provide a fixture for
facilitating chamfering of pipes which provides easy job loading and
perfect joint alignment.
Further object of the present invention is to provide a fixture for
facilitating chamfering of pipes which ensures faster changeover to
enhance productivity.

SUMMARY OF THE INVENTION
The fixture for machine holds the pipe in a unique method, aligning the
pipe perfectly to achieve accurate edge preparation. This can be used for
various length pipes which was so far not possible. Said fixture of the
present invention also ensures fool-proofing of the setting which makes
the process of machining error free.
STATEMENT OF INVENTION
According to this invention, there is provided a fixture for facilitating
chamfering of pipes comprising of holding blocks connected with
reinforcements constituting a sub-assembly fabricated with a plurality of
support plates.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Further objects and advantages of this invention will be more apparent
from the ensuing description when read in conjunction with the
accompanying drawings and wherein:
Fig. 1 shows: fixture of the present invention.
Fig. 2 shows: assembly of pipe resting on the fixture.
DETAIL DESCRIPTION OF THE INVENTION WITH REFERENCE TO
THE ACCOMPANYING DRAWINGS:
The present invention discloses a fixture for facilitating chamfering of
pipes. Referring to fig. 1, wherein the holding blocks (1) comprising of
atleast two V blocks. Said blocks are connected with atleast four

reinforcements (3) constituting a sub-assembly (A). A plurality of support
plates (2) are fabricated to the sub-assembly (A) wherein the plates
comprising of atleast two sub units having L-shape.
Further, lifting screws (4) are provided for fastening if required for lifting
and placing.
The holding blocks (1), support plates (2) and reinforcements (3) are
fixedly provided. Said screws are removable and fastened when required.
Referring to fig. 1 showing the fixture for clamping/holding pipe on to the
pipe rest while machining with the following features:
■ Holding Blocks (1) are provided at four ends. These enable pipe to
be placed firmly onto the pipe rest while mounting. They also
ensure vibrations to be arrested while machining.
■ Support Plates (2) are provided at the front end of the fixture for
providing support while processing pipe in the machine. This
support is added to increase the surface contact of the pipe with
fixture as the pipe might fall freely due to its self weight. They also
assist in arresting pipe movement during machining.
■ Reinforcement (3) are provided to hold all individual units of the
fixture together. Their function is to retain the shape of fixture
while machining. This also ensures accurate and consistent
machining to be done for a longer period there by increasing the lift
of the fixture.
■ Lifting screws (4) are provided for mounting and removing fixture
on the V-block stand during changeovers.

Reference may be made to fig. 2 indicating the assembly of pipe resting
on the fixture, in which piston (5) provides vertical force on pipe holding
firmly to the fixture and pipe (6) is to be machined. The fixture (7)
accommodates short length pipes. V-blocks stand (8) is provided so that,
the pipe rests over which the fixture is mounted. Rotating spindle with
Dovetail (9) has cutting tools to carry out machining.
Advantageous features of the Invention
Machining very short lengths in machine.
Chamfering of pipes with outside diameters 609mm, 660 mm&
711mm and of any length.
Used for chamfering bent pipes.
Used for machining all types of materials of pipes.
Productivity enhancement and improved accuracy of the
machining process.
Improved yield of the machine resulting in effectiveness of the
equipment.
It is to be noted that the present invention is susceptible to
modifications, adaptations and changes by those skilled in the art. Such
variant embodiments employing the concepts and features of this
invention are intended to be within the scope of the present invention,
which is further set forth under the following claims:-

WE CLAIM
1. A fixture for facilitating chamfering of pipes comprising of
holding blocks connected with reinforcements constituting a
sub-assembly fabricated with a plurality of support plates.
2. A fixture as claimed in claim 1, wherein said holding blocks
comprising of atleast two V-blocks.
3. A fixture as claimed in claim 1 or 2, wherein the support plates
comprising of atleast two sub units having preferably L-shape.
4. A fixture as claimed in any of the preceding claims, comprising
of lifting screws to fasten upon requirement for lifting and
placing.
5. A fixture as claimed in any of the preceding claims, wherein the
holding blocks, support plates and reinforcements are fixed and
the lifting screws are removable.
6. A fixture for facilitating chamfering of pipes substantially as
herein described with reference to the accompanying drawings.

This invention relates to a fixture for facilitating chamfering of pipes
comprising of holding blocks connected with reinforcements constituting
a sub-assembly fabricated with a plurality of support plates.