FIELD OF THE INVENTION
Present invention generally relates to manufacturing method of economizer
coils used in high pressure steam power plants. More particularly, it relates to
a method of fixture for ladder plate pin setting and welding in the economizer
coils.
BACKGROUND OF THE INVENTION
In High pressure steam generators, Economizer coils are one of the important
products. Economizer coils comprise of upper, middle and lower coils.
Economizer coils having attachments like wide plate, supporting pin welded
with top layer and bottom layer of the economizer circuits. Ladder plates
consist of male plate and female plate. Female plates having holes with
different dimensions of pitch and also having end cutting area for setting and
welding to wide plates. Male plates having supporting pin welded with holes of
female plate. In economizer coil fabrication, male plate is loaded and welded
with wide plates. After the wide plates are welded, bottom layer circuits were
loaded upon the male plates. Then female plate holes are matched with male
plates by supporting pins. In this process, if supporting pins were not matched
with holes, then more pins misalignment will occur. So the supporting pin has
to be adjusted by only hammering. But, the hammering process damages or
brakes supporting pins. So female plates, bottom layer circuits and male plates
are replaced with wide plates. Then, new supporting pin set are made and
welded by male plates. This is time consuming process. Moreover, in the
existing method the pin height of all numbers will not be identical for welding
with female part. Therefore, there is need for an arrangement to overcome
the above drawbacks.
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OBJECT OF THE INVENTION
It is therefore one of the object of the invention to solve aforementioned
problem by developing an arrangement for ladder plate pin.
Yet another object of the invention is introduction of an entirely new and
simplified method for ladder plate welding as well as better quality of welding. Still another object is to reduce the cycle time of economizer coil manufacturing
rework and reduce poor access of welding.
SUMMARY OF THE INVENTION
The present invention is therefore intended to solve one or more of the above
problems through a proposed method for ladder plate pin setting on
Economizer coils.
The ladder pin setting device having supports (Fixed and Adjustable) to
accommodate dimensions such as horizontal, vertical, longitudinal and
misalignment. The fixture method facilitates production in large quantities with
high degree of accuracy, uniform quality and interchangeability at a
competitive cost.
The invention discloses a method for ladder plate pin setting on economizer
coils. The method comprising steps of configuring side supporting mechanism,
configuring height adjustment mechanism, configuring horizontal plate
adjustment for pitch maintenance in said arrangement and configuring vertical
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adjustment for the support pin alignment of the said arrangement. The side
support mechanism is for adjustment of correct hole centre in the ladder
arrangement. The height adjustment mechanism is for setting the support pin
in the arrangement, the horizontal plate adjustment is for maintaining the
arrangement on the ladder plate which is also called as base plate. The vertical
adjustment is achieved through pin vertical alignment angle (PVA), PVA bolt
and PVA nut.
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 the Economizer Coil with attachment welding.
Figure 2 illustrates the male and female plates of ladder plates.
Figure 3 illustrates the ladder plate arrangements details
Figure 4 illustrates Device parts details (as PART-I, PART-2, PART-3, PART-4
and PART – 5)
Figure 5 illustrates ladder pin arrangements with fixtures.
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
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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.
Present invention has been described in five parts with fully adjustment
mechanism.
Referring to fig.1, the economizer coils comprising of wide plate (1), supporting
pin (2), top layer (3) and bottom layer (4). The supporting pin are welded with
the top layer and the bottom layer of the economizer coil.
Referring to fig. 2 which illustrates male plate (5) and female plate (6) of the
economizer coil.
Referring to fig.3, PART-1 illustrates a device stand comprising of a vertical
angle (7), a cross channel (8), a cross angle (9), a horizontal channel (10) and
a horizontal angle (11). This is used for supporting the fixture and all parts are
assembled as per drawing.
Referring to fig.4 (and fig.3), PART-2 illustrates side support mechanism
comprising of a Square box holder (12), a supporting tube (ST) (13), ST Bolt
(13A), a ST Nut (13B), a Parallel support plate(PSP) (14), PSP bolt (14A), PSP
nut (14B), Base plate clamp (BPC) (15), BPC Bolt (15A), BPC Nut (15B).
PART-4 is horizontal plate adjustment comprising of vertical plate (16), vertical
plate bolt (16A) and Vertical Plate Nut (16B).
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PART-5 is vertical adjustment detailed with Pin vertical alignment angle (19),
PVA bolt (19A), PVA nut (19B).
According to fixture, the female plates having holes of different dimensions of
pitch and end cutting area for setting and welding to wide plates. Male plates
having supporting pin welded with holes of female plates. After welding to the
wide plates said bottom layer (4) is loaded upon the male plates (5). Further
procedure for alignment of the fixture can be described in following steps:
Step-1 is setting pitch plate (6) on the fixture for hole alignment.
Step-2 is adjusting a support pin (2) height according to the dimensions.
Step-3 is loading ladder plate (5) on top of height adjustment support plate.
Step-4 is feeding support pin to ladder holes.
Step-5 is aligning the ladder plate and support pins horizontally and vertically
with the help of adjustable mechanism on fixture.
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WE CLAIM:
1. A method for ladder plate pin setting on Economizer coils, the method
comprising steps of:
- configuring a side support mechanism for said ladder plate pin setting
arrangement;
- configuring a height adjustment mechanism for setting a support pin (2) to
said arrangement;
- configuring a horizontal plate adjustment for pitch maintenance of said
arrangement;
- configuring a vertical adjustment for said support pin alignment to the said
arrangement.
2. The method as claimed in claim 1, wherein the side support mechanism is
for adjusting and maintaining correct hole center in said arrangement.
3. The method as claimed in claim 1, wherein height adjustment mechanism is
achieved by setting a support pin (2) with a male part (5).
4. The method as claimed in claim 1, wherein achieving horizontal plate
adjustment for maintaining the arrangement on the ladder plate which is
also a base plate.
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5. The method as claimed in claim 1, wherein vertical adjustment for said
support pin alignment is achieved with pin vertical alignment angle (19), PVA
bolt (19A) and PVA nut (19B).