Title of Invention

AN IMPROVED DEVICE FOR ISOLATION OF PULVERIZED FUEL LINES SUPPLYING PULVERIZED FUEL TO THE BURNERS DURING BOILER OPERATION

Abstract The invention relates to an improved device for isolation of pulverized fuel lines supplying pulverized fuel to the burners during boiler operation in thermal power plants, the device comprising a gate body (1,2) having an extended gate guide (3) at the bottom through which a sliding plate (8) moves upward and downward to open and close a fuel line; the sliding plate (8) attached to a super structure (10) and impregnable by the gate body (1,2) and enabled to slide through an in built packing chamber (17) and to rest on atleast one spherical ball (15) in a closed condition to prevent leakage of fuel; the sliding plate (8) operable by means of a plurality of actuators (4) through a solenoid valve (11) and controlled by limit switches (17); the packing chamber (17) having a plurality of packing retainer plate (14) fastened with a several adjustable bolts to make the chamber (17) leak proof.
Full Text FIELD OF THE INVENTION
The present invention generally relates to an isolator device adaptable to
pulverized fuel line in a boiler. More particularly, the present invention
relates to an improved device for isolation of pulverized fuel lines
supplying pulverized fuel to the burners during boiler operation in thermal
power plants.
BACKGROUND OF THE INVENTION
In a typical thermal power plant, boilers are generally operated by
pulverized fuel as a source of input energy. Pulverized fuel from the
pulverizers are fed to the burners by air through a plurality of parallel
pipes. The air carrying the fuel to the burner tip is called primary air
which atomises these fuel to the hearth of the boiler. A secondary air is
supplied to the boiler through a compartmentalized secondary air duct for
combustion of the fuel. This secondary air is distributed and regulated by
a secondary air damper actuated by air cylinders. A plurality of fuel
compartments are sandwiched in between one over the other air
compartment. The burner tips are tilted upward and downward by means
of tilt drives and tilt links. Hence the pulverized fuel firing system, in
particular constitutes a corner firing system, and comprises damper drives,
tilt drives and monitoring systems in addition to the burner components.
Hence they need attention and continuous monitoring while the boiler is in
operation.

Conventional devices of pulverized fuel line isolation, almost entirely forfeit
the maintenance area of the burners and makes it difficult for monitoring
the burner area. Furthermore, they interfere with the damper drive
mechanism and other accompanying link components, which are
otherwise essential for the efficient boiler operation. The conventional
valves require frequent relocations and modifications during the assembly
for the maintenance work. Also, the overhung components of the
actuators of the conventional valves generate overstress to the adjoining
components thereby affecting the life of the isolation device.
US patent No.5,292,105 discloses an improved knifegate valve, where the
improvement comprises, joining the securing device for securing gland
box to the support. The support may comprise a bridge supported in
spaced relation to the body by pillars connected to the body.
In this art, the packing is secured by tightening the retainer by means of
fasteners.
US patent No. 5,890,700 entitled "under gate valve" by Clarkson, et al
discloses a packingless gate valve which includes a housing having
opposed similar housing halves with primary resilient sleeve units which
compressibly engage each other in the valve-open condition and engage
opposite sides of the gate in the valve-closed condition.


This art incorporates gland packing for the sealing and compressing the
gland packing by tightening the nuts which in the turn arrest the leakage.
OBJECTS OF THE INVENTION
It is therefore, an object of the present invention to propose an improved
device for isolation of pulverized fuel lines for isolation of fuel with plurality
actuators supplying pulverized fuel to the burners during boiler operation
in a thermal power plants, which eliminates the disadvantages of prior art.
Another object of the present invention is to propose an improved device
for isolation of pulverized fuel lines for isolation of fuel with plurality
actuators supplying pulverized fuel to the burners during boiler operation
in a thermal power plants which requires less space near the corner area.
A still another object of the present invention is to propose an improved
device for isolation of pulverized fuel lines for isolation of fuel with plurality
actuators supplying pulverized fuel to the burners during boiler operation
in a thermal power plants which is smaller in size.
A further object of the present invention is to propose an improved device
for isolation of pulverized fuel lines for isolation of fuel with plurality


actuators supplying pulverized fuel to the burners during boiler operation
in a thermal power plants which provides liners in the super structure to
ensure a smooth movement and prevents any distortion due to
slenderness of the isolation plate.
A still further object of the present invention is to propose an improved
device for isolation of pulverized fuel lines for isolation of fuel with plurality
actuators supplying pulverized fuel to the burners during boiler operation
in a thermal power plants which is enabled to operate both the cylinders
simultaneously by a single solenoid valve to ensure smooth operation.
Yet further object of the present invention is to propose an improved
device for isolation of pulverized fuel lines for isolation of fuel with plurality
actuators supplying pulverized fuel to the burners during boiler operation
in a thermal power plants which enables the isolation plate to seat on the
balls held in position by the gate guide at the end of travel.
SUMMARY OF THE INVENTION
The isolation device of present invention has a plurality of actuators
mounted on extension of gate guides. Since the load is shared by two
actuators, the size of the actuators is also reduced to nearly half of its
original size.


At the end of the travel, the isolation plate seats on the round parts locked
in position by the gate guide, which prevents jamming.
The isolation plate travels in the spaced super structure having liner plates
with guide and prevents distortion due to slenderness of the isolation
plate.
The actuators are connected to both sides of the isolation plate by means
of connectors and securing parts. The operation of actuators are
controlled by a single solenoid valve, which ensures opening of, closing
and smooth operation the device. The limit switches mounted on the
super structure are actuated by the plate at the end of its travel on both
sides. The packing is retained by the retainer plates attached on both
sides of the gate body.
The solenoid valve is located at an advantageous location, which facilitates
easy maintenance in contrast to the conventional valves.
Accordingly, there is provided an improved device for isolation of
pulverized fuel lines supplying pulverized fuel to the burners during boiler
operation in thermal power plants, the device comprising a gate body
having an extended gate guide at the bottom through which a sliding
plate moves upward and downward to open and close fuel line; the sliding

plate is attached to a super structure and impregnable by the gate body
and enabled to slide through an in built packing chamber and to rest on
atleast one spherical ball in a closed condition to prevent leakage of fuel;
the sliding plate operable by means of a plurality of actuators through a
solenoid valve and controlled by limit switches ; the packing chamber
having a plurality of packing retainer plate fastened with a several
adjustable bolts to make the chamber leak proof.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Fig-1- shows an elevational view of the device according to the invention.

Fig-2- shows a side view of the device of Fig. 1.
Fig-3- shows location of the balls in the gate guide of the device of Fig. 1.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE
INVENTION
As shown in figs-1 & 2, the isolation device (13) is provided with an
extended gate guide (3), to which the gate body (1,2) are mounted on
both sides. The extension of the gate guide (3) on both sides act as
support for the mounting of an actuator (4). The actuators (4) are
connected to an isolation plate (8) by means of connectors and securing
parts (6). The isolation plate (8) moves thorough a gland packing (5)
upward and downward for opening and closing. The tightness of packing
is controlled by a plurality of packing retainer (5) and by adjusting a
plurality of bolts and nuts (16) thereof. A packing chamber (17) is formed
by a number of packing retainer plates (14), which are attached to the
gate body plates (1,2).
A gate insert (12) is inserted in the gate body for enhancing the life. At
the end of travel, the isolation plate (8) seats on several balls (15) held in
position by the gate guide (3), which prevents jamming. The isolation
plate (8) is lifted or dragged through the gland packing (5) by the
actuators (4).

A plurality of limit switches (7) are mounted on the super structure, which
are actuated by the isolation plate (8) at the end of its travel. A plurality of
liners (9) are fastened to the super structure (10) to ensure smooth
movement of the isolation plate (8) and to prevent deflection of plate
during the operation.
The actuators (4) are actuated by a single solenoid valve (11) mounted on
the top of the gate body (1,2).




WE CLAIM
1. An improved device for isolation of pulverized fuel lines supplying
pulverized fuel to the burners during boiler operation in thermal
power plants, the device comprising:
- a gate body (1, 2) having an extended gate guide (3) at the
bottom through which a sliding plate (8) moves upward and
downward to open and close a fuel line;
- the sliding plate (8) attached to a super structure (10) and
impregnable by the gate body (1,2) and enabled to slide
through an in built packing chamber (17) and to rest on
atleast one spherical ball (15) in a closed condition to
prevent leakage of fuel;
- the sliding plate (8) operable by means of a plurality of
actuators (4) through a solenoid valve (11) and controlled by
limit switches (17);
- the packing chamber (17) having a plurality of packing
retainer plate (14) fastened with a several adjustable bolts to
make the chamber (17) leak proof.

2. The device (13) as claimed in claim 1, wherein the plurality of the
actuators (4) are fitted on both sides of the gate guides (3).
3. The device (13) as claimed in claim 3, wherein the sliding plate (8)
is enabled to pass through a super structure (10) by means of the
gate guides (3).
4. The device (13) as claimed in the claim 1, wherein the actuators (4)
are connected to the sliding plate (8) by a plurality of connectors
including securing parts (6).
5. The device (13) as claimed in the claim 1, comprising a plurality of
packing retainers (5) firmly fixed to the sides of the gate body
(1,2) with adjustable nuts and bolts (16).
6. The device (13) as claimed, in claim 1, wherein the packing
retainers (5) are firmly fixed in a center part of the gate body (1,2)
7. An improved device for isolation of pulverized fuel lines supplying
pulverized fuel to the burners during boiler operation in thermal
power plants as substantially described and illustrated herein with
reference to the accompanying drawings.


The invention relates to an improved device for isolation of pulverized fuel
lines supplying pulverized fuel to the burners during boiler operation in
thermal power plants, the device comprising a gate body (1,2) having an
extended gate guide (3) at the bottom through which a sliding plate (8)
moves upward and downward to open and close a fuel line; the sliding
plate (8) attached to a super structure (10) and impregnable by the gate
body (1,2) and enabled to slide through an in built packing chamber (17)
and to rest on atleast one spherical ball (15) in a closed condition to
prevent leakage of fuel; the sliding plate (8) operable by means of a
plurality of actuators (4) through a solenoid valve (11) and controlled by
limit switches (17); the packing chamber (17) having a plurality of
packing retainer plate (14) fastened with a several adjustable bolts to
make the chamber (17) leak proof.

Documents:

01131-kol-2006 abstract.pdf

01131-kol-2006 claims.pdf

01131-kol-2006 correspondence others.pdf

01131-kol-2006 description(complete).pdf

01131-kol-2006 drawings.pdf

01131-kol-2006 form-1.pdf

01131-kol-2006 form-2.pdf

01131-kol-2006 form-3.pdf

01131-kol-2006 general power of attorney.pdf

1131-KOL-2006-ABSTRACT.pdf

1131-KOL-2006-CLAIMS.pdf

1131-KOL-2006-CORRESPONDENCE.pdf

1131-kol-2006-correspondence1.1.pdf

1131-KOL-2006-DESCRIPTION (COMPLETE).pdf

1131-KOL-2006-DRAWINGS.pdf

1131-KOL-2006-EXAMINATION REPORT REPLY RECIEVED.pdf

1131-kol-2006-examination report.pdf

1131-KOL-2006-FORM 1-1.1.pdf

1131-KOL-2006-FORM 1.pdf

1131-kol-2006-form 18.pdf

1131-KOL-2006-FORM 2-1.1.pdf

1131-KOL-2006-FORM 2.pdf

1131-kol-2006-form 3.pdf

1131-KOL-2006-FORM-27.pdf

1131-kol-2006-gpa.pdf

1131-kol-2006-granted-abstract.pdf

1131-kol-2006-granted-claims.pdf

1131-kol-2006-granted-description (complete).pdf

1131-kol-2006-granted-drawings.pdf

1131-kol-2006-granted-form 1.pdf

1131-kol-2006-granted-form 2.pdf

1131-KOL-2006-GRANTED-LETTER PATENT.pdf

1131-kol-2006-granted-specification.pdf

1131-KOL-2006-OTHERS 1.1.pdf

1131-KOL-2006-OTHERS.pdf

1131-kol-2006-reply to examination report.pdf

abstract-01131-kol-2006.jpg


Patent Number 249856
Indian Patent Application Number 1131/KOL/2006
PG Journal Number 46/2011
Publication Date 18-Nov-2011
Grant Date 16-Nov-2011
Date of Filing 26-Oct-2006
Name of Patentee BHARAT HEAVY ELECTRICALS LIMITED
Applicant Address REGIONAL OPERATIONS DIVISION (ROD), PLOT NO: 9/1, DJBLOCK 3RD FLOOR, KARUNAMOYEE, SALT LAKE CITY, KOLKATA-700091, HAVING ITS REGISTERED OFFICE AT BHEL HOUSE, SIRI FORT, NEW DELHI-110049, INDIA
Inventors:
# Inventor's Name Inventor's Address
1 MURUGAIYAN THANDAPANI PRODUCT ENGG./FB, BHEL, TRICHY-14
2 RAMASAMY SESHARAJAN PRODUCT ENGG./FB, BHEL, TRICHY-14
3 KRISHNAN ANBU PRODUCT ENGG./FB, BHEL, TRICHY-14
PCT International Classification Number F23D 1/00,F16K 3/316
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 NA