U.S. patent application number 13/302008 was filed with the patent office on 2013-05-23 for method of manufacturing door frame for wind tower.
This patent application is currently assigned to PSM, INC.. The applicant listed for this patent is Jong-hun Kang, Yong-chul Kwon, Dong-soo SHIN, Myung-jun Song. Invention is credited to Jong-hun Kang, Yong-chul Kwon, Dong-soo SHIN, Myung-jun Song.
Application Number | 20130125605 13/302008 |
Document ID | / |
Family ID | 48425492 |
Filed Date | 2013-05-23 |
United States Patent
Application |
20130125605 |
Kind Code |
A1 |
SHIN; Dong-soo ; et
al. |
May 23, 2013 |
METHOD OF MANUFACTURING DOOR FRAME FOR WIND TOWER
Abstract
Disclosed herein is a method of manufacturing a door frame for a
wind tower. The method includes a first step of forging a circular
planar substance, thereby forming a through hole in a central
portion of the substance, a second step of heating the substance
that was processed in the first step, a third step of ring-rolling
the heated substance around the through hole in an annular shape
such that a circumstance of a center hole of the substance is equal
to a length of a center line of the door frame, a fourth step of
upset-forging the annular substance so that opposite sides of the
substance are pressed to form linear sections, and a fifth step of
fine-finishing the substance that was processed by the fourth step,
thus completing the door frame.
Inventors: |
SHIN; Dong-soo; (Busan,
KR) ; Kwon; Yong-chul; (Changwon-si, KR) ;
Kang; Jong-hun; (Busan, KR) ; Song; Myung-jun;
(Busan, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SHIN; Dong-soo
Kwon; Yong-chul
Kang; Jong-hun
Song; Myung-jun |
Busan
Changwon-si
Busan
Busan |
|
KR
KR
KR
KR |
|
|
Assignee: |
PSM, INC.
Gangseo-Gu
KR
|
Family ID: |
48425492 |
Appl. No.: |
13/302008 |
Filed: |
November 22, 2011 |
Current U.S.
Class: |
72/356 |
Current CPC
Class: |
F05B 2240/00 20130101;
E04H 12/003 20130101; B21K 1/761 20130101; B21K 21/00 20130101 |
Class at
Publication: |
72/356 |
International
Class: |
B21K 21/00 20060101
B21K021/00 |
Claims
1. A method of manufacturing a door frame for a wind tower,
comprising: forging a circular planar substance, thereby forming a
through hole in a central portion of the substance; heating the
substance processed by the forging; ring-rolling the heated
substance around the through hole in an annular shape such that a
circumstance of a center hole of the substance is equal to a length
of a center line of the door frame; upset-forging the annular
substance so that opposite sides of the substance are pressed to
form linear sections; and fine-finishing the substance processed by
the upset-forging, thus completing the door frame.
2. The method as set forth in claim 1, wherein a ratio (t/w) of a
thickness (t) to a width (w) of the substance processed by the
fine-finishing ranges from 0.5 to 1.
3. The method as set forth in claim 1, wherein in the
fine-finishing the substance, a length ratio (a/b) of the linear
section (a) formed in each of the opposite sides of the substance
to a curved section (b) is 0.7 or more.
4. The method as set forth in claim 1, wherein a ratio (w/L) of a
width (w) to a height (L) of the substance processed by the
fine-finishing is 0.1 or more.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to methods of
manufacturing door frames for wind towers and, more particularly,
to a method of manufacturing a door frame installed in a wind
tower.
BACKGROUND OF THE INVENTION
[0002] Limited oil resources will become exhausted someday. Thus, a
lot of research has recently been done into alternative energies
which can substitute for the resources and many different kinds of
technologies aiming to develop alternative energy have been
proposed. Particularly, many technologies for generating
electricity from natural energy sources have been studied because
the conclusion was reached that natural energy sources, such as the
sun, wind, water, etc., are almost infinite and can be used as
ideal alternative energy sources. A wind power generation
technology in which blades are rotated by wind power so that
electricity is generated is at the stage of practical
application.
[0003] However, in wind power generation, a vast land area and
large expenses are required to install single wind power generating
equipment and system.
[0004] Various ways to reduce the production cost of wind power
generating equipment have recently been proposed.
[0005] FIG. 1 is a perspective view showing a typical wind
tower.
[0006] Typically, a propeller 5 is provided on the upper end of a
wind tower 1 and connected to a generation part 4. To allow a
worker to inspect the generation part 4, a door 2 with a door frame
is installed at a predetermined position in the wind tower 1.
[0007] As shown in FIG. 2, forming the door frame 20 includes
forging a raw substance 10 (a slab or ingot) in a planar shape,
rough-machining the substance 10, and fine-finishing it thereby
producing a final product.
[0008] However, in the conventional manufacturing method, a large
amount of cut-out portions 12 are removed from the raw substance
during rough-machining and fine-finishing, thus increasing waste of
material and the time it takes to manufacture it.
SUMMARY OF THE INVENTION
[0009] Accordingly, the present invention has been made keeping in
mind the above problems occurring in the prior art, and an object
of the present invention is to provide a method of manufacturing a
door frame for a wind tower which can reduce the cost and time
required to manufacture the door frame.
[0010] In order to accomplish the above object, the present
invention provides a method of manufacturing a door frame for a
wind tower, including a first step of forging a circular planar
substance, thereby forming a through hole in a central portion of
the substance, a second step of heating the substance that was
processed in the first step, a third step of ring-rolling the
heated substance around the through hole in an annular shape such
that a circumstance of a center hole of the substance is equal to a
length of a center line of the door frame, a fourth step of
upset-forging the annular substance so that opposite sides of the
substance are pressed to form linear sections, and a fifth step of
fine-finishing the substance that was processed by the fourth step,
thus completing the door frame.
[0011] Preferably, a ratio (t/w) of a thickness (t) to a width (w)
of the substance processed by the fine-finishing may range from 0.5
to 1.
[0012] In the fifth step, a length ratio (a/b) of the linear
section (a) formed in each of the opposite sides of the substance
to a curved section (b) may be 0.7 or more.
[0013] Further, a ratio (w/L) of a width (w) to a height (L) of the
substance processed by the fine-finishing may be 0.1 or more.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The above and other objects, features and advantages of the
present invention will be more clearly understood from the
following detailed description taken in conjunction with the
accompanying drawings, in which:
[0015] FIG. 1 is a perspective view showing a typical wind
tower;
[0016] FIG. 2 is a view illustrating an example of a conventional
method of manufacturing a door frame for a wind tower;
[0017] FIGS. 3A through 3E are views illustrating a method of
manufacturing a door frame for a wind tower, according to an
embodiment of the present invention;
[0018] FIGS. 4A and 4B are views comparing a final product to an
intermediate product which has been processed at a third step of
the door frame manufacturing method according to the embodiment of
the present invention;
[0019] FIG. 5 is a plan view of a door frame for a wind tower which
is manufactured by the door frame manufacturing method according to
the present invention; and
[0020] FIG. 6 is a perspective view of FIG. 5.
DETAILED DESCRIPTION OF THE INVENTION
[0021] Hereinafter, a preferred embodiment of the present invention
will be described in detail with reference to the attached
drawings.
[0022] FIGS. 3A through 3E are views illustrating a method of
manufacturing a door frame for a wind tower, according to the
embodiment of the present invention.
[0023] As shown in FIGS. 3A through 3E, the door frame
manufacturing method according to the present invention includes
five steps. As shown in FIG. 3A, in a first step, a through hole is
formed through a central portion of a circular planar substance by
a forging process. In a second step, the substance that has been
processed in the first step is heated. As shown in FIG. 3B, the
substance that has been heated at the second step is shaped into an
annular shape around the through hole by a ring rolling method, in
a third step. As shown in FIGS. 3C and 3D, in a fourth step,
opposite sides of the annular substance are pressed by upset
forging to form linear sections therein. As shown in FIG. 3E, in a
fifth step, the substance that has been processed in the fourth
step is fine-finished, thus producing a door frame.
[0024] In detail, first, before the first step, the substance is
heated to a predetermined temperature by a furnace and machined in
a circular planar shape by a rough-shaping process which is a
pre-forging process.
[0025] The substance that has passed through the preliminary step
is processed by the first step so that the through hole 110 is
formed through the central portion of the substance by
punching.
[0026] Subsequently, the second step is performed, which is
carrying out a heating process required to conduct the ring rolling
process of the third step. In the third step, the diameter of the
annular substance is extended.
[0027] The ring rolling method refers to a method in which an
annular substance is pressed by a forging machine, including a main
roll, a rolling mandrel and an axle roll which is provided at each
of upper and lower sides, so that the diameter of the substance is
extended into a desired shape.
[0028] Here, the circumference of the center hole of the substance
that has been processed by the ring rolling method in the third
step corresponds to the length of a center line of the door frame
which is a final product.
[0029] FIGS. 4A and 4B are views comparing the final product to the
substance that has been processed in the third step of the door
frame manufacturing method according to the embodiment of the
present invention.
[0030] The present invention must be designed such that the
circumstance of the center hole 14 of the substance 10 of FIG. 4A
that has been processed in the third step is the same as the length
of the center line 24 of the door frame 20 of FIG. 4B which is the
final product.
[0031] Subsequently, as shown in FIGS. 3C and 3D, in the fourth
step, the opposite sides of the annular substance are pressed by
upset forging so that the linear sections are formed in the
substance. As shown in FIG. 3E, the fifth step includes
fine-finishing the substance that has been processed in the fourth
step, thus completing the door frame.
[0032] Meanwhile, in the fourth step, the substance 100 must be
re-heated to a predetermined temperature when upset forging it. The
heated substance 100 is placed on a lower mold 50, and an upper
mold 60 is pressed by a press so that a linear section is formed in
each of the opposite sides of the substance 100. In the fifth step,
the substance is fine-finished, thus completing the final
product.
[0033] Several conditions must be met in order for upset forging to
be used to make the linear sections.
[0034] A ratio (t/w) of a thickness t to a width w of the
substance, which has been processed in the fifth step which is the
final step, must range from 0.5 to 1. A length ratio (a/b) of a
linear section a, which is formed in each of the opposite sides of
the substance, to a curved section b must be 0.7 or more. A ratio
(w/L) of the width w to a height L of the substance must be 0.1 or
more.
[0035] FIG. 5 is a plan view of the door frame manufactured by the
door frame manufacturing method according to the present invention.
FIG. 6 is a perspective view of FIG. 5.
[0036] As shown in FIG. 5, each of the linear sections a which are
formed on the opposite sides of the substance must be shorter than
the curved section b (in detail, having an elliptical shape) which
is formed in each of both ends of the substance, and the ratio
(a/b) must be 0.7 or more. If the linear section is excessively
long, the substance may be deformed during the forging process.
[0037] Furthermore, if the width w of the substance is excessively
small with respect to the height L of the substance, or if the
thickness t of the substance is excessively small or large with
respect to the width w of the substance, the substance may also be
deformed during the upset forging process. Therefore, the ratio
(t/w) of the thickness t to the width w of the substance must range
from 0.5 to 1, and the ratio (w/L) of the width w to the height L
of the substance must be 0.1 or more.
[0038] As described above, a method of manufacturing a door frame
for a wind tower according to the present invention includes
shaping a substance in a shape similar to that of the door frame
through ring-rolling and upset-forging processes, and
fine-finishing it, thus completing a final product. Therefore,
unlike the conventional art, a rough machining process can be
omitted. Thereby, the cost and time required to manufacture the
door frame can be markedly reduced.
[0039] The critical technical spirit of the present invention is to
provide a method of a door frame for a wind tower. Although the
preferred embodiment of the present invention has been disclosed
for illustrative purposes, those skilled in the art will appreciate
that various modifications, additions and substitutions are
possible, without departing from the scope and spirit of the
invention as disclosed in the accompanying claims.
* * * * *