KR20150008226A - In-situ crankshaft reconditioning method - Google Patents

In-situ crankshaft reconditioning method Download PDF

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Publication number
KR20150008226A
KR20150008226A KR20130081341A KR20130081341A KR20150008226A KR 20150008226 A KR20150008226 A KR 20150008226A KR 20130081341 A KR20130081341 A KR 20130081341A KR 20130081341 A KR20130081341 A KR 20130081341A KR 20150008226 A KR20150008226 A KR 20150008226A
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KR
South Korea
Prior art keywords
crankshaft
heat treatment
polishing
cutting
machining
Prior art date
Application number
KR20130081341A
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Korean (ko)
Inventor
황종석
김중삼
송기주
Original Assignee
주식회사 디.에스.케이
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Application filed by 주식회사 디.에스.케이 filed Critical 주식회사 디.에스.케이
Priority to KR20130081341A priority Critical patent/KR20150008226A/en
Publication of KR20150008226A publication Critical patent/KR20150008226A/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
    • B23P23/00—Machines or arrangements of machines for performing specified combinations of different metal-working operations not covered by a single other subclass
    • B23P23/04—Machines or arrangements of machines for performing specified combinations of different metal-working operations not covered by a single other subclass for both machining and other metal-working operations
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B9/00—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor
    • B24B9/02—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground
    • B24B9/04—Machines or devices designed for grinding edges or bevels on work or for removing burrs; Accessories therefor characterised by a special design with respect to properties of materials specific to articles to be ground of metal, e.g. skate blades
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/06—Surface hardening
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/26—Methods of annealing
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C3/00—Shafts; Axles; Cranks; Eccentrics
    • F16C3/04—Crankshafts, eccentric-shafts; Cranks, eccentrics

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Materials Engineering (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Thermal Sciences (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • General Engineering & Computer Science (AREA)
  • Ocean & Marine Engineering (AREA)
  • Optics & Photonics (AREA)
  • Grinding Of Cylindrical And Plane Surfaces (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)

Abstract

The present invention relates to an in-situ processing method of a crankshaft which is a standardized processing method capable of conveniently, precisely, and accurately process the crankshaft in a medium- or a large-sized ship without separating the crankshaft; thereby improving the efficiency and quality in processing the crankshaft. According to the present invention, an in-situ processing method of a crankshaft comprises: a processing apparatus preparation step of preparing a crankshaft processing apparatus to process the crankshaft; a primary heat treatment step of primarily performing a heat treatment in order to lower the hardness of the target portion of the crankshaft; a target diameter calculation step of calculating the target diameter of the crankshaft; an equipment mounting step of mounting a crankshaft processing apparatus on the crankshaft; a cutting process step of performing a cutting process on the target portion to the target diameter of the crankshaft by installing a cutting function part on the crankshaft processing apparatus; a grinding process step of performing a grinding process on the target portion of the crankshaft by installing a grinding function part on the crankshaft processing apparatus after the cutting process is performed on the target portion of the crankshaft; a polishing process step of performing a polishing process on the target portion of the crankshaft by installing a polishing function part on the crankshaft processing apparatus after the grinding process is performed on the target portion of the crankshaft; a primary inspection step of measuring the surface roughness, the straightness, and the roundness of the crankshaft on which the polishing process is completed; a secondary heat treatment step of performing a heat treatment to recover the hardness of the target portion of the crankshaft; and a secondary inspection step of measuring the surface roughness and the hardness of the crankshaft after the secondary heat treatment is performed on the crankshaft.

Description

[0001] In-situ crankshaft reconditioning method [0002]

The present invention relates to an in-process method for crankshaft, and more particularly, to a crankshaft in-situ machining method capable of re-machining without removing the crankshaft in the field.

Generally, a crankshaft is a main component of an engine that is supported by a bearing in a crank chamber of an engine and connected to a lower end of a vertically reciprocating piston by a connecting rod to convert a reciprocating motion of the piston into rotational motion.

The crankshaft includes a crank pin to which the end of the connecting rod opposite the piston is engaged, a crank web located on both sides of the crank pin for adjusting the rotational inertia of the crank shaft, As a center of rotation of the crankshaft.

The crankshaft has a fillet portion, which is a rounded portion, to prevent a crack due to fatigue stress at a portion where the crank pin and the crank web are connected.

Among the constituent elements of the crankshaft structured as described above, the crank pin is a portion where combustion energy generated in the cylinder during the explosion stroke of the engine is directly transmitted through the piston and the connecting rod, and is a primary The surface of the crank pin is frequently damaged by abrasion or scratches due to a secondary factor such as a factor and a resulting oil film loss.

In order to solve this problem, the crank pin needs to be regularly reworked or the like, and conventionally, the crankshaft is removed from the engine, and a crankshaft such as a crankshaft such as the Korean Patent Registration No. 10-0942017 However, such a conventional technique has a problem that the accuracy of machining is low, the machining apparatus is complicated, particularly, it is difficult to remove the crankshaft, and it is difficult to obtain a uniform machining quality.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a method of forming a crankshaft, which can relatively easily and precisely crankshaft the crankshaft without removing the crankshaft, And to provide an in-process crankshaft method capable of improving the efficiency of the crankshaft and obtaining excellent machining quality.

As a means for solving the above problems, the present invention provides an in-situ machining method for a crankshaft,

A step of preparing a machining apparatus for preparing a crankshaft machining apparatus for crankshaft machining,

A primary heat treatment step of performing a primary heat treatment in order to lower the hardness of the crankshaft processing target part,

A working target diameter calculating step of calculating a target diameter of the crankshaft,

An apparatus mounting step of mounting the crankshaft working apparatus to the crankshaft,

A cutting process step of providing a cutting function part to the crankshaft working device to cut the crankshaft to a target diameter of the crankshaft,

A polishing processing step of providing a polishing function part to the crankshaft working device to polish a machining target part of the crankshaft subjected to the cutting process,

A polishing processing step of polishing the crankshaft to be machined by installing a polishing function part in the crankshaft machining device,

A primary inspection step of measuring the surface roughness, straightness, and roundness of the crankshaft completed polishing,

A secondary heat treatment performing step of performing a heat treatment for restoring the hardness of the part to be processed of the crankshaft and

And a secondary detection step of measuring the surface roughness and hardness of the crankshaft subjected to the secondary heat treatment.

The heat treatment in the primary heat treatment step and the secondary heat treatment step is performed by covering a heat treatment mat on a part to be processed, and the temperature of the heat treatment mat is controlled by a temperature control device.

The crankshaft machining apparatus includes:

A pair of rotating rings formed on the outer circumference to be engaged with the chain,

A connecting bar in which the pair of rotating rings are coupled so as to maintain a constant spacing from each other; and

A chain wound around the rotary ring, and a motor coupled to the chain and having a sprocket for rotationally driving the chain.

In addition,

A pair of through holes through which the connecting bar passes for fixing to a connecting bar of the crankshaft working apparatus,

A screw hole having a female screw threadably engaged with a male screw portion of the feed bar for feeding the cutting function portion,

A cutting tool for cutting the crankshaft,

A tool holder for fixing the cutting tool, and a tool feed tool for adjusting the machining depth by moving the tool holder back and forth.

In addition,

An abrasive portion bracket having a coupling means such as a bolt coupled to the rotary ring at one side thereof,

An abrasive tool supported on the abrasive portion bracket by a bearing and installed to be rotatable about a rotation axis,

A driven bevel gear coupled to a rotating shaft of the polishing tool,

A driven bevel gear which is gear-engaged with the driven bevel gear,

And the drive side bevel gear is coupled to the drive shaft.

Through the above-mentioned problem solving means, the crankshaft in-process method of the present invention can relatively easily and precisely crankshaft machining without removing the crankshaft, thereby improving the efficiency of crankshaft machining, There is an advantage to be obtained.

In addition, due to the above-described advantages, there is an advantage that the maintenance time can be shortened and the ship's operational rotation can be increased and the economic loss can be minimized.

FIG. 1 is a flowchart briefly showing a method of processing an in-situ crankshaft according to the present invention.
2 and 3 are perspective views showing a crankshaft working apparatus used in an in-situ crankshaft working method according to the present invention.
4 is a sectional view showing a cutting function part used in a crushshaft in-between processing method according to the present invention.
5 is a cross-sectional view showing a polishing function part used in an in-situ machining method of a crankshaft according to the present invention.
6 is a cross-sectional view showing a polishing function part used in an in-situ machining method of a crankshaft according to the present invention.

A preferred embodiment of a crankshaft in-between processing method according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a flowchart schematically showing a crankshaft in-process method according to the present invention, FIGS. 2 and 3 are perspective views showing a crankshaft working apparatus used in an in-process crankshaft method according to the present invention, 4 is a sectional view showing a cutting function part used in an in-situ machining method of a crankshaft according to the present invention, FIG. 5 is a sectional view showing a grinding function part used in an in-situ machining method of a crankshaft according to the present invention, Sectional view showing a polishing function part used in an in-situ machining method of a crankshaft according to the present invention.

As shown in FIG. 1, the crankshaft in-situ machining method according to the present invention is a machining method for repairing a crankshaft CS on the spot without removing the crankshaft CS. The machining apparatus includes a machining apparatus preparation step, a primary heat treatment execution step, The diameter calculation step, the equipment mounting step, the cutting step, the polishing step, the polishing step, the primary inspection step, the secondary heat treatment execution step, and the secondary inspection step.

The crankshaft in-between processing method according to the present invention as described above will be described in detail for each step.

First, the machining apparatus preparation step is a step of preparing a crankshaft machining apparatus 1 for crankshaft (CS) machining. The crankshaft machining apparatus 1 includes a chain (not shown) A connecting bar 3 to which a pair of rotary rings 2 having teeth formed to engage with the rotary ring 2 and the pair of rotary rings 2 are coupled so as to maintain a constant spacing from each other, And a motor 6 connected to the chain 4 and provided with a sprocket 5 for rotationally driving the chain 4.

The rotary ring 2 is provided with a coupling means for coupling various tools to be described later, and the coupling means includes a bolt coupling hole, a bracket, and the like.

The primary heat treatment step is a step of primarily performing a heat treatment to lower the hardness of the crankshaft (CS) to be machined. The heat treatment mat is placed on a part to be machined such as a crank pin (CP) So that desired hardness can be obtained at the portion to be processed.

Through this process, subsequent machining such as cutting and polishing can be performed quickly and easily.

The machining target diameter calculating step is a step of calculating the target diameter of the crankshaft CS, in particular, the crank pin CP, by measuring the surface roughness, the crack depth and the like, thereby grasping the state of the crankshaft CS, The depth is calculated.

When the machining target diameter is calculated, the crankshaft machining apparatus 1 is subjected to an equipment mounting step of mounting the crankshaft machining apparatus 1 on the crankshaft CS. In order to facilitate the mounting, the rotating ring 2 of the crankshaft working apparatus 1 is preferably manufactured so as to be divided into two parts having the same size and separated from each other as shown in Fig.

In the cutting step, the cutting function unit 10 is installed in the crankshaft working apparatus 1 so that the diameter of the crankshaft CS, particularly the crankpin CP, is machined so as to have a machining target diameter.

4, the cutting function unit 10 includes a pair of through holes (not shown) through which the connecting bar 3 passes to be fixed to the connecting bar 3 of the crankshaft working apparatus 1 A screw hole 12 formed with a female screw threadedly engaged with a male screw portion of the feed bar for feeding the cutting function portion 10, a cutting tool 13 for cutting the crank shaft CS, A tool holder 14 for fixing the tool holder 14, and a tool transfer tool 15 for adjusting the depth of processing by moving the tool holder 14 back and forth.

Here, the conveying bar is connected to the rotary ring 2, and is installed in parallel with the connecting bar 3, and has a male screw portion on its outer periphery. The tool holder 14 and the tool transfer tool 15 are connected through a screw connection so that when the tool transfer tool 15 is rotated, the tool holder 14 and the cutting tool 13 are moved forward or backward It is preferable to be configured to reverse.

The abrasive machining step is a step of grinding the crush shaft (CS) to be machined by installing the abrasive function part (20) in the crank shaft machining device (1).

5, the grinding function unit 20 includes a grinding portion bracket 21 having a coupling means such as a bolt coupled to the rotary ring 2 at one side thereof, a grinding portion bracket 21 having a grinding portion bracket 21, A driven bevel gear 23 coupled to a rotating shaft of the abrasive tool 22; a driven bevel gear 23 coupled to the driven bevel gear 23 by a gear- Side bevel gear 24 and a drive motor 25 coupled to the drive shaft to drive the drive motor 25. The power is transmitted from the drive shaft to the drive side bevel gear 24 ) -> driven side bevel gear 23 -> rotation shaft-> the polishing tool 22 to rotate the polishing tool 22 to grind the crankshaft CS.

The polishing step is a step of polishing the part to be machined of the crankshaft, which has been polished by installing the polishing function part (30) in the crankshaft working device (1).

6, the polishing function unit 30 includes a polishing unit bracket 31 having a coupling means such as a bolt coupled to the rotary ring 2 at one side thereof, And a polishing tool 32 supported by elastic means on the polishing tool 31. The polishing compound is put between the polishing tool 32 and the part to be processed and then polished while rotating the rotary ring.

The primary detection step is a process of measuring geometric requirements such as surface roughness, straightness, roundness, ovality, and taperness of a crankshaft (CS) subjected to polishing. If necessary, hardness measurement and the like can be performed for the subsequent secondary heat treatment.

The secondary heat treatment step is a process of performing a heat treatment to restore the hardness of a part to be processed of the crankshaft CS.

In this process, as in the first heat treatment step, the part to be processed is covered with the heat treatment mat, and the heat treatment is performed by heating and heating. Here, the heat treatment mat is connected to the temperature control device to control the power supply to obtain a desired hardness at the part to be processed

The secondary detection step is a step of measuring the surface roughness and hardness of the crankshaft (CS) subjected to the secondary heat treatment.

Through the above-described process, the crankshaft in-process method according to the present invention can process the crankshaft CS relatively easily and precisely and accurately without removing the crankshaft CS, And an excellent processing quality can be obtained.

1: crankshaft working device 2: rotating ring
3: Connection bar 4: Chain
5: Spracket 6: Motor
10: Cutting function part 11: Through hole
12: screw hole 13: cutting tool
14: Tool holder 15: Tool transfer tool
20: polishing function part 21: polishing part bracket
22: abrasive tool 23: driven side bevel gear
24: driving side bevel gear 25: driving motor
30: Polishing function part 31: Polishing part bracket
32: Polishing tool
CS: Crankshaft CP: Crank pin

Claims (5)

A step of preparing a machining apparatus for preparing a crankshaft machining apparatus for crankshaft machining,
A primary heat treatment step of performing a primary heat treatment in order to lower the hardness of the crankshaft processing target part,
A working target diameter calculating step of calculating a target diameter of the crankshaft,
An apparatus mounting step of mounting the crankshaft working apparatus to the crankshaft,
A cutting process step of providing a cutting function part to the crankshaft working device to cut the crankshaft to a target diameter of the crankshaft,
A polishing processing step of providing a polishing function part to the crankshaft working device to polish a machining target part of the crankshaft subjected to the cutting process,
A polishing processing step of polishing the crankshaft to be machined by installing a polishing function part in the crankshaft machining device,
A primary inspection step of measuring the surface roughness, straightness, and roundness of the crankshaft completed polishing,
A secondary heat treatment performing step of performing a heat treatment for restoring the hardness of the part to be processed of the crankshaft and
And a secondary inspection step of measuring the surface roughness and hardness of the crankshaft subjected to the secondary heat treatment.
Crankshaft in-process method
The method according to claim 1,
Wherein the heat treatment in the primary heat treatment step and the secondary heat treatment step is performed by covering a heat treatment mat on a part to be processed and the temperature is controlled by the temperature control device
Crankshaft in-process method
The method of claim 2,
The crankshaft working apparatus includes:
A pair of rotating rings formed on the outer circumference to be engaged with the chain,
A connecting bar in which the pair of rotating rings are coupled so as to maintain a constant spacing from each other; and
A chain wound around the rotary ring, and a motor coupled to the chain and having a sprocket for rotationally driving the chain.
Crankshaft in-process method
The method of claim 3,
The cutting function part
A pair of through holes through which the connecting bar passes for fixing to a connecting bar of the crankshaft working apparatus,
A screw hole having a female screw threadably engaged with a male screw portion of the feed bar for feeding the cutting function portion,
A cutting tool for cutting the crankshaft,
A tool holder for fixing the cutting tool, and a tool transfer tool for adjusting the machining depth by moving the tool holder back and forth
Crankshaft in-process method
The method of claim 3,
The polishing function unit
An abrasive portion bracket having a coupling means such as a bolt coupled to the rotary ring at one side thereof,
An abrasive tool supported on the abrasive portion bracket by a bearing and installed to be rotatable about a rotation axis,
A driven bevel gear coupled to a rotating shaft of the polishing tool,
A driven bevel gear which is gear-engaged with the driven bevel gear,
And the drive side bevel gear is coupled to the drive shaft.
Crankshaft in-process method
KR20130081341A 2013-07-11 2013-07-11 In-situ crankshaft reconditioning method KR20150008226A (en)

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Application Number Priority Date Filing Date Title
KR20130081341A KR20150008226A (en) 2013-07-11 2013-07-11 In-situ crankshaft reconditioning method

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Application Number Priority Date Filing Date Title
KR20130081341A KR20150008226A (en) 2013-07-11 2013-07-11 In-situ crankshaft reconditioning method

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KR20150008226A true KR20150008226A (en) 2015-01-22

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109352265A (en) * 2018-08-28 2019-02-19 浙江众立机械制造有限公司 A kind of propeller processing technique
CN111408989A (en) * 2020-04-23 2020-07-14 神龙汽车有限公司 Crankshaft follow-up deburring method
WO2022069072A1 (en) * 2020-10-01 2022-04-07 Caterpillar Motoren Gmbh & Co. Kg Method for repairing a component by heat treating
CN114473533A (en) * 2022-02-16 2022-05-13 无锡市通合机械有限公司 A few word roof beam shaping production line of subsidiary straightness accuracy detection
CN114473662A (en) * 2022-01-24 2022-05-13 库卡机器人(广东)有限公司 Crankshaft machining mechanism and crankshaft machining equipment

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109352265A (en) * 2018-08-28 2019-02-19 浙江众立机械制造有限公司 A kind of propeller processing technique
CN111408989A (en) * 2020-04-23 2020-07-14 神龙汽车有限公司 Crankshaft follow-up deburring method
WO2022069072A1 (en) * 2020-10-01 2022-04-07 Caterpillar Motoren Gmbh & Co. Kg Method for repairing a component by heat treating
CN114473662A (en) * 2022-01-24 2022-05-13 库卡机器人(广东)有限公司 Crankshaft machining mechanism and crankshaft machining equipment
CN114473662B (en) * 2022-01-24 2023-08-08 库卡机器人(广东)有限公司 Crankshaft machining mechanism and crankshaft machining equipment
CN114473533A (en) * 2022-02-16 2022-05-13 无锡市通合机械有限公司 A few word roof beam shaping production line of subsidiary straightness accuracy detection

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