CN110159447A - A kind of steel pistons and its hollow inner-cooling oil recess forming method - Google Patents
A kind of steel pistons and its hollow inner-cooling oil recess forming method Download PDFInfo
- Publication number
- CN110159447A CN110159447A CN201910585400.6A CN201910585400A CN110159447A CN 110159447 A CN110159447 A CN 110159447A CN 201910585400 A CN201910585400 A CN 201910585400A CN 110159447 A CN110159447 A CN 110159447A
- Authority
- CN
- China
- Prior art keywords
- annular groove
- insert
- piston body
- annular
- steel pistons
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- 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
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
- B23P15/10—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass pistons
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F3/00—Pistons
- F02F3/16—Pistons having cooling means
- F02F3/18—Pistons having cooling means the means being a liquid or solid coolant, e.g. sodium, in a closed chamber in piston
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F3/00—Pistons
- F02F2003/0007—Monolithic pistons; One piece constructions; Casting of pistons
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F2200/00—Manufacturing
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02F—CYLINDERS, PISTONS OR CASINGS, FOR COMBUSTION ENGINES; ARRANGEMENTS OF SEALINGS IN COMBUSTION ENGINES
- F02F2200/00—Manufacturing
- F02F2200/06—Casting
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- General Engineering & Computer Science (AREA)
- Pistons, Piston Rings, And Cylinders (AREA)
- Forging (AREA)
Abstract
The present invention discloses a kind of steel pistons, piston body including integral type, the annular groove around central axis is provided in the outer peripheral sidewall on piston body head, outside of the opening of annular groove radially toward piston body, it further include the insert of closed ring channel opening, there are spaces between insert and annular groove bottom, close hollow inner-cooling oil recess to be formed.Invention additionally discloses a kind of hollow inner-cooling oil recess forming method, the piston body including step forging molding integral type, machining surrounds the annular groove of central axis, the outside of the opening of annular groove radially toward piston body in the outer peripheral sidewall on piston body head；It processes insert and passes through insert closed ring channel opening, there are spaces between insert and annular groove bottom, close hollow inner-cooling oil recess to be formed.The junction of piston body and insert avoids piston high temperature stress concentration zones, prevents hot operation cracked, improves equipment intensity, simplifies process, does not need special type knife, and forming process is simple, improves working efficiency.
Description
Technical field
The present invention relates to engine components fields, more particularly to a kind of steel pistons.Moreover, it relates to a kind of steel
The hollow inner-cooling oil recess forming method of piston.
Background technique
With the continuous improvement of engine reinforcing degree, explosion pressure is higher and higher, is become using forging steel piston and solves to live
Fill in a kind of method of high load capacity problem.When forging steel piston blank forms, it cannot be formed cold in the piston as all-aluminium piston
Hollow oil pocket can only be obtained by processing, then form oil pocket by modes such as welding, cover plate for sealing, and current existing method is to add
Both work goes out ontology and ring shore point, and oil road is pre-machined, welded after combination, but weld metal zone is easy to appear crackle, segregation
And the defects of stomata, and cracked zone, just in the high temperature of piston and stress concentration region, intensity is lower.
Both or head and skirt section are processed, oil road is pre-machined, welded after combination, it will form in oil duct big
Overlap influences oil duct coolant liquid filling effect.Or the groove of opening axially downwardly is processed, it then covers and removably keeps off
Plate, but this mode groove must can accommodate the hook-shaped cutter of lower processing oil pocket, and while processing, does not generate interference, processing oil
Chamber complex process, it is not easy to produce in enormous quantities.
Therefore, how to provide a kind of simple and high-intensitive steel pistons of molding mode is that those skilled in the art need at present
The technical issues of solution.
Summary of the invention
The object of the present invention is to provide a kind of steel pistons, are formed by the insert of setting annular groove and closed ring slot hollow
Inner-cooling oil recess, improves intensity and molding mode is simple.It is a further object of the present invention to provide a kind of hollow inner-cooling oil recess of steel pistons
Forming method.
In order to solve the above technical problems, the present invention provides a kind of steel pistons, and the piston body including integral type, the piston body
The annular groove around central axis is provided in the outer peripheral sidewall on head, the opening of the annular groove is radially toward the piston
The outside of body further includes the insert for closing the annular channel opening, there are space between the insert and the annular groove bottom,
Hollow inner-cooling oil recess is closed to be formed.
Preferably, the insert is specially annular slab, and the radial section of the annular slab is the annular around central axis,
The thickness of the annular slab and the size of the annular channel opening match, so that the annular slab is embedded in the annular groove simultaneously
The annular groove is completely enclosed, the outer peripheral sidewall of the annular slab is concordant with the outer peripheral sidewall on the piston body head.
Preferably, the annular weight loss groove around central axis is provided on the inner circumferential side wall of the annular slab.
Preferably, the edges at two ends of the annular slab inner circumferential side wall is provided with the chimb to extend internally.
Preferably, the annular slab includes symmetrically arranged two and half ring flat-plate.
Preferably, half ring flat-plate and the junction of the junction of the annular groove and two half ring flat-plates pass through
High energy beam welding.
Preferably, the angle of the weld seam between two half ring flat-plates and the piston long axis of body is less than 45 degree.
The present invention provides a kind of forming method of steel pistons, comprising steps of
The piston body of forging molding integral type, machining surrounds central axis in the outer peripheral sidewall on the piston body head
The annular groove of line, the outside of the opening of the annular groove radially toward the piston body；
It processes insert and the annular channel opening is closed by the insert, between the insert and the annular groove bottom
There are spaces, close hollow inner-cooling oil recess to be formed.
Preferably, the processing insert and the annular channel opening is closed by the insert comprising steps of
Annular slab is processed, the radial section of the annular slab is the annular around central axis, the thickness of the annular slab
Match with the size of the annular channel opening；
Two and half ring flat-plates that the annular slab is cut into；
Two half ring flat-plates are embedded in the annular groove and completely enclose the annular groove, the periphery of half ring flat-plate
Side wall is concordant with the outer peripheral sidewall on the piston body head；
Pass through half ring flat-plate described in high energy beam welding and the junction of the annular groove and the connection of two half ring flat-plates
Place.
Preferably, the processing insert and the annular channel opening is closed by the insert comprising steps of
The insert, which is formed, by 3D printing closes the annular channel opening.
The present invention provides a kind of steel pistons, the piston body including integral type, is provided in the outer peripheral sidewall on piston body head
Around the annular groove of central axis, the opening of annular groove further includes closed ring channel opening radially toward the outside of piston body
Insert close hollow inner-cooling oil recess there are space between insert and annular groove bottom to be formed.
Specifically the hollow inner-cooling oil recess forming method of steel pistons comprising steps of forging molding integral type piston body, in work
Machining surrounds the annular groove of central axis in the outer peripheral sidewall on cock body head, and the opening of annular groove is radially toward piston body
Outside；It processes insert and passes through insert closed ring channel opening, there are spaces between insert and annular groove bottom, to form envelope
Close hollow inner-cooling oil recess.
By the setting to annular groove position and orientation, the junction of piston body and insert avoids piston high temperature stress collection
Middle area prevents hot operation cracked, improves equipment intensity, simplifies process, does not need special type knife, forming process letter
It is single, improve working efficiency.
Detailed description of the invention
Fig. 1 is a kind of structural schematic diagram of specific embodiment of steel pistons provided by the present invention；
Fig. 2 is the schematic front view of piston body in a kind of specific embodiment of steel pistons provided by the present invention；
Fig. 3 is the schematic side view of piston body in a kind of specific embodiment of steel pistons provided by the present invention；
Fig. 4 is the schematic front view of half ring flat-plate in a kind of specific embodiment of steel pistons provided by the present invention；
Fig. 5 is the schematic top plan view of half ring flat-plate in a kind of specific embodiment of steel pistons provided by the present invention；
Fig. 6 is a kind of top cross-sectional view of specific embodiment of steel pistons provided by the present invention.
Specific embodiment
Core of the invention is to provide a kind of steel pistons, is formed by the insert of setting annular groove and closed ring slot hollow
Inner-cooling oil recess, improves intensity and molding mode is simple.Another core of the invention is to provide a kind of hollow inner-cooling oil recess of steel pistons
Forming method.
In order to enable those skilled in the art to better understand the solution of the present invention, with reference to the accompanying drawings and detailed description
The present invention is described in further detail.
Fig. 1 to Fig. 6 is please referred to, Fig. 1 is a kind of structural representation of specific embodiment of steel pistons provided by the present invention
Figure；Fig. 2 is the schematic front view of piston body in a kind of specific embodiment of steel pistons provided by the present invention；Fig. 3 is this hair
The schematic side view of piston body in a kind of specific embodiment of steel pistons provided by bright；Fig. 4 is steel provided by the present invention
The schematic front view of half ring flat-plate in a kind of specific embodiment of piston；Fig. 5 is a kind of tool of steel pistons provided by the present invention
The schematic top plan view of half ring flat-plate in body embodiment；Fig. 6 is a kind of specific embodiment of steel pistons provided by the present invention
Top cross-sectional view.
The specific embodiment of the invention provides a kind of steel pistons, the piston body 1 including integral type, i.e. head and skirt section one
Formula setting, the end face on head are hot working face, and the end in skirt section is for connecting connecting rod etc., the outer peripheral sidewall on 1 head of piston body
On be provided with annular groove 11 around central axis, outside of the opening of annular groove 11 radially toward piston body 1, piston body 1
The end face on head is high temperature stress concentration zones, and it further includes what closed ring slot 11 was open that the position of annular groove 11, which avoids end face,
Insert, there are spaces between 11 bottom of insert and annular groove, close hollow inner-cooling oil recess 3 to be formed, set in 11 bottom of annular groove
It is equipped with disengaging oilhole.
The hollow inner-cooling oil recess forming method of steel pistons is the piston body 1 of forging molding integral type, in the outer of 1 head of piston body
Machining surrounds the annular groove 11 of central axis on all side walls, the opening of annular groove 11 radially toward piston body 1 outside,
And the shape of 11 bottom of annular groove is processed as needed, since opening is radially toward outside, in process, straight knife, which enters, is
Can, do not need special type knife.It processes insert and is open by insert closed ring slot 11, insert and annular groove are stayed between 11 bottom
There is space, closes hollow inner-cooling oil recess 3 to be formed.
By the setting to annular groove position and orientation, the junction of piston body and insert avoids piston high temperature stress collection
Middle area prevents hot operation cracked, improves equipment intensity, simplifies process, does not need special type knife, forming process letter
It is single, improve working efficiency.
In the steel pistons that the specific embodiment of the invention provides, insert is specially annular slab 2, and the radial direction of annular slab 2 is cut
Face is the annular around central axis, and the size that the thickness of annular slab 2 is open with annular groove 11 matches, so that annular slab 2 is embedding
Enter in annular groove 11 and completely enclosed annular groove 11, the i.e. both sides of the face of annular slab 2 and two sides of annular groove 11 closely connect
Touching, the outer peripheral sidewall of annular slab 2 is concordant with the outer peripheral sidewall on 1 head of piston body, so that piston is normally stretched, in annular slab 2
Step is provided in outer peripheral sidewall far from head one end.
Further, it is provided with the annular weight loss groove 22 around central axis on the inner circumferential side wall of annular slab 2, is guaranteeing wall
Loss of weight in the case where thickness saves material, increases oil pocket space., the edges at two ends of 2 inner circumferential side wall of annular slab, which is provided with, to extend internally
Chimb 23, with annular groove 11 formed oil closed cavity, can also according to circumstances adjust the quantity and arrangement of ring stiffener 22,
It is within the scope of the present invention.
On the basis of the steel pistons that above-mentioned each specific embodiment provides, annular slab 2 includes symmetrically arranged two and half
Ring flat-plate 21, is easily installed, and is a complete annular slab 2 after the docking of two and half ring flat-plates 21.It can also be according to circumstances by annular slab 2
It is divided into more parts, such as three or four, it is within the scope of the present invention.
Wherein, half ring flat-plate 21 is welded by high energy beam with the junction of annular groove 11 and the junction of two and half ring flat-plates 21
It connects, improves welding effect, guarantee is stably connected with and sealing effect, while the flowing for avoiding the occurrence of overlap and influencing cooling oil is imitated
Fruit.
The angle of weld seam 23 and 1 long axis 12 of piston body between two and half ring flat-plates 21 avoids stress from concentrating, mentions less than 45 degree
It is high-intensitive.
Specifically, process insert and make insert closed ring slot 11 be open comprising steps of
Preprocessing annular slab 2 makes the radial section of annular slab 2 around the annular of central axis, the thickness of annular slab 2 with
The size that annular groove 11 is open matches；Two and half ring flat-plates 21 that annular slab 2 is cut into；Two and half ring flat-plates 21 are embedded in annular
The docking of latter two half ring flat-plate 21 forms a complete annular slab 2 in slot 11, makes completely enclosed annular groove 11, outside half ring flat-plate 21
All side walls are concordant with the outer peripheral sidewall on 1 head of piston body；By the junction of half ring flat-plate 21 of high energy beam welding and annular groove 11 with
And two and half ring flat-plate 21 junction.
Other modes processing insert can also be used and insert closed ring slot 11 is made to be open, insert is such as formed by 3D printing
Closed ring slot 11 is open, that is, does not need 2 structure of annular slab, directly close to annular groove 11, in protection of the invention
Within the scope of.
Steel pistons provided by the present invention and its hollow inner-cooling oil recess forming method are described in detail above.Herein
In apply that a specific example illustrates the principle and implementation of the invention, the explanation of above example is only intended to sides
Assistant solves method and its core concept of the invention.It should be pointed out that for those skilled in the art, not
, can be with several improvements and modifications are made to the present invention under the premise of being detached from the principle of the invention, these improvement and modification are also fallen into
In the protection scope of the claims in the present invention.
Claims (10)
1. a kind of steel pistons, the piston body (1) including integral type, which is characterized in that the outer peripheral sidewall on piston body (1) head
On be provided with annular groove (11) around central axis, the opening of the annular groove (11) is radially toward the piston body (1)
Outside, further include close the annular groove (11) opening insert, stayed between the insert and the annular groove (11) bottom
There is space, closes hollow inner-cooling oil recess (3) to be formed.
2. steel pistons according to claim 1, which is characterized in that the insert is specially annular slab (2), the annular slab
(2) radial section is the annular around central axis, the ruler of the thickness of the annular slab (2) and the annular groove (11) opening
It is very little to match, so that the annular slab (2) is embedded in the annular groove (11) and completely encloses the annular groove (11), the ring
The outer peripheral sidewall of shape plate (2) is concordant with the outer peripheral sidewall on the piston body (1) head.
3. steel pistons according to claim 2, which is characterized in that be provided with and enclose on the inner circumferential side wall of the annular slab (2)
Around the annular weight loss groove (22) of central axis.
4. steel pistons according to claim 3, which is characterized in that the edges at two ends of annular slab (2) the inner circumferential side wall is set
It is equipped with the chimb (23) to extend internally.
5. according to steel pistons described in claim 2 to 4 any one, which is characterized in that the annular slab (2) includes symmetrically setting
Two and half ring flat-plates (21) set.
6. steel pistons according to claim 5, which is characterized in that the company of half ring flat-plate (21) and the annular groove (11)
The place of connecing and the junction of two half ring flat-plates (21) pass through high energy beam welding.
7. steel pistons according to claim 6, which is characterized in that weld seam (23) between two half ring flat-plates (21) with
The angle of piston body (1) long axis (12) is less than 45 degree.
8. a kind of hollow inner-cooling oil recess forming method of steel pistons, which is characterized in that comprising steps of
The piston body (1) of forging molding integral type, machining surrounds center in the outer peripheral sidewall on the piston body (1) head
The annular groove (11) of axis, the outside of the opening of the annular groove (11) radially toward the piston body (1)；
It processes insert and the annular groove (11) is closed by the insert and be open, the insert and the annular groove (11) bottom
Between there are space, close hollow inner-cooling oil recess (3) to be formed.
9. the hollow inner-cooling oil recess forming method of steel pistons according to claim 8, which is characterized in that the processing insert is simultaneously
Close the annular groove (11) opening by the insert comprising steps of
It processes annular slab (2), the radial section of the annular slab (2) is the annular around central axis, the annular slab (2)
The size that thickness is open with the annular groove (11) matches；
Two and half ring flat-plates (21) that the annular slab (2) is cut into；
Two half ring flat-plates (21) are embedded in the annular groove (11) and completely enclose the annular groove (11), the semi-ring
The outer peripheral sidewall of plate (21) is concordant with the outer peripheral sidewall on the piston body (1) head；
Pass through the junction and two half ring flat-plates of half ring flat-plate (21) described in high energy beam welding and the annular groove (11)
(21) junction.
10. the hollow inner-cooling oil recess forming method of steel pistons according to claim 8, which is characterized in that the processing insert
And the annular groove (11) opening closed by the insert comprising steps of
The insert, which is formed, by 3D printing closes annular groove (11) opening.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910585400.6A CN110159447A (en) | 2019-07-01 | 2019-07-01 | A kind of steel pistons and its hollow inner-cooling oil recess forming method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910585400.6A CN110159447A (en) | 2019-07-01 | 2019-07-01 | A kind of steel pistons and its hollow inner-cooling oil recess forming method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110159447A true CN110159447A (en) | 2019-08-23 |
Family
ID=67637229
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910585400.6A Withdrawn CN110159447A (en) | 2019-07-01 | 2019-07-01 | A kind of steel pistons and its hollow inner-cooling oil recess forming method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110159447A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111237079A (en) * | 2020-03-11 | 2020-06-05 | 滨州东海龙活塞有限公司 | Ring bank welding integral forged steel piston and machining method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02157461A (en) * | 1988-12-12 | 1990-06-18 | Mitsubishi Heavy Ind Ltd | Piston for internal combustion engine |
| CN1535191A (en) * | 2001-07-30 | 2004-10-06 | С | Method for mounting a sheet metal ring assembled and welded in a load-bearing collar for fitting to an annular cooling tube of a piston of an internal combustion engine, and resulting sheet metal ring |
| CN107084069A (en) * | 2017-05-22 | 2017-08-22 | 无锡华星机电制造有限公司 | A kind of engine piston |
| CN207261119U (en) * | 2017-08-24 | 2018-04-20 | 叶长青 | A kind of Split piston |
| CN109931178A (en) * | 2017-12-19 | 2019-06-25 | 强莉莉 | A kind of piston and its forming method |
-
2019
- 2019-07-01 CN CN201910585400.6A patent/CN110159447A/en not_active Withdrawn
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH02157461A (en) * | 1988-12-12 | 1990-06-18 | Mitsubishi Heavy Ind Ltd | Piston for internal combustion engine |
| CN1535191A (en) * | 2001-07-30 | 2004-10-06 | С | Method for mounting a sheet metal ring assembled and welded in a load-bearing collar for fitting to an annular cooling tube of a piston of an internal combustion engine, and resulting sheet metal ring |
| CN107084069A (en) * | 2017-05-22 | 2017-08-22 | 无锡华星机电制造有限公司 | A kind of engine piston |
| CN207261119U (en) * | 2017-08-24 | 2018-04-20 | 叶长青 | A kind of Split piston |
| CN109931178A (en) * | 2017-12-19 | 2019-06-25 | 强莉莉 | A kind of piston and its forming method |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111237079A (en) * | 2020-03-11 | 2020-06-05 | 滨州东海龙活塞有限公司 | Ring bank welding integral forged steel piston and machining method thereof |
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| PB01 | Publication | ||
| PB01 | Publication | ||
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Application publication date: 20190823 |