阅读说明：本技术 一种细长孔的精密加工件及其制造方法 (Precision machined part of elongated hole and manufacturing method thereof ) 是由 钱吉治 何林芳 廖庆云 潘桔生 于 2019-11-04 设计创作，主要内容包括：本发明公开了一种细长孔的精密加工件及其制造方法,包括柱体套件,所述柱体套件由内套和热套在内套外部的外套构成,位于所述内套的外表壁开设有竖直分布的外半圆槽,位于所述外套的内表壁开设有内半圆槽。本发明中,发动机缸体有内套和外套热套构成,内套外表壁开设外半圆槽,外套内表壁开设内半圆槽,内套和外套热套后外半圆槽和内半圆槽形成一个完成的预留孔,便于后续的钻头扩孔和铰刀铰孔加工,降低钻刀的报废率和发动机缸体的报废率,发动机缸体对应的制造方法为先单独加工内套和外套然后进行正火降低硬度,最后将内套和外套对接后利用摩擦融合成一体,提高整个发动机缸体的气密性,制作简单,成本低。(The invention discloses a precision machined part of a slender hole and a manufacturing method thereof. According to the engine cylinder body, the inner sleeve and the outer sleeve are arranged, the outer surface wall of the inner sleeve is provided with the outer semicircular groove, the inner surface wall of the outer sleeve is provided with the inner semicircular groove, the outer semicircular groove and the inner semicircular groove form a finished reserved hole after the inner sleeve and the outer sleeve are sleeved in a hot mode, subsequent drill reaming and reamer reaming are facilitated, the rejection rate of a drill bit and the rejection rate of the engine cylinder body are reduced, the engine cylinder body is manufactured correspondingly.)

1. The utility model provides a fine machined part of elongated hole, includes the cylinder external member, its characterized in that, the cylinder external member comprises endotheca (1) and hot jacket overcoat (2) outside endotheca (1), is located the exterior wall of endotheca (1) is seted up outer half slot (11) of vertical distribution, is located interior half slot (21) have been seted up to the interior surface wall of overcoat (2), interior half slot (21) and outer half slot (11) constitute one preformed hole (3) of accomplishing.

2. Precision machining part for elongated holes according to claim 1, characterized in that integral external limiting protrusions (22) are fixedly arranged on the outer surface wall of the outer sleeve (2), and the external limiting protrusions (22) are uniformly distributed in the circumferential direction.

3. The precision machining piece for the elongated holes is characterized in that an integrated inner limiting bulge (12) is fixedly arranged on the inner surface wall of the inner sleeve (1), and the inner limiting bulge (12) is uniformly distributed in the circumferential direction.

4. Precision machining piece for elongated holes, according to claim 1, characterized in that the end of the outer sleeve (2) is fixedly provided with an integrated limit ring plate (23), the inner diameter of the limit ring plate (23) is the same as the inner diameter of the inner sleeve (1).

5. The method for manufacturing a precision workpiece for an elongated hole according to claim 1, comprising the steps of:

step one, blanking: selecting cylindrical rough blanks, and processing the rough blanks of the inner sleeve (1) and the outer sleeve (2) by linear cutting, wherein the processing allowance reserved on the inner and outer surface walls of the inner sleeve (1) and the outer sleeve (2) is 1.5-2.5 mm.

Step two, softening: and (3) annealing the inner sleeve (1) and the outer sleeve (2) obtained in the step two, wherein the annealing temperature is 620-632 ℃, and the annealing time is 1-1.5 h.

Step three, machining a matching surface: the outer surface wall of the inner sleeve (1) and the inner surface wall of the outer sleeve (2) are roughly machined to be the nominal diameter, and the outer surface wall and the inner surface wall are in transition fit.

Step four, grooving: roughly milling the outer surface wall of the inner sleeve (1) and the inner surface wall of the outer sleeve (2) by using a formed milling cutter to form a semicircular groove, and reserving a machining allowance, wherein the machining allowance is 0.3-0.5 mm.

Step five, fusion: the outer surface wall of the inner sleeve (1) and the inner surface wall of the outer sleeve (2) are connected in a nested manner, then the inner sleeve and the outer sleeve rotate in a staggered manner, the relative rotation speed is kept at 800-.

Step six, processing the elongated holes:

a. drilling a round hole formed by the semicircular groove at the rotating speed of 420-,

b. then reaming is carried out, the hole produced in the step a is processed at the cutting speed of 355 and 365r/min by using a reamer, and the feeding amount is 0.5-1.5 mm/r.

6. The method for manufacturing precision machined parts of elongated holes as claimed in claim 5, characterized in that in the third step, the outer circles of the inner surface wall of the inner sleeve (1) and the outer surface wall of the outer sleeve (2) are roughly turned, and the outer limit protrusions (12) and the outer limit protrusions (22) are reserved correspondingly.

7. The method for manufacturing precision machined parts of elongated holes as claimed in claim 5, characterized in that in the fourth step, the outer half-round slot (11) on the inner sleeve (1) is grooved by a flat milling cutter and then formed by a ball milling cutter, and the inner half-round slot (21) on the outer sleeve (2) is grooved by a broach and then formed by a cylindrical milling cutter.

8. The method for manufacturing precision workpieces of elongated holes as claimed in claim 5, wherein in the sixth step, the reamer used is a floating reamer made of cemented carbide.

Technical Field

The invention relates to the technical field of compact machined parts and manufacturing thereof, in particular to a precision machined part of an elongated hole and a manufacturing method thereof.

Background

Precision workpieces are key parts of parts, and in order to satisfy performance, a machine tool is generally used to perform rough machining.

The end of a workpiece such as an engine cylinder block is usually processed with a slender hole, and the fine processing of the workpiece of the slender hole is difficult, and the current processing mode is to drill a central hole, drill a hole, enlarge a hole and ream the hole at the end of a forming cylinder block, but the process has the following problems: 1. the cutter corresponding to the elongated hole is elongated and is easy to break, 2, the manufacturing cost of the cylinder body type workpiece blank is high, the resistance is high when the elongated cutter is used for reaming and drilling, the problem that the coaxiality of the elongated hole is unqualified is easy to occur, the rejection rate is high, and the production waste is large; 3. the machining process of drilling the center hole, drilling, expanding and reaming is adopted, the machining process is more, hole machining errors caused by accumulated tool setting easily occur, and the precision is low.

Accordingly, the present invention provides a precision machined part of an elongated hole and a method for manufacturing the same

Disclosure of Invention

The invention aims to: the precision machining part of the slender hole and the manufacturing method thereof are provided in order to solve the problems that the rejection rate of the engine cylinder body is high due to the fact that the slender hole is machined in the precision part of the engine cylinder body, and a cutter is easy to damage and machining precision is low due to the existing machining process.

In order to achieve the purpose, the invention adopts the following technical scheme:

the utility model provides a fine processing spare of elongated hole, includes the cylinder external member, the cylinder external member comprises endotheca and heat jacket at the outside overcoat of endotheca, is located the outer half slot of vertical distribution is seted up to the outward appearance wall of endotheca, is located interior half slot has been seted up to the interior surface wall of overcoat, interior half slot and outer half slot constitute a preformed hole of accomplishing.

As a further description of the above technical solution:

and the outer surface wall of the outer sleeve is fixedly provided with an integrated outer limiting bulge, and the outer limiting bulge is circumferentially and uniformly distributed.

As a further description of the above technical solution:

and the inner surface wall of the inner sleeve is fixedly provided with an integrated inner limiting bulge, and the inner limiting bulge is circumferentially and uniformly distributed.

As a further description of the above technical solution:

the end part of the outer sleeve is fixedly provided with an integrated limiting ring plate, and the inner diameter of the limiting ring plate is the same as that of the inner sleeve.

A method for manufacturing a precision machined part of an elongated hole comprises the following steps:

step one, blanking: selecting cylindrical blank blanks, and processing the blank blanks of the inner sleeve and the outer sleeve by linear cutting, wherein the processing allowance reserved on the inner and outer surface walls of the inner sleeve and the outer sleeve is 1.5-2.5 mm.

Step two, softening: and (4) annealing the inner sleeve and the outer sleeve obtained in the step two, wherein the annealing temperature is 620-632 ℃, and the annealing time is 1-1.5 h.

Step three, machining a matching surface: the outer surface wall of the inner sleeve and the inner surface wall of the outer sleeve are roughly machined to be the nominal diameter, and the inner surface wall and the outer surface wall are in transition fit.

Step four, grooving: roughly milling the outer surface wall of the inner sleeve and the inner surface wall of the outer sleeve by using a forming milling cutter to form a semicircular groove, and reserving a machining allowance, wherein the machining allowance is 0.3-0.5 mm.

Step five, fusion: nesting and connecting the outer surface wall of the inner sleeve and the inner surface wall of the outer sleeve, then rotating in a staggered manner, keeping the relative rotating speed at 800-.

Step six, processing the elongated holes:

a. drilling a round hole formed by the semicircular groove at the rotating speed of 420-,

b. then reaming is carried out, the hole produced in the step a is processed at the cutting speed of 355 and 365r/min by using a reamer, and the feeding amount is 0.5-1.5 mm/r.

As a further description of the above technical solution:

and in the third step, firstly, roughly turning the outer circles of the inner surface wall and the outer surface wall of the outer sleeve, and correspondingly reserving an outer inner limiting bulge and an outer limiting bulge.

As a further description of the above technical solution:

and in the fourth step, slotting the outer semicircular groove on the inner sleeve by adopting a flat milling cutter, then forming and processing by using a ball milling cutter, slotting the inner semicircular groove on the outer sleeve by using a broach, and then forming and processing by using a column milling cutter.

As a further description of the above technical solution:

in the sixth step, the reamer used is a floating reamer made of hard alloy.

In summary, due to the adoption of the technical scheme, the invention has the beneficial effects that:

1. according to the engine cylinder body, the inner sleeve and the outer sleeve are arranged, the outer surface wall of the inner sleeve is provided with the outer semicircular groove, the inner surface wall of the outer sleeve is provided with the inner semicircular groove, the outer semicircular groove and the inner semicircular groove form a finished reserved hole after the inner sleeve and the outer sleeve are sleeved in a hot mode, subsequent drill reaming and reamer reaming are facilitated, the rejection rate of a drill bit and the rejection rate of the engine cylinder body are reduced, the engine cylinder body is manufactured correspondingly.

2. According to the invention, the inner surface wall of the inner sleeve is provided with the inner limiting bulge, and the outer surface wall of the outer sleeve is provided with the outer limiting bulge, so that when the outer surface wall of the inner sleeve and the inner surface wall of the outer sleeve are processed, the two limiting bulges are convenient to clamp and position, and meanwhile, when friction melting matching is adopted, the clamping force can be increased, the phenomena of clamping deformation and slipping are avoided, and the precision of forming a finished reserved hole by the outer semicircular groove and the inner semicircular groove is improved.

3. In the invention, after the inner sleeve and the outer sleeve are nested, the machining resistance is reduced, the machining process is simplified and the machining efficiency is improved by reaming and reaming by the floating reamer.

Drawings

FIG. 1 is a schematic diagram of a matching structure of an inner sleeve and an outer sleeve of a precision machining piece with an elongated hole according to the present invention;

FIG. 2 is a schematic top view of the inner sleeve and the outer sleeve of the fine machined part with elongated holes according to the present invention;

FIG. 3 is a schematic diagram of a top view of an inner sleeve of a precision machined part with an elongated hole according to the present invention;

FIG. 4 is a flow chart of a method for manufacturing a precision machined part with an elongated hole according to the present invention;

fig. 5 is a flow chart of the grooving process of the method for manufacturing a precision machined part of an elongated hole according to the present invention.

Illustration of the drawings:

1. an inner sleeve; 11. an outer semicircular groove; 12. an inner limiting bulge; 2. a jacket; 21. an inner semicircular groove; 22. an outer limit bulge; 23. a limit ring plate; 3. holes are reserved.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.