阅读说明：本技术 一种三辊斜轧/穿孔复合成形空心阶梯轴方法 (Method for forming hollow stepped shaft by three-roller skew rolling/punching combination ) 是由 束学道 张松 陈友华 于 2020-04-14 设计创作，主要内容包括：本发明涉及塑性成形技术领域,尤其涉及一种三辊斜轧/穿孔复合成形空心阶梯轴方法。它包括斜轧机,斜轧机上设有推料机及芯棒,芯棒的轴线与斜轧机的加工轴线同轴布置,斜轧机上沿斜轧机的加工轴线上前后布置有一级斜轧辊及二级斜轧辊,且一级斜轧辊的轴线和二级斜轧辊的轴线与斜轧机的加工轴线之间均具有偏转角,一级斜轧辊沿其自身轴线转动,二级斜轧辊沿其自身轴线转动且沿圆棒料的径向移动,所述推料机用于推送圆棒料使圆棒料依次经过一级斜轧辊及二级斜轧辊,具体步骤包括推料-穿孔-阶梯成形-抽芯棒,本发明能通过一个工序加工出空心阶梯轴,减少加工流程,节约加工时间。(The invention relates to the technical field of plastic forming, in particular to a method for compositely forming a hollow stepped shaft by three-roller skew rolling/perforation. The hollow stepped shaft processing device comprises a diagonal mill, wherein a pusher and a mandrel are arranged on the diagonal mill, the axis of the mandrel and the processing axis of the diagonal mill are coaxially arranged, a first-stage diagonal roll and a second-stage diagonal roll are arranged on the diagonal mill along the processing axis of the diagonal mill in a front-back manner, deflection angles are respectively arranged between the axis of the first-stage diagonal roll and the axis of the second-stage diagonal roll and the processing axis of the diagonal mill, the first-stage diagonal roll rotates along the axis of the first-stage diagonal roll, the second-stage diagonal roll rotates along the axis of the second-stage diagonal roll and moves along the radial direction of a round bar, the pusher is used for pushing the round bar to enable the round bar to sequentially pass through the first-stage diagonal roll and the second-stage diagonal roll, and the concrete steps comprise pushing, perforating, stepped.)

1. A method for compositely forming a hollow stepped shaft by three-roller skew rolling/punching is characterized by comprising a skew rolling mill, wherein a pusher and a mandrel are arranged on the skew rolling mill, the axis of the mandrel is coaxially arranged with the processing axis of the skew rolling mill, a first-stage skew roller and a second-stage skew roller are arranged on the skew rolling mill along the processing axis of the skew rolling mill in a front-back manner, deflection angles are respectively arranged between the axis of the first-stage skew roller and the axis of the second-stage skew roller and the processing axis of the skew rolling mill, the first-stage skew roller rotates along the axis of the first-stage skew roller, the second-stage skew roller rotates along the axis of the second-stage skew roller and moves along the radial direction of a round bar, and the pusher is used for pushing:

firstly, a pusher clamps a high-temperature round bar material and pushes the high-temperature round bar material into a skew rolling mill along the processing axis of the skew rolling mill;

secondly, the first-stage inclined roller bites the round bar and pushes the round bar to rotate and move forwards along the processing axis of the inclined rolling mill, and the mandrel punches the round bar;

and thirdly, after the round bar stock is punched, the secondary roller enables the round bar stock to form a step shape through radial movement.

2. The method for three-roll skew rolling/piercing combined forming of the hollow stepped shaft according to claim 1, wherein the third step is followed by the steps of:

and fourthly, extracting the core rod from the formed round bar stock.

3. The method as claimed in claim 2, wherein the skew rolling mill is provided with a U-shaped stopper through which the mandrel passes, the U-shaped stopper stopping the formed round bar so that the mandrel can be withdrawn from the formed round bar.

4. A method of three-roll skew/bore composite forming of hollow stepped shafts as claimed in claim 2 or claim 3, wherein a hydraulic clamp is used to grip one end of the mandrel and to withdraw it from the formed round bar stock.

5. The method for three-roll skew rolling/piercing combined forming of the hollow stepped shaft according to claim 1, 2 or 3, wherein the contact area of the primary skew roll and the round bar stock is larger than the contact area of the secondary skew roll and the round bar stock.

6. The method for three-roll skew rolling/piercing combined forming of the hollow stepped shaft according to claim 5, wherein the primary skew roll is barrel-shaped, the secondary skew roll is disk-shaped, the diameter of the primary skew roll decreases from the middle to both ends, and the diameter of the secondary skew roll gradually increases from one end to the other end.

7. The method for three-roll skew/piercing combined forming of a hollow stepped shaft according to claim 1, 2 or 3, wherein the end of the core rod facing the round bar is conical.

Technical Field

The invention relates to the technical field of plastic forming, in particular to a method for compositely forming a hollow stepped shaft by three-roller skew rolling/perforation.

Background

The cross wedge rolling technology is used for rolling shaft products and has unique advantages, the material utilization rate is high, the forming speed is high, and people pay more and more attention in recent years, but the production technology of cross wedge rolling of some special products is still to be developed, for example, hollow stepped shafts, because the cross wedge rolling processing shaft parts is characterized in that the cross wedge rolling processing shaft parts rotate to extrude plastic forming, when the hollow stepped shafts are processed, inner holes must be processed on round bars in advance, core rods are plugged into the inner holes, the workpieces are taken down after the processing on a double-roller mill is completed, the core rods are taken out and separated from the inner holes, the working procedures are increased, and the production efficiency is reduced.

For example, a forming method is disclosed in a patent with Chinese patent No. CN1016588588, the grant publication date is 2011.04.20, the invention name is 'a method for forming a hollow shaft head blank of an automobile rear axle by cross wedge rolling', a round seamless steel pipe is heated to 800-1100 ℃, a mandrel is penetrated, and the steel pipe with the mandrel is sent between two roller type dies by an axial pushing device. The die is provided with two pairs of wedges, a steel pipe is firstly rolled under the action of the first pair of wedges, then the steel pipe is pushed into the second pair of wedges by the axial pushing device, when the die rotates for a second circle, the axial automatic positioning of a rolled piece is realized by depending on the initial section of the second pair of wedges, then the whole rolled piece is rolled and formed, and the production of a blank of the hollow shaft head of the rear axle of the automobile is completed every two circles.

The forming method still has the problems that a plurality of processes are needed to be matched when the hollow stepped shaft is rolled by adopting the cross wedge rolling technology, the process flow is prolonged, and the production efficiency is greatly reduced.

Disclosure of Invention

The invention aims to overcome the defects that a plurality of processes are required to be matched when a hollow stepped shaft is rolled by adopting a cross wedge rolling technology in the prior art, the process flow is prolonged, and the production efficiency is greatly reduced.

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

a method for compositely forming a hollow stepped shaft by three-roller skew rolling/punching comprises a skew rolling machine, wherein a pusher and a mandrel are arranged on the skew rolling machine, the axis of the mandrel and the processing axis of the skew rolling machine are coaxially arranged, a first-stage skew roller and a second-stage skew roller are arranged on the skew rolling machine along the processing axis of the skew rolling machine in a front-back manner, deflection angles are respectively arranged between the axis of the first-stage skew roller and the axis of the second-stage skew roller and the processing axis of the skew rolling machine, the first-stage skew roller rotates along the axis of the first-stage skew roller, the second-stage skew roller rotates along the axis of the second-stage skew roller and moves along the radial direction of a round bar, the pusher is used for pushing the round:

firstly, a pusher clamps a high-temperature round bar material and pushes the high-temperature round bar material into a skew rolling mill along the processing axis of the skew rolling mill;

secondly, the first-stage inclined roller bites the round bar and pushes the round bar to rotate and move forwards along the processing axis of the inclined rolling mill, and the mandrel punches the round bar;

and thirdly, after the round bar stock is punched, the secondary roller enables the round bar stock to form a step shape through radial movement.

The invention processes the hollow stepped shaft by a procedure, which is mainly divided into 3 stages: pushing materials (step one), perforating (step two) and step forming (step three), wherein the three first-stage inclined rollers and the three second-stage inclined rollers are uniformly distributed around the processing axis of the inclined rolling mill and deflect a certain angle with the processing axis. The first-stage inclined roller only rotates around the axis of the first-stage inclined roller, mainly aims to bite the round bar and forwards pushes the round bar to enable the core rod to perforate the round bar, and the second-stage inclined roller rotates around the axis of the second-stage inclined roller and moves along the radial direction of the round bar to roll a step. Therefore, the round bar stock is formed into the hollow stepped shaft through a complete process of pushing, perforating and stepped forming on the skew rolling mill, compared with the prior art, the forming process is reduced, the processing time is saved, and the production efficiency is greatly increased.

Preferably, the third step is followed by the steps of: and fourthly, extracting the core rod from the formed round bar stock. And after the hollow stepped shaft is formed, a core-pulling rod process is continuously added to complete the separation of the hollow stepped shaft.

Preferably, the skew rolling mill is provided with a U-shaped stop, the mandrel passes through the U-shaped stop, and the U-shaped stop stops the formed round bar stock so that the mandrel can be extracted from the formed round bar stock. The U-shaped groove of the U-shaped stop block can enable the core rod to pass through, but cannot enable the hollow stepped shaft to pass through, so that the U-shaped stop block serves as a barrier, and the core rod in the hollow stepped shaft can be conveniently drawn out.

Preferably, a hydraulic caliper is used to grip one end of the mandrel and withdraw it from the formed round bar stock.

Preferably, the contact area of the first-stage inclined roller and the round bar is larger than that of the second-stage inclined roller and the round bar. The first-stage skew roller is mainly used for increasing the contact area between the first-stage skew roller and the round bar, so that the force for advancing the round bar is larger, the round bar can be conveniently perforated, the contact area between the second-stage skew roller and the round bar is small, the fluidity of materials on the round bar can be increased, and the step forming is convenient.

Preferably, the primary inclined roller is barrel-shaped, the secondary inclined roller is disc-shaped, the diameter of the primary inclined roller is reduced from the middle to two ends, and the diameter of the secondary inclined roller is gradually increased from one end to the other end. The one-level oblique roll of tubbiness can interlock round bar better, and the circular second grade oblique roll of discoid can carry out moulding to round bar better.

Preferably, the end of the core rod facing the round bar stock is conical. One end of the core rod is in a sharp conical shape, so that the round bar stock is favorably perforated.

The invention has the beneficial effects that: a hollow stepped shaft is processed through a working procedure, which is mainly divided into 4 stages: 4 stages of pushing, perforating, step forming and core pulling can be continuously completed on a skew rolling mill, the hollow step shaft is directly formed, the processing flow is reduced, the processing time is saved, and the production efficiency is greatly increased.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the following drawings without inventive labor.

FIG. 1 is a schematic view of the skew rolling mill according to the present invention;

FIG. 2 is a schematic view of the skew rolling mill according to another view of the present invention

FIG. 3 is a partial structural view of the round bar stock in the present invention.

Reference numerals: the device comprises a pusher 1, a core rod 2, a primary inclined roller 3, a secondary inclined roller 4, a round bar 5 and a U-shaped stop block 6.

Detailed Description

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may comprise the first and second features being in direct contact, or may comprise the first and second features being in contact, not directly, but via another feature in between. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

The method for three-roll skew rolling/piercing composite forming of a hollow stepped shaft according to an embodiment of the present invention will be described below with reference to the accompanying drawings.