CN102615221B - Radial and axial rolling forming method for large-sized double-groove ring piece - Google Patents

Radial and axial rolling forming method for large-sized double-groove ring piece Download PDF

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Publication number
CN102615221B
CN102615221B CN201110414446.5A CN201110414446A CN102615221B CN 102615221 B CN102615221 B CN 102615221B CN 201110414446 A CN201110414446 A CN 201110414446A CN 102615221 B CN102615221 B CN 102615221B
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rolling
ring
axial
radial
radius
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CN201110414446.5A
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Chinese (zh)
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CN102615221A (en
Inventor
钱东升
时大方
华林
汪小凯
张挺
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天马轴承集团股份有限公司
武汉理工大学
浙江天马轴承有限公司
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Abstract

The invention relates to a radial and axial rolling forming method for a large-sized double-groove ring piece. The method mainly comprises the following steps: (1), manufacturing blanks: uniformly heating the bar section to the hot forging deformation temperature, unsetting, piercing and punching the hot material section on a press to manufacture ring piece blanks, wherein the size of each ring piece blank is determined according to the ring piece size, the rolling ratio and the radial and axial feeding quantity ratio; (2), designing a rolling hole shape, wherein the rolling hole shape consists of a driving roller working surface and a core roller working surface and the size of the driving roller working surface and the core roller working surface is determined according to the rolling linear velocity, the equipment parameters, the rolling deformation condition, the size of the ring piece blank and the size of the ring piece; and (3), rolling and forming: placing the ring piece blank on a ring rolling machine and rolling, wherein the rolling process is controlled by reasonably distributing feeding speed and feeding quantity according to three stages of prerolling, primary rolling and shaping rolling and the rolling process is finished when the outer diameter of the ring piece reaches the preset value. The method has the characteristics of high production efficiency, low production cost and high product quality.

Description

A kind of large-scale pair of groove ring radial-axial rolling manufacturing process

Technical field

The present invention relates to a kind of large-scale pair of groove ring radial-axial rolling manufacturing process.

Background technology

Diameter surpasses 1 meter, and inner surface, with large-scale pair of groove ring of symmetrical groove, as rotating support ring, large-scale bearing ring etc., is widely used at engineering machinery, harbour machinery, wind power plant etc.This type of ring condition of work is severe, bears for a long time low temperature, heavy duty, HI high impact etc., and its performance and used life is had relatively high expectations.Ring radial-axial rolling (shown in Fig. 1) is a kind of advanced plastic working technique of producing large ring, and it is out of shape and can be obtained the high-quality large ring that geometric accuracy is high, structure property is good within a short period of time by continuous local plastic.Yet, ring radial-axial rolling process is the complex deformation process under the coupling of Alternative parameter, rolling technological parameter design and process control difficulty are large, especially for ring with odd-shaped cross section rolling, easily because process parameters design or process control are unreasonable, while causing ring diameter to reach dimensional requirement, cross section profile can not be full of, even cause the operation of rolling unstable, form rolling defect, useless, defect rate is higher.Therefore, most large scale special-shaped section ring parts are all first to pass through the orthogonal section ring parts of radial-axial rolling at present, then cut out cross section profile, and above-mentioned large-scale pair of groove ring be like this.By machine cut, process groove, cutting material loss and machining period consumption are large, and two groove processing precision are difficult to be consistent, and machining destroyed ring metal streamline and distribute, reduced ring mechanical performance, thereby caused production efficiency low, cost is high, and quality and life-span are difficult to guarantee.

Summary of the invention

For above-mentioned deficiency, the object of the present invention is to provide a kind of large-scale pair of trench cross section ring radial-axial rolling manufacturing process, by reasonable design rolling technological parameter and the optimization operation of rolling, can realize by square-section ring blank Direct Rolling and be configured as two groove rings, groove machining material and expenditure of time have significantly been reduced, and can obtain good metal streamline and distribute, improve production efficiency and product quality, reduce production cost.

To achieve these goals, technical scheme of the present invention is: large-scale pair of trench cross section ring (hereinafter to be referred as ring) radial-axial rolling manufacturing process, comprises following performing step:

(1) base: by bar section from room temperature homogeneous heating to forge hot deformation temperature, then by hot material section on forcing press through jumping-up, punching, punching the wad, make rolling ring blank.Ring blank size is determined as follows

1) calculate ring volume and sectional area

Ring volume be calculated as follows

Wherein, for ring width; , be respectively the inside and outside radius of ring; for ring ditch groove radius; for trench cross section central angle.

Ring sectional area be calculated as follows

, wherein for ring wall thickness.

2) determine rolling ratio

Rolling ratio for ring blank sectional area with ring sectional area ratio, it has reflected ring blank rolling deformation degree, rolling is than larger, ring blank deflection is larger.Rolling is than too little, and ring blank can not produce abundant distortion and obtain grain structure tiny and that be evenly distributed; Rolling is larger than too, and ring blank easily produces the tissue defects such as internal injury, crackle because of excessive deformation.For large-scale pair of groove ring radial-axial rolling, value is generally taken as 2.5~4.

3) determine radial and axial amount of feeding ratio

Ring blank is in the operation of rolling, and its radial thickness and axial height reduce simultaneously, and the reasonable distribution of radial and axial deflection is very important to rolling process stability and shaping ring geometric accuracy.For large-scale pair of groove ring radial-axial rolling, radial and axial amount of feeding ratio can determine by following formula:

Wherein, , be respectively the radial and axial total feed amount of ring rolling, , for ring blank wall thickness and height.

4) determine ring blank wall thickness and height

According to rolling ratio , radial and axial amount of feeding ratio , can determine ring blank wall thickness and height for

5) determine the inside and outside radius of ring blank

According to blank wall thickness , highly with ring volume , in conjunction with plastic deformation constancy of volume principle, can determine ring blank outer radius , inside radius for

(2) rolling groove design: rolling groove is comprised of driven roller working face and core roller working face.Wherein, driven roller working face is the face of cylinder, and core roller working face is combined by the face of cylinder and two ditch spheres, and driven roller and core roll structure are as shown in Figure 4.Driven roller and core roller working face size are determined by following:

1) determine driven roller working face radius and width

In order to guarantee that ring stable rolling is shaped, driven roller linear velocity conventionally get 1.1~1.3m/s, according to driven roller linear velocity can determine driven roller working face radius , wherein, for driven roller rotating speed, for motor speed, for gearratio, , by device parameter, determined.Driven roller face width

2) determine core roller ditch ball size

The core roller ditch ball ring groove that is used for being shaped, its size is corresponding with ring groove dimensions, can determine as follows

Wherein, , be respectively ring gash depth and width, , , , be respectively the core roller ditch ball degree of depth, highly, radius and cross section central angle.

3) determine core roller ditch spherical radius and width

In order to guarantee that ring blank is in radially pass generation continuous rolling distortion, driven roller working face radius and core roller ditch spherical radius should meet following condition.

In formula, for core roller ditch spherical radius; for angle of friction, for coefficient of friction.In order to make core roller can penetrate smoothly ring blank endoporus, be rolled, core roller maximum functional radius surface should guarantee conventionally .According to above-mentioned condition, can determine that core roller ditch spherical radius span is

Thereby can determine that core roller face of cylinder radius is .According to geometrical relationship, can determine that each section of working face axial width of core roller is

(3) roll forming: the ring blank making is put to machine for rolling ring and be rolled, the operation of rolling is controlled by pre-rolling, main rolling, shaping rolling three phases.Pre-rolling sequence, controls core roller and epicone roller difference radially and axially feeding at a slow speed, eliminates gradually and forges Wall-Thickness Difference and the difference in height that base produces; Main rolling sequence, makes full use of capacity of equipment, controls core roller and epicone roller difference radially and axially with very fast feeding, makes ring produce fully distortion; Shaping rolling sequence, outside ring during span predetermined value 100~200mm, controlling core roller and epicone roller distinguishes radially and axially feeding at a slow speed, eliminate Wall-Thickness Difference and ovality that ring distortion produces, keep ring slowly to grow up, when surveyed ring external diameter reaches predetermined value, radial and axial feed-disabling, the operation of rolling finishes.In the operation of rolling, each stage feed speed and the amount of feeding are controlled curve as shown in Figure 5, and in figure, each parameter is determined by following:

Radial feed speed: , ,

Radial feeds: , , ,

Axial feed velocity: , ,

Axial feeding: , , ,

Wherein,

For making ring produce the needed minimum feed speed of rolling deformation, .

The present invention adopts large-scale pair of groove ring of ring radial-axial rolling processes, by total, design ring blank and rolling groove and controlled rolling process, realization is configured as two groove rings by rectangle ring blank Direct Rolling, material and machining period consumption have been reduced, having improved ring metal streamline distributes, improve production efficiency and product quality, reduced production cost.

Accompanying drawing explanation

Fig. 1 is the ring radial-axial rolling schematic diagram of the embodiment of the present invention;

1-driven roller, 2-core roller, 3-guide bars, 4-ring blank, 5-epicone roller, bores roller under 6-, 7-measuring roller;

Fig. 2 is the ring sectional view of the embodiment of the present invention;

Fig. 3 is the ring blank sectional view of the embodiment of the present invention;

Fig. 4 is the driven roller face structure figure of the embodiment of the present invention;

Fig. 5 is the core roller face structure figure of the embodiment of the present invention;

Fig. 6 is ring rolling radial feeds and the radial feed speed control curve figure of the embodiment of the present invention;

1. pre-rolling sequence, 2. main rolling sequence, 3. shaping rolling sequence in figure;

Fig. 7 is that ring rolling axial feeding and the axial feed velocity of the embodiment of the present invention controlled curve map;

1. pre-rolling sequence, 2. main rolling sequence, 3. shaping rolling sequence in figure.

The specific embodiment

The large-scale pair of groove ring (abbreviation ring) as shown in Figure 2 of take is concrete objective for implementation, and ring physical dimension is: outer radius for 1050mm, inside radius be 944, width for 178mm, for 40.25mm, for 18.5mm, groove central angle for , groove arc radius for 20mm, gash depth for 17mm, groove width for 39.5mm.Its radial-axial rolling manufacturing process is realized as follows:

1) base: by bar section from room temperature homogeneous heating to forge hot deformation temperature, then by hot material section on forcing press through jumping-up, punching, punching the wad, make ring blank 4 for rolling.According to ring blank 4 size design methods, get rolling ratio be 3.5, determine that ring blank 4 is of a size of: outer radius for 409.51mm, inside radius for 162.87mm, width for 251.63mm.(shown in Fig. 3).

2) rolling groove design: get roll line speed for 1.2m/s, according to rolling groove method for designing, by the rolling groove of structural design shown in Fig. 4, wherein: driven roller 1 working face radius for 350mm, width for 178mm; The core roller 2 ditch ball degree of depth for 17mm, ditch ball width for 39.5mm, ditch ball central angle for , the ditch radius of a ball for 20mm, core roller 2 ditch spherical radius for 150mm, face of cylinder radius for 133mm, core roller 2 width for 178mm, for 113.88mm, for 18.5mm, for 40.25mm.

3) roll forming: the ring blank making by above-mentioned size 4 is put to machine for rolling ring and be rolled, the operation of rolling is controlled by pre-rolling, main rolling, shaping rolling three phases.Radial and axial feed speed of each stage of the operation of rolling and the amount of feeding are controlled by curve shown in Fig. 6, wherein: pre-rolling sequence, radial and axial feed speed , be respectively 0.65mm/s, 0.38mm/s, the radial and axial amount of feeding , be respectively 6.18mm, 3.68mm; Main rolling sequence, radial and axial feed speed , be respectively 3.78mm/s, 2.24mm/s, the radial and axial amount of feeding , be respectively 105.09mm, 62.59mm; Shaping rolling sequence, radial and axial feed speed , be respectively 0.54mm/s, 0.32mm/s, the radial and axial amount of feeding , be respectively 12.36mm, 7.36mm.When the measuring roller 7 ring external diameter of surveying reaches predetermined value, radial and axial feed-disabling, the operation of rolling finishes.

Claims (1)

1. a large-scale interior pair of groove ring radial-axial rolling manufacturing process, comprises following performing step:
(1) base: by bar section from room temperature homogeneous heating to forge hot deformation temperature, then by hot material section on forcing press through jumping-up, punching, punching the wad, make rolling ring blank, ring blank size is determined as follows
1) calculate ring volume and sectional area
Ring volume is pressed following formula and is determined
Wherein, for ring width; , be respectively the inside and outside radius of ring; for ring ditch groove radius; for trench cross section central angle;
Ring sectional area pressing following formula determines
, wherein for ring wall thickness;
2) determine rolling ratio
Rolling ratio for ring blank sectional area with ring sectional area ratio, rolling ratio value 2.5~4;
3) determine radial and axial amount of feeding ratio
Radial and axial amount of feeding ratio pressing following formula determines:
Wherein, , be respectively the radial and axial total feed amount of ring rolling, , for ring blank wall thickness and height, for ring gash depth;
4) determine ring blank wall thickness and height
According to rolling ratio , radial and axial amount of feeding ratio , determine ring blank wall thickness and height for
5) determine the inside and outside radius of ring blank
According to blank wall thickness , highly with ring volume , in conjunction with plastic deformation constancy of volume principle, determine ring blank outer radius , inside radius for
(2) rolling groove design: rolling groove is comprised of driven roller working face and core roller working face, driven roller working face is the face of cylinder, core roller working face is combined by the face of cylinder and two ditch spheres, and driven roller working face and core roller working face size are determined according to the following steps:
1) determine driven roller working face radius and width
Driven roller linear velocity get 1.1~1.3m/s, according to driven roller linear velocity determine driven roller working face radius , wherein, for driven roller rotating speed, for motor speed, for gearratio, motor speed , gearratio by device parameter, determined driven roller face width
2) determine core roller ditch ball size
The core roller ditch ball ring groove that is used for being shaped, core roller ditch ball size is corresponding with ring groove dimensions, by following formula, determines
Wherein, , be respectively ring gash depth and width, , , , be respectively the core roller ditch ball degree of depth, highly, radius and cross section central angle;
3) determine core roller ditch spherical radius and width
Driven roller working face radius and core roller ditch spherical radius meet following formula
In formula, for core roller ditch spherical radius; for angle of friction, for coefficient of friction, core roller maximum functional radius surface meets , according to above-mentioned condition, determine that core roller ditch spherical radius span is
Thereby determine that core roller face of cylinder radius is , determine that each section of working face axial width of core roller is
Wherein, B 1afor the axial distance of groove in ring to ring upper surface, B 1bfor the axial distance between groove in ring and lower groove;
(3) roll forming: the ring blank making is put to machine for rolling ring and be rolled, the operation of rolling is controlled by pre-rolling, main rolling, shaping rolling three phases; Pre-rolling sequence, controls core roller and epicone roller difference radially and axial feed, pre-rolling radial feed speed , pre-rolling radial feeds , pre-rolling axial feed velocity , pre-rolling axial feeding , eliminate gradually and forge Wall-Thickness Difference and the difference in height that base produces; Main rolling sequence, controls core roller and epicone roller difference radially and axial feed, main rolling radial feed speed , main rolling radial feeds , main rolling axial feed velocity , main rolling axial feeding , make ring produce fully distortion; Shaping rolling sequence, outside ring during span predetermined value 100~200mm, controls core roller and epicone roller respectively radially and axial feed, shaping rolling radial feed speed , shaping rolling radial feeds , shaping rolling axial feed velocity , shaping rolling axial feeding , eliminate Wall-Thickness Difference and ovality that ring distortion produces, keep ring slowly to grow up, when measuring roller is surveyed ring external diameter and is reached predetermined value, radial and axial feed-disabling, the operation of rolling finishes,
Wherein for making ring produce the needed minimum feed speed of rolling deformation, .
CN201110414446.5A 2011-12-13 2011-12-13 Radial and axial rolling forming method for large-sized double-groove ring piece CN102615221B (en)

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JP6350920B2 (en) * 2013-03-21 2018-07-04 日立金属株式会社 Ring rolling material
CN103567336A (en) * 2013-11-22 2014-02-12 重庆大学 Ring rolling mill for rolling production of seamless ring piece with special-shaped cross section
CN105195714B (en) * 2015-09-23 2017-07-25 太原科技大学 A kind of internal layer Q345B outer layers 40Cr is combined ring casting and rolles over manufacturing process
CN105170850B (en) * 2015-09-23 2016-11-09 定州市金华蓝天汽车零部件有限公司 A kind of centrifugal casting bi-metal double is combined ring hot rolling forming technique
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CN105396996A (en) * 2015-12-02 2016-03-16 贵州安大航空锻造有限责任公司 Isotropic rolling method for beta-phase titanium alloy rectangular ring
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