阅读说明：本技术 一种用于截止阀f12台阶轴的制备工艺 (Preparation process for stop valve F12 step shaft ) 是由 孙子城 孙敏 段晓辉 于 2019-10-23 设计创作，主要内容包括：本发明公开了一种用于截止阀F<Sub>12</Sub>台阶轴的制备工艺,属于台阶轴的制备工艺技术领域,通过墩拔成接近于成平的台阶轴毛坯,通过钢模将大直径端与小直径端分开锻造成成品,使得大直径端有约64％的变形量,小直径端有约69％的变形量,这样也保证了大直径端与小直径端有较接近的变形量,从而缩小了因变形量差异较大而引起的性能差异；通过将原铸锭墩拔拉长,再依次将大直径端和小直径端分别进行墩拔锻造成型,节省了材料,提高了加工效率；对每次墩拔后进行严格的保温处理,最大程度的减少因墩拔造成的力学性能的改变,提高产品质量和成品率。(The invention discloses a stop valve F 12 A preparation process of a step shaft belongs to the technical field of preparation processes of step shafts, a step shaft blank which is close to flat is drawn through a pier, a large-diameter end and a small-diameter end are separately forged into a finished product through a steel die, so that the large-diameter end has deformation of about 64 percent, the small-diameter end has deformation of about 69 percent, and the large-diameter end and the small-diameter end have deformation which is close to each other, so that performance difference caused by larger difference of deformation is reduced; the original ingot is drawn and elongated, and then the large-diameter end and the small-diameter end are respectively drawn and forged to form, so that materials are saved, and the processing efficiency is improved; and strict heat preservation treatment is carried out after each pier pulling, so that the change of mechanical properties caused by pier pulling is reduced to the greatest extent, and the product quality and the yield are improved.)

1. A preparation technology for a step shaft of a stop valve F12 is characterized in that: the method comprises the following steps:

s1, first upsetting deformation

Will be provided with

s2, secondary upsetting deformation

Heating the primary intermediate material to 850-870 ℃, then preserving heat for 300-350 min, and performing two-pier two-drawing deformation by using a 3500-4000T oil press to obtain the high-strength high

s3, preparing step shaft blank

Heating the secondary intermediate material to 850-870 ℃, preserving heat for 150-200 min, and hammering the secondary intermediate material into a large-diameter end by 1000-1200 kg of air

s4, preparing a semi-finished step shaft

Inserting the small-diameter end of the step shaft blank into a steel die (1) to enable the inner end face of the large-diameter end of the step shaft to be in contact with the outer end face of the steel die (1), and forging the large-diameter end of the step shaft blank by using a 1000-1200 kg air hammer to obtain a large-diameter end

s5, preparing the finished step shaft

Will be half intoHeating the step shaft to 850-870 ℃, then preserving heat for 120-150 min, and then drawing out the small-diameter end of the semi-finished product to

2. The preparation process for the stepped shaft of the stop valve F12 according to claim 1, wherein: in S1, the first-time pier-drawing deformation amount is 35-40%; the second-time upsetting deformation amount is 40-45%; the third pier-drawing deformation amount is 40-45%; the finish forging temperature is as follows: the skin temperature of the first intermediate material is not lower than 500 ℃.

3. The preparation process for the stepped shaft of the stop valve F12 according to claim 2, wherein: in S2, the first-time upsetting deformation amount is 40-45%; the second-time upsetting deformation amount is 40-50%; the terminal temperature is: the skin temperature of the intermediate material for the second time is not lower than 500 ℃.

4. The preparation process for the stepped shaft of the stop valve F12 according to claim 3, wherein: in S4, the inner diameter of the inner hole of the steel die (1) is the same as the diameter of the small-diameter end of the step shaft blank, and the length of the inner hole of the steel die (1) is the same as the length of the small-diameter end of the step shaft blank.

5. The preparation process for the stepped shaft of the stop valve F12 according to claim 4, wherein: in steps S1 and S2, the hydraulic pressure is 3500T.

6. The preparation process for the stepped shaft of the stop valve F12 according to claim 5, wherein: in steps S3 and S4, the mass of the air hammer is 1000 kg.

Technical Field

The invention relates to the technical field of a preparation process of a step shaft, in particular to a stop valve F₁₂A preparation process of the step shaft.

Background

In the field of mechanical technology, a step shaft is one of the more commonly used parts in a machine, because the size difference of inner holes of standard parts assembled on the same step shaft is large, the step shaft is required to be manufactured to be matched with the standard parts for installation, and the inner diameters of some standard parts are small and the widths of some standard parts are large, so that the diameter of the part matched with the step shaft is small, the length of the part is long, and certain processing difficulty is caused for manufacturing. For F12 step shaft mechanical and chemical properties meeting the ASTM/B381 standard, the minimum values of the mechanical main properties are 483MPa of tensile strength, 345MPa of yield strength, 18 percent of elongation and 25 percent of reduction of area in sequence; the chemical main components Fe and O are 0.30 percent and 0.25 percent respectively in maximum. The existing processing modes comprise two types: the first method is to perform upsetting elongation on ingot blanks, perform circle throwing to prepare large-size bars, and then perform machining forming, and the method has the defects of large raw material waste and long machining time; the second method is to pull and elongate the ingot by pier, throw the round to make large-size bar, then pull and elongate one end, throw the round to make small-diameter bar, cut off the surplus part, the disadvantage of this method is that the part cut off can be reused, but increased the forging cost, and the large diameter end and small diameter end deform the difference greatly, cause the two ends mechanical property to have obvious difference.

Disclosure of Invention

Aiming at the problems, the invention aims to provide a preparation process for a stop valve F12 step shaft, which comprises the steps of drawing and lengthening a cast ingot, forging to form a step shaft blank similar to the appearance of a finished step shaft, forging and forming a large-diameter end through a steel die, and drawing and forming a small-diameter end, so that a large amount of raw materials are saved, mechanical processing is not needed, the manufacturing time is saved, and the production efficiency is improved.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows: a preparation technology for a step shaft of a stop valve F12 is characterized in that: the method comprises the following steps:

s1, first upsetting deformation

Will be provided with

Heating the ingot with the specification to 1030-1080 ℃, preserving heat for 360-400 min, and performing three-pier three-drawing deformation by using a 3500-4000T oil press to obtain the alloyA first intermediate material of a specification;

s2, secondary upsetting deformation

Heating the primary intermediate material to 850-870 ℃, then preserving heat for 300-350 min, and performing two-pier two-drawing deformation by using a 3500-4000T oil press to obtain the high-strength high

A second intermediate material of the specification;

s3, preparing step shaft blank

Heating the secondary intermediate material to 850-870 ℃, preserving heat for 150-200 min, and hammering the secondary intermediate material into a large-diameter end by 1000-1200 kg of air

And the small diameter end isStep shaft blank with specification;

s4, preparing a semi-finished step shaft

Inserting the small-diameter end of the step shaft blank into a steel die (1) to enable the inner end face of the large-diameter end of the step shaft to be in contact with the outer end face of the steel die (1), and forging the large-diameter end of the step shaft blank by using a 1000-1200 kg air hammer to obtain a large-diameter end

And the small diameter end is

A specification semi-finished step shaft;

s5, preparing the finished step shaft

Heating the semi-finished step shaft to 850-870 ℃, preserving heat for 120-150 min, and then drawing out the small-diameter end of the semi-finished product to

And (3) keeping the temperature for 90-120 min at 830-850 ℃ to obtain the finished step shaft.

Preferably, in S1, the first-time upsetting deformation amount is 35 to 40 percent; the second-time upsetting deformation amount is 40-45%; the third pier-drawing deformation amount is 40-45%; the finish forging temperature is as follows: the skin temperature of the first intermediate material is not lower than 500 ℃.

Preferably, in S2, the first-time upsetting deformation amount is 40% -45%; the second-time upsetting deformation amount is 40-50%; the terminal temperature is: the skin temperature of the intermediate material for the second time is not lower than 500 ℃.

Preferably, in S4, the inner diameter of the steel mold inner bore is the same as the diameter of the small-diameter end of the step shaft blank, and the length of the steel mold inner bore is the same as the length of the small-diameter end of the step shaft blank.

Preferably, the hydraulic pressure is 3500T in both step S1 and step S2.

Preferably, in step S3 and step S4, the mass of the air hammer is 1000 kg.

The invention has the beneficial effects that: (1) the preparation method reduces the difference of the mechanical properties of the large-diameter end and the small-diameter end of the step shaft (the large-diameter end has about 64% of deformation and the small-diameter end has no deformation in S4, and the small-diameter end has about 69% of deformation and the large-diameter end has no deformation in S5), thereby ensuring that the large-diameter end and the small-diameter end have closer deformation and reducing the difference of the properties caused by larger difference of the deformations. (2) The original ingot is elongated by upsetting, and the large-diameter end and the small-diameter end are respectively forged and formed by upsetting in sequence, so that materials are saved, and the processing efficiency is improved. (3) And strict heat preservation treatment is carried out after each pier pulling, so that the change of mechanical properties caused by pier pulling is reduced to the greatest extent, and the product quality and the yield are improved.

Drawings

FIG. 1 is a flow chart of the preparation process of the present invention.

Detailed Description

In order to make those skilled in the art better understand the technical solution of the present invention, the following further describes the technical solution of the present invention with reference to the drawings and the embodiments.