Straightening process for rod part of titanium alloy valve blank

Abstract

The invention belongs to the technical field of engine valve manufacturing, and particularly relates to a titanium alloy valve blank rod part straightening process which sequentially comprises solution treatment, shot blasting treatment, straightening treatment, aging treatment, secondary straightening treatment and straightening stress elimination. According to the process, rod part straightening and disc part correction are achieved through the double-roller straightening machine, the straightness of the rod part and the back angle jumping sorting qualification rate of the disc part are greatly improved after correction, the overall straightening qualification rate is about 83%, the manufacturing cost is reduced, the production efficiency is improved, and the crack occurrence probability is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of engine valve manufacturing, and provides a titanium alloy valve blank stem straightening process which can improve straightening efficiency and reduce manufacturing cost. Background Art

[0002] During the engine processing, the titanium alloy valve blank needs to be straightened. Due to the material, the current straightening is basically done manually, which has low straightening efficiency and high manufacturing costs.

[0003] The existing manual straightening is that workers use tools to directly knock and straighten the titanium alloy valve blank to eliminate the straightening stress. The finished product size accuracy consistency rate is low, the straightening pass rate is about 47%, the straightening efficiency is low, and the crack tendency is serious, resulting in high labor costs, which also makes the manufacturing cost high, the quality is unstable, and the processing is uncontrolled. Summary of the invention

[0004] In view of this, an object of the present invention is to provide a titanium alloy valve blank stem straightening process which improves straightening efficiency and reduces manufacturing cost.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] The present invention provides a titanium alloy valve blank stem straightening process, which includes the following steps:

[0007] The first step is solution treatment.

[0008] The forged titanium alloy valve blank is solid-solution treated;

[0009] The second step is shot blasting.

[0010] The titanium alloy valve blank processed in the first step is transferred to a shot blasting machine for shot blasting;

[0011] The third step is straightening.

[0012] The titanium alloy valve blank after the shot blasting treatment in the second step is transferred to a double-roller straightening machine for rod straightening and disc correction;

[0013] The fourth step is time-limit processing.

[0014] Aging the titanium alloy valve blank after the straightening treatment in the third step;

[0015] Step 5: Secondary straightening treatment.

[0016] The titanium alloy valve blank after the fourth step is transferred to a double-roller straightening machine for secondary rod straightening and disc correction;

[0017] The sixth step is to eliminate the straightening stress.

[0018] The titanium alloy valve blank processed in the fifth step is passed through a mesh belt furnace to eliminate straightening stress.

[0019] In order to ensure the surface accuracy of the titanium alloy valve blank, in the above scheme, further: in the shot blasting process, the surface of the titanium alloy valve blank is metallic silver-white and is free of oxide scale before the shot blasting is completed.

[0020] To ensure the accuracy of shot blasting, in the above scheme, further: in the shot blasting process, the current used during shot blasting is 21A, and the shot blasting time is 240S.

[0021] In order to ensure the straightness and back angle runout accuracy of the titanium alloy valve blank, in the above scheme, further: the process parameters of the straightening treatment and the secondary straightening treatment are the same.

[0022] In order to ensure the straightening accuracy of the titanium alloy valve blank, in the above scheme, further: in the straightening process step, the pressure of the straightening machine is 3.3MPa and the feed rate is 1mm / S.

[0023] The beneficial effect of the present invention is that: through the above scheme, shot blasting is added before straightening, so that the titanium alloy valve blank can be straightened on the rod and corrected on the disc in a double-roll straightening machine, which effectively improves the straightening efficiency and reduces the manufacturing cost.

[0024] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. DETAILED DESCRIPTION

[0025] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0026] The titanium alloy valve blank stem straightening process of the present invention comprises the following steps:

[0027] The first step is solution treatment.

[0028] The forged titanium alloy valve blank is solid-solution treated;

[0029] The second step is shot blasting.

[0030] The titanium alloy valve blank processed in the first step is transferred to a shot blasting machine for shot blasting;

[0031] The third step is straightening.

[0032] The titanium alloy valve blank after the shot blasting treatment in the second step is transferred to a double-roller straightening machine for rod straightening and disc correction;

[0033] The fourth step is time-limit processing.

[0034] Aging the titanium alloy valve blank after the straightening treatment in the third step;

[0035] Step 5: Secondary straightening treatment.

[0036] The titanium alloy valve blank after the fourth step is transferred to a double-roller straightening machine for secondary rod straightening and disc correction;

[0037] The sixth step is to eliminate the straightening stress.

[0038] The titanium alloy valve blank processed in the fifth step is passed through a mesh belt furnace to eliminate the straightening stress. In this embodiment, due to the setting of the shot blasting process, the titanium alloy valve blank can be directly straightened by a straightening machine, and no longer needs to be directly straightened by manual hammering with tools, which effectively improves the straightening efficiency and reduces the manufacturing cost, and the titanium alloy valve blank straightened by the straightening machine has a high dimensional accuracy consistency rate.

[0039] In order to ensure the surface accuracy of the titanium alloy valve blank, in the above embodiment, further: in the shot blasting process, the surface of the titanium alloy valve blank is metallic silver-white and has no oxide scale before the shot blasting is completed. In this embodiment, the current used during shot blasting is 21A and the shot blasting time is 240S.

[0040] In order to ensure the straightness and back angle runout accuracy of the titanium alloy valve blank, in the above embodiment, further: the process parameters of the straightening process and the secondary straightening process are the same. In this embodiment, in the straightening process and the secondary straightening process, the pressure of the straightening machine is 3.3MPa and the feed rate is 1mm / S.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. A titanium alloy valve blank stem straightening process, characterized in that: The process includes the following steps: The first step is solution treatment. The forged titanium alloy valve blank is solid-solution treated; The second step is shot blasting. The titanium alloy valve blank processed in the first step is transferred to a shot blasting machine for shot blasting; The third step is straightening. The titanium alloy valve blank after the shot blasting treatment in the second step is transferred to a double-roller straightening machine for rod straightening and disc correction; The fourth step is time-limit processing. Aging the titanium alloy valve blank after the straightening treatment in the third step; Step 5: Secondary straightening treatment. The titanium alloy valve blank after the fourth step is transferred to a double-roller straightening machine for secondary rod straightening and disc correction; The sixth step is to eliminate the straightening stress. The titanium alloy valve blank processed in the fifth step is passed through a mesh belt furnace to eliminate straightening stress.

2. The titanium alloy valve blank stem straightening process according to claim 1, characterized in that: In the shot blasting process, the surface of the titanium alloy valve blank is metallic silver-white and has no oxide scale, and the shot blasting is completed.

3. The titanium alloy valve blank stem straightening process according to claim 1 or 2, characterized in that: In the shot blasting process, the current used during shot blasting is 21A and the shot blasting time is 240S.

4. The titanium alloy valve blank stem straightening process according to claim 1, characterized in that: The process parameters of the straightening treatment and the secondary straightening treatment are the same.

5. The titanium alloy valve blank stem straightening process according to claim 1 or 4, characterized in that: In the straightening process and the secondary straightening process, the pressure of the straightening machine is 3.3 MPa and the feed rate is 1 mm / S.