CN108580764A - A kind of precision form processing technology of aero-engine special alloy casing ring forging - Google Patents

Abstract

The present invention proposes a precision forming process for a special alloy casing ring forging of an aero-engine. The ring is radially rolled by the driving roll of the ring rolling machine and the actively rotating core roll. The process includes the following steps: A. Determine the rolling ratio of the casing ring forging to obtain the size of the preformed ring forging; B. Determine the rolling feed speed and core roll speed according to the required deformation and driving roll speed; C. Rolling is carried out according to the set driving roll speed, rolling feed speed and core roll speed. This method can further reduce the wall thickness of the ring forging and increase the amount of shear deformation on the basis of the accuracy of the existing special alloy casing ring forgings, that is, when the thickness of the casing ring is small, and achieve recrystallization and refinement. The effect of granularity and precision forming can greatly improve the internal structure uniformity and material utilization rate of rolled special alloy casing ring forgings.

Description

A Precision Forming Process for Forgings of Special Alloy Case Rings of Aeroengines

technical field

The invention belongs to the technical field of precision forming processing of special alloy casing ring forgings, and in particular relates to a precision forming processing technology of special alloy casing ring forgings of aero-engines.

Background technique

The casing is the base of the aircraft engine, and is the main structure and main load-bearing part of the entire engine. It has many types, complex shapes, long processing procedures, and difficult manufacturing. It must resist the strong reaction force of the backward high-speed airflow during work. , At the same time, it must bear the impact of high temperature and high-speed airflow for a long time, and the working load is heavy load and transient load. Therefore, the casing must have creep resistance and high-speed impact resistance. The rapidly developing aviation market at home and abroad has a very urgent demand for low-cost, high-reliability receivers.

At present, the production of casings in my country mainly adopts processes such as special alloy upsetting-punching-near-rectangular ring rolling-heat treatment-subsequent machining, and the material utilization rate of rolling casing ring forgings to parts is only 3.3%. A large amount of machining is required in the manufacturing process of the casing, which wastes a lot of materials and significantly increases the material cost and processing cycle; moreover, a large amount of machining destroys the metal flow line and damages the product performance. Develop the precision forming process of the casing, realize the precision ring forging of special alloy casing ring forging, and then greatly improve the performance, reduce the machining allowance, improve the material utilization rate and reduce the manufacturing cost, and become the mass production of special alloy casing in my country to maintain competition the only way to power.

Contents of the invention

The technical problem to be solved by the present invention is to provide a precision forming process for special alloy casing ring forgings of aero-engines in view of the above existing problems. This process greatly improves the internal structure uniformity of rolling special alloy casing ring forgings And material utilization rate, suitable for stable mass production of special alloy casing ring parts with excellent performance and long service life.

The technical solution adopted by the present invention to solve the above-mentioned technical problems is: a precision forming process for a special alloy casing ring forging of an aero-engine, which is characterized in that it includes the following steps:

S1) Determine the rolling ratio of the casing ring forging according to the product size of the casing ring forging, so as to obtain the size of the preformed ring forging;

S2) Determine the rolling feed speed and the core roll speed according to the required deformation amount and the driving roll speed;

S3) Rolling the preformed ring forging according to the set driving roll speed, rolling feed speed and core roll speed to obtain a near-net shape casing ring forging.

According to the above scheme, the step S1) includes the following content:

S11) First, the rolling ratio λ is selected according to the plastic deformation capacity of the material and the degree of precision rolling. For the hot rolling process of special alloys, λ is selected from 1.05 to 1.3;

S12) According to the size of the special alloy casing ring forging, the size of the preformed ring forging is determined by the following formula:

Among them, D, d are the equivalent outer diameter and inner diameter of the casing ring forging, and D ₀ , d ₀ are the equivalent outer diameter and inner diameter of the preformed ring forging.

According to the above scheme, the step S2) includes the following content:

S21) Under the given equipment conditions, the feed per revolution of ring rolling is calculated as follows:

In the formula, Δh _p is the feed rate per revolution, P is the rolling force of the rolling equipment, σ _s is the yield strength of the casing material at the rolling temperature, b is the axial height of the casing ring, D ₁ , D ₂ are the equivalent working outer diameters of the driving roller and the core roller respectively, n is a coefficient, and its value is 3 to 6;

S22) Determine the rolling feed rate according to the size of the preformed ring forging, the feed rate per revolution and the expected deformation:

Wherein, n ₁ is the driving roller speed, and η is the deformation coefficient, which is taken as 1/λ;

S23) according to the rolling feed speed and the driving roll speed, determine the matching core roll rotation speed and calculate as follows:

Among them, t is the rolling time variable, ξ is the speed coefficient, and the value range is 0.1～0.3.

The beneficial effect of the present invention is: to propose a precision forming process for the special alloy case ring forging of an aero-engine. Under the combined action of the driving roller torque and the core roller torque, the part rotates continuously and produces plastic deformation. The inner and outer surfaces of the ring are respectively affected by the torque of the core roller and the torque of the driving roller, and the inner and outer surfaces of the ring are subjected to opposite forces. 1. The deformation zone is "elongated and sheared", which can further reduce the wall thickness of the ring forging and increase the shear on the basis of the accuracy of the existing special alloy casing ring forging, that is, when the thickness of the casing ring is small The amount of deformation can be reduced to achieve the effect of recrystallization, grain refinement and precision forming, thereby greatly improving the internal structure uniformity and material utilization rate of the rolled special alloy casing ring forging, (the material utilization rate of the standard casing parts is reduced from 3.3% to over 5%). It is suitable for stable mass production of special alloy casing ring parts with excellent performance and long service life.

Description of drawings

Fig. 1 is a schematic rolling diagram of a casing ring forging according to an embodiment of the present invention.

Fig. 2 is a schematic structural view of a preformed ring forging according to an embodiment of the present invention.

Fig. 3 is a schematic structural view of a casing ring forging according to an embodiment of the present invention.

Among them: 1. Driving roller, 2. Core roller, 3. Guide roller, 4. Preformed ring forging, 5. Case ring forging

Detailed ways

In order to better understand the present invention, the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

As shown in Figure 1-3, it is a precision forming process for special alloy casing ring forgings of aero-engines. This process mainly uses the driving roll 1, guide roll 3 and actively rotating core roll 2 of the ring rolling machine to carry out the ring forming process. Radial rolling, the process includes the following steps: A. Determine the rolling ratio of the casing ring forging according to the product size of the casing ring forging, so as to obtain the size of the preformed ring forging 4; B. According to the required deformation and drive Roll speed, determine rolling feed speed and core roll speed; C. According to the set drive roll speed, rolling feed speed and core roll speed, roll the pre-formed ring forging to obtain a near-net shape casing Ring forgings 5.

The calculation method for the size of the preformed ring forging is:

A. First, select the rolling ratio λ according to the plastic deformation ability and precision rolling degree of the material. For special alloy hot rolling processing, λ can generally be selected as 1.05-1.3;

B. According to the size of the special alloy casing ring forging, the size of the pre-formed ring forging is determined by the following formula,

In the formula, D, d are the equivalent outer diameter and inner diameter of the casing ring forging, and D ₀ , d ₀ are the equivalent outer diameter and inner diameter of the preformed ring forging.

The calculation method for determining the rotating speed of the core roll is as follows:

A. Under the given equipment conditions, the feed per revolution of ring rolling is calculated as follows,

In the formula, Δh _p is the feed rate per revolution, P is the rolling force of the rolling equipment, σ _s is the yield strength of the casing material at the rolling temperature, b is the axial height of the ring, D ₁ and D ₂ are respectively is the equivalent working outer diameter of the drive roller and the core roller, n is a coefficient, and its value is 3-6;

B. Determine the rolling feed rate according to the size of the preformed ring forging, the feed rate per revolution and the expected deformation,

In the formula, n1 is the rotating speed _of the driving roller, and η is the deformation coefficient, which is generally 1/λ;

C. According to the rolling feed speed and the speed of the driving roll, the calculation of the matching core roll rotation speed is as follows,

In the formula, t is the rolling time variable, and ξ is the speed coefficient, which is taken as 0.2 here.

Preformed ring forgings can be obtained by traditional rolling process, and the general accuracy is about 2%. On this basis, traditional forming process is also used, either insufficient deformation causes insufficient recrystallization to affect the strength of subsequent heat treatment, or maintains the existing thermal deformation state Direct subsequent heat treatment results in low material utilization. Through the above process, even when the wall thickness of the ring forging is already small, a large amount of deformation can still be produced to promote recrystallization and refine grains, and achieve a dimensional accuracy of more than 3‰ for the ring forging, increasing the material utilization rate by more than 30%. , to achieve the effect of 5% of the total utilization rate of casing parts materials.

In summary, this method is suitable for the stable mass production of special alloy casing ring forgings with excellent performance and long service life.

It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should belong to the protection scope of the appended claims of the present invention.

Claims (3)

1. A precision forming process of an aero-engine special alloy casing ring forging, characterized in that it comprises the steps: S1) Determine the rolling ratio of the casing ring forging according to the product size of the casing ring forging, so as to obtain the size of the preformed ring forging; S2) Determine the rolling feed speed and the core roll speed according to the required deformation amount and the driving roll speed; S3) Rolling the preformed ring forging according to the set driving roll speed, rolling feed speed and core roll speed to obtain a near-net shape casing ring forging. 2. The precision forming process of a special alloy casing ring forging of an aero-engine according to claim 1, wherein the step S1) includes the following contents: S11) First, the rolling ratio λ is selected according to the plastic deformation capacity of the material and the degree of precision rolling. For the hot rolling process of special alloys, λ is selected from 1.05 to 1.3; S12) According to the size of the special alloy casing ring forging, the size of the preformed ring forging is determined by the following formula: Among them, D, d are the equivalent outer diameter and inner diameter of the casing ring forging, and D ₀ , d ₀ are the equivalent outer diameter and inner diameter of the preformed ring forging. 3. The precision forming process of a special alloy casing ring forging of an aero-engine according to claim 2, wherein the step S2) includes the following contents: S21) Under the given equipment conditions, the feed per revolution of ring rolling is calculated as follows: In the formula, Δh _p is the feed rate per revolution, P is the rolling force of the rolling equipment, σ _s is the yield strength of the casing material at the rolling temperature, b is the axial height of the casing ring, D ₁ , D ₂ are the equivalent working outer diameters of the driving roller and the core roller respectively, n is a coefficient, and its value is 3 to 6; S22) Determine the rolling feed rate according to the size of the preformed ring forging, the feed rate per revolution and the expected deformation: Wherein, n ₁ is the driving roller speed, and η is the deformation coefficient, which is taken as 1/λ; S23) according to the rolling feed speed and the driving roll speed, determine the matching core roll rotation speed and calculate as follows: Among them, t is the rolling time variable, ξ is the speed coefficient, and the value range is 0.1～0.3.