阅读说明：本技术 一种2a70铝合金航空发动机锥形壳体的锻造成形方法 (Forging forming method of 2A70 aluminum alloy aircraft engine conical shell ) 是由 吕正风 宋韦韦 赵国群 韩兆玉 方清万 罗顺成 宋增金 于 2020-05-07 设计创作，主要内容包括：一种2A70铝合金航空发动机锥形壳体的锻造成形方法,包括如下步骤：步骤一：铸锭检验；步骤二：铸锭加热和保温；步骤三：铸锭开坯；步骤四：旋转镦粗；步骤五：分布冲孔；步骤六：内孔加工；步骤七：马架扩孔。本发明的优点是：本发明的锻造成形工艺,可满足该产品的尺寸形状要求,锻件流线完整,变形更加充分,材料利用率明显提高,节约生产成本,且产品性能更优。(A forging forming method of a 2A70 aluminum alloy aircraft engine conical shell comprises the following steps: the method comprises the following steps: inspecting the cast ingot; step two: heating and insulating the cast ingot; step three: casting ingot cogging; step four: rotating and upsetting; step five: distributed punching; step six: processing an inner hole; step seven: and (5) reaming the trestle. The invention has the advantages that: the forging forming process can meet the size and shape requirements of the product, the forging piece is complete in streamline and more sufficient in deformation, the material utilization rate is obviously improved, the production cost is saved, and the product performance is better.)

1. A forging forming method of a 2A70 aluminum alloy aircraft engine conical shell is characterized by comprising the following steps: the method comprises the following steps:

the method comprises the following steps: and (3) ingot casting inspection: checking the surface quality of the cast ingot before heating, and checking whether the surface of the cast ingot has cracks;

step two: heating and heat preservation of cast ingots: placing the cast ingot into an aluminum alloy heating furnace for heating to 460-480 ℃, and preserving heat for 10-13 h; so as to eliminate the defects of dendrite and composition segregation in the cast ingot;

step three: casting ingot cogging: carrying out free forging cogging on the ingot on a free forging hydraulic machine, upsetting the ingot to 73-78% of the height of the ingot, continuously upsetting the ingot to 48-53% of the height of the ingot by turning, rounding and flattening, upsetting for the third time to highly upset the ingot to the diameter of the ingot, stopping upsetting, squaring, drawing, inverting the octagon and rounding until the diameter of the blank reaches the diameter of the ingot, and upsetting the blank again to 60-64% of the height of the ingot to obtain a forged blank;

step four: and (3) rotating and upsetting: placing the forging stock between an upper flat anvil and a lower flat anvil for rotary upsetting, wherein the downward pressing speed of the upper flat anvil is 10mm/s, when the edge of the upper flat anvil deviates from the center of the forging stock by 190-210mm, the rotary upsetting is started, the downward pressing amount of each anvil is 40mm in the spinning process, the lower flat anvil rotates 45 degrees clockwise every time, the upper flat anvil presses 8 times in total when the lower anvil rotates one circle clockwise, the upper flat anvil moves to the center position of the forging stock, upsetting is carried out on the forging stock at the downward pressing speed of 10mm/s, the downward pressing amount is 80mm, the blank is subjected to edge circular rotary upsetting and central position upsetting deformation in sequence until the height of the forging stock is upset to 45-50% of the height of the forging stock obtained in the step two, and a conical forging stock is obtained;

step five: distributed punching: the large end face of the conical forging stock faces upwards, a punch with the diameter of 310mm is used for punching, the size of a working band of the punch is phi 320mm, a bushing is punched, the thickness of a core material is smaller than 80mm, and then a conical punch is used for expanding holes to obtain a conical forging stock with an inner hole;

step six: processing an inner hole: machining the surface of an inner hole of the conical forging stock, and machining and removing the defects on the surface of the inner hole;

step seven: reaming the trestle: and (3) carrying out trestle reaming on the conical forging stock on a free forging hydraulic machine, wherein in the reaming process, the radial wall thickness is continuously reduced, the inner hole is continuously enlarged, the size of the mandrel is changed into a large-diameter mandrel along with the increase of the inner hole, and finally, a final forging piece with the size and the taper meeting the requirements is obtained.

2. The forging forming method for the conical shell of the 2A70 aluminum alloy aircraft engine as claimed in claim 1, wherein the forging forming method comprises the following steps: in the first step, cracks exist on the surface of the cast ingot, and the cast ingot needs to be cleaned, so that the width-depth ratio of the trimmed groove is ensured to be more than 6: 1.

3. The forging forming method for the conical shell of the 2A70 aluminum alloy aircraft engine as claimed in claim 1, wherein the forging forming method comprises the following steps: in the third step of ingot cogging, the cogging temperature is 420-450 ℃, and the finish forging temperature is 350-370 ℃.

4. The forging forming method for the conical shell of the 2A70 aluminum alloy aircraft engine as claimed in claim 1, wherein the forging forming method comprises the following steps: the longitudinal section of the conical forging stock obtained in the fourth step is isosceles trapezoid, and the two base angle angles of the conical forging stock obtained in the fourth step are 78-80 degrees.

5. The forging forming method for the conical shell of the 2A70 aluminum alloy aircraft engine as claimed in claim 1, wherein the forging forming method comprises the following steps: the diameter of the large end of the punch used in the fifth step is 460mm, and the diameter of the small end of the punch used in the fifth step is 320 mm.

6. The forging forming method for the conical shell of the 2A70 aluminum alloy aircraft engine as claimed in claim 1, wherein the forging forming method comprises the following steps: and seventhly, in the broaching operation of the saddle frame, the forging starting temperature is 420 ℃, and the forging finishing temperature is 350 ℃.

Technical Field

The invention belongs to the field of aircraft engine conical shells, and particularly relates to a forging forming method of a 2A70 aluminum alloy aircraft engine conical shell.

Background

The 2A70 alloy aircraft engine shell forging is an important part of an aircraft, the forging is a large thick-wall cylindrical forging with fixed taper, and the forging has large deformation and special shape and has high requirements on a forming process.

Disclosure of Invention

The invention provides a forging forming method of a 2A70 aluminum alloy aircraft engine conical shell, which is used for solving the defects in the prior art.

The invention is realized by the following technical scheme:

a forging forming method of a 2A70 aluminum alloy aircraft engine conical shell comprises the following steps:

the method comprises the following steps: and (3) ingot casting inspection: checking the surface quality of the cast ingot before heating, and checking whether the surface of the cast ingot has cracks;

step two: heating and heat preservation of cast ingots: placing the cast ingot into an aluminum alloy heating furnace for heating to 460-480 ℃, and preserving heat for 10-13 h; so as to eliminate the defects of dendrite and composition segregation in the cast ingot;

step three: casting ingot cogging: carrying out free forging cogging on the ingot on a free forging hydraulic machine, upsetting the ingot to 73-78% of the height of the ingot, continuously upsetting the ingot to 48-53% of the height of the ingot by turning, rounding and flattening, continuously upsetting for the third time, stopping upsetting when the height is upset to the diameter of the ingot, then squaring, drawing out, inverting the octagon and rounding until the diameter of the blank reaches the diameter of the ingot, and upsetting the blank again to 60-64% of the height of the ingot to obtain a forged blank;

step four: and (3) rotating and upsetting: placing the forging stock between an upper flat anvil and a lower flat anvil for rotary upsetting, wherein the lower pressing speed of the upper flat anvil is 10mm/s, when the edge of the upper flat anvil deviates from the center of the forging stock by 190-210mm, the rotary upsetting is started, the pressing amount of each anvil is 40mm in the spinning process, the lower flat anvil rotates 45 degrees clockwise every time, the upper flat anvil presses 8 times in total when the lower flat anvil completes clockwise rotation for one circle, the upper flat anvil moves to the center position of the forging stock, upsetting is carried out on the forging stock at the pressing speed of 10mm/s, the pressing amount is 80mm, the edge of the forging stock is subjected to circular rotary upsetting and the upsetting deformation at the center position in sequence, and the height of the forging stock is upset to 45-50% of the height of the forging stock obtained in the step two, so as to obtain a conical forging stock;

step five: distributed punching: the large end face of the conical forging stock faces upwards, a punch with the diameter of 310mm is used for punching, the size of a working band of the punch is phi 320mm, a bushing is punched, the thickness of a core material is smaller than 80mm, and then a conical punch is used for expanding holes to obtain a conical forging stock with an inner hole;

step six: processing an inner hole: machining the surface of an inner hole of the conical forging stock, and machining and removing the defects on the surface of the inner hole;

step seven: reaming the trestle: and (3) carrying out trestle reaming on the conical forging stock on a free forging hydraulic machine, wherein in the reaming process, the radial wall thickness is continuously reduced, the inner hole is continuously enlarged, the size of the mandrel is changed into a large-diameter mandrel along with the increase of the inner hole, and finally, a final forging piece with the size and the taper meeting the requirements is obtained.

According to the forging forming method of the conical shell of the 2A70 aluminum alloy aircraft engine, cracks exist on the surface of the cast ingot in the first step, the surface needs to be cleaned, and the width-depth ratio of the trimmed groove is ensured to be more than 6: 1.

According to the forging forming method of the conical shell of the 2A70 aluminum alloy aircraft engine, in the step three ingot cogging, the cogging temperature is 420-450 ℃, and the finish forging temperature is 350-370 ℃.

According to the forging forming method of the conical shell of the 2A70 aluminum alloy aircraft engine, the longitudinal section of the conical forging stock obtained in the fourth step is isosceles trapezoid, and two base angle angles of the conical forging stock obtained in the fourth step are 78-80 degrees.

According to the forging forming method of the 2A70 aluminum alloy aircraft engine conical shell, the diameter of the large end of the punch used in the fifth step is 460mm, and the diameter of the small end of the punch used in the fifth step is 320 mm.

In the forging forming method of the conical shell of the 2A70 aluminum alloy aircraft engine, in the seventh step, in the broaching operation of the saddle, the open forging temperature is 420 ℃, and the finish forging temperature is 350 ℃.

The forging forming method of the 2A70 aluminum alloy aircraft engine conical shell is described.

The invention has the advantages that: the forging forming process of the invention does not need to use a forming die with high cost and a machining method to obtain a forging blank with certain taper, can produce a forging piece meeting the size and shape requirements of the product by using a free forging method, has complete flow line of the forging piece, more sufficient deformation and higher material utilization, reduces the turnover process, saves the production cost and has better product performance.

Drawings

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

FIG. 1 is a flow diagram of a process of the present invention;

in FIG. 2, the left diagram is a schematic diagram of edge rotation upsetting, and the right diagram 1 is a schematic diagram of center upsetting;

FIG. 3 is a schematic view of the multi-stage punching process of the present invention;

FIG. 4 is a schematic structural view of the formed forging of the present invention.

Reference numerals: 1. an upper flat anvil; 2. forging a blank; 3. and (5) a lower flat anvil.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.