A processing technology for engine tail nozzle forging and its manufacturing die

Abstract

The invention discloses a processing technology for engine tail nozzle forgings and a manufacturing die thereof, which realizes forging and forming processing from cylindrical ring blank to tail nozzle forgings through the process flow of blank inspection, shot peening, chamfering, lubricant application, sheathing, pair binding, blank heating, first-fire die forging, shot peening, lubricant application, sheathing, pair binding, pre-forging heating, die preheating, second-fire die forging, shot peening, final inspection, warehousing, and delivery, wherein the cylindrical ring blank is made into a pre-forging and finally into a tail nozzle forging by a cone hole expansion forming die during first-fire die forging and an upsetting extrusion forming die during second-fire die forging. The processing technology for engine tail nozzle forgings and the manufacturing die thereof make the structure and size of the formed tail nozzle forgings closer to the size of the engine tail nozzle parts, the later machining allowance is small, the difficulty is reduced, the production efficiency is improved, and the production cost is reduced, and the performance of the product is also significantly improved after two forgings.

Description

Technical Field

[0001] The invention relates to the field of engine tail nozzle manufacturing, and in particular to a processing technology for engine tail nozzle forgings and a manufacturing die thereof. Background Art

[0002] The tail nozzle is an important component of an aircraft engine, and its structural precision is required to be high. Since it is the jet exhaust port of the aircraft engine, the tail nozzle also needs to have sufficient high temperature resistance and structural strength.

[0003] Most of the existing aircraft engine tail nozzles are made of high-temperature alloy materials to ensure that they have a small deformation range under high temperature. The existing aircraft engine tail nozzles have a structure similar to a cylindrical structure, with a through hole in the center that connects the front and back. Due to the high precision requirements and large size structure, the processing difficulty is relatively high. The existing engine tail nozzle processing method is generally to first forge a blank material of a specific alloy material into a cylindrical blank with a ring-shaped structure, and then put the cylindrical blank into a lathe for machining, and remove excess material through rough machining, semi-finishing and finishing, and finally form an engine tail nozzle of the required size.

[0004] Although this method can eventually realize the processing of the engine tail nozzle and meet the final size requirements, the difference between the structural size of the cylindrical blank after forging and the final product is relatively large, and the machining requires a large amount of margin to be removed, thus causing a large waste of materials. In addition, the machining requirements and difficulty are higher, the processing time is long, which greatly affects the processing efficiency and increases the production cost. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a processing technology and a manufacturing die for an engine tail nozzle forging which can improve production efficiency and reduce production costs.

[0006] In order to solve the above technical problems, the present invention is implemented by the following technical solutions: a process for processing an engine tail nozzle forging, comprising the following steps:

[0007] A. Billet inspection: The cylindrical ring blank is re-inspected. Its height is 562mm, the outer diameter is 675mm, and the inner diameter of the center hole is 465mm. The cylindrical ring blank is made of GH4169 high-temperature alloy. The main chemical element contents (weight percentage) of the GH4169 high-temperature alloy are: C content ≤0.08%, Cr content 17.0%~21.0%, Ni content 50.0%~55.0%, Co content ≤1.0%, Mo content 2.80%~3.30%, Al content 0.30%~0.70%, Ti content 0.75%~1.15%, Nb content 4.75%~5.50%, B content ≤0.006%, Mg content ≤0.01%, Mn content ≤0.35%, Si content ≤0. .35%, P content ≤0.015%, S content ≤0.015%, Cu content ≤0.30%, Ca content ≤0.01%, Pb content ≤0.0005%, Se content ≤0.0003%, the balance is Fe, to ensure that the material meets the requirements;

[0008] B. Shot peening: clean the surface of the cylindrical ring blank and check whether there are defects on the surface of the cylindrical ring blank. If there are defects, communicate with the customer and make detailed records on the turnover card. After the customer confirms that grinding is required, use an angle grinder to grind it. The width-to-depth ratio is >6 and the transition is smooth;

[0009] C. Chamfer: Chamfer of end face of cylindrical ring blank C20;

[0010] D. Apply lubricant: After cleaning the surface of the cylindrical ring blank, preheat it to about 150°C, then evenly apply lubricant 1-2 times, and the coating must not be damaged after application;

[0011] E. Wrapping and thermocouple binding: Cut the corresponding 25mm thick insulation cotton according to the size. After wrapping the cylindrical ring blank, the upper end face must be facing upwards and the ingot section numbers must be placed in the same order as before wrapping. Before wrapping, the thermocouple must be tied to the side round surface of the upper end face of the cylindrical ring blank to test whether it works normally, and record the thermocouple number and the position of the blank with thermocouple loading into the furnace;

[0012] F. Billet heating and die preheating: Heat the first-fire forging die and cylindrical ring billet according to the process requirements;

[0013] G. One-fire die forging: The press is debugged, the preheated die is installed on the hydraulic press, and the die is closed and aligned to zero position. The upper die is evenly sprayed with graphite emulsion, and the cylindrical ring blank is placed in the center of the die through the clamp and the operator wrapped with insulation cotton, and the cylindrical ring blank is positioned in the die through the center hole of the cylindrical ring blank. At the same time, the hydraulic press sets the pressure, and the cylindrical ring blank is forged into a pre-forged part with the center hole and the upper and lower ends of the outer part expanding outward;

[0014] H. Shot peening: After the pre-forging is removed from the die, clean the surface of the pre-forging and check whether there are defects on the surface of the pre-forging. If there are defects, grind them with an angle grinder, with a width-to-depth ratio of >6 and a smooth transition;

[0015] I. Apply lubricant: After cleaning the surface of the pre-forging, preheat it to about 150℃, then evenly apply lubricant 1-2 times. Do not damage the coating after application;

[0016] J. Wrapping and tying thermocouples: Cut the corresponding 25mm thick insulation cotton according to the size. After the pre-forging is wrapped, the upper end face must be facing upwards, and the ingot section numbers must be placed in the same order as before wrapping. Before wrapping, the thermocouple must be tied to the round side surface of the upper end face of the pre-forging, and tested to see if it works normally, and the thermocouple number and the position of the pre-forging with thermocouples in the furnace should be recorded;

[0017] K. Pre-forging heating and die preheating: Heat the two-fire die forging die and pre-forging according to the process;

[0018] L. Two-fire die forging: The press is debugged, the preheated die is installed on the hydraulic press, and the die is closed and aligned to zero position. The upper die is evenly sprayed with graphite emulsion, and the pre-forged piece is placed in the center of the die from the heating furnace by the operator with the clamp wrapped with insulation cotton, and is positioned in the die through the center hole of the pre-forged piece. At the same time, the hydraulic press sets the pressure and forges the pre-forged piece into a tail nozzle forging piece;

[0019] M. Shot peening: After the tail nozzle forging is removed from the die, the surface is cleaned and the surface of the tail nozzle forging is checked for defects. If there are defects, it needs to be polished with an angle grinder, with a width-to-depth ratio of >6 and a smooth transition;

[0020] N. Final inspection: Check the shape, size and surface quality of the tail nozzle forging.

[0021] Preferably, in step G, after the hydraulic press sets the pressure, the hydraulic press moves downward at full speed during the idle stroke, and after contacting the cylindrical ring blank, the pressing speed is 15 mm / s, until the underpressure is 25 mm.

[0022] Preferably, in step L, after the hydraulic press sets the pressure, the hydraulic press moves downward at full speed during the idle stroke, and after contacting the pre-forged piece, the pressing speed is 15 mm / s until the mold is closed.

[0023] A die for manufacturing an engine tail nozzle forging, comprising a cone hole expanding forming die for forging a cylindrical ring blank into a pre-forging during single-fire die forging and an upsetting extrusion forming die for forging a pre-forging into a tail nozzle forging during double-fire die forging; the cone hole expanding forming die and the upsetting extrusion forming die are both composed of an upper connecting plate, a lower connecting plate, an upper die, a lower die and a lower punch, the top of the upper die is fixedly connected to the bottom of the upper connecting plate, the bottom of the lower die is fixedly connected to the top of the lower connecting plate, the upper die and the lower die are concentric, the centers of the upper die and the lower die are both provided with a die cavity connected up and down, wherein the center of the bottom of the lower die cavity is provided with a lower die connected to the connecting plate at the bottom surface Punch, the side contour of the combined die cavity of the upper die and the lower die after the die is closed is consistent with the shape and size of the outer side contour of the tail nozzle forging; the center of the die cavity of the upper die in the tapered hole expanding forming die is provided with a hole-expanding punch whose top is fixedly connected to the upper connecting plate, and after the upper die and the lower die in the tapered hole expanding forming die are closed, the internal die cavity and the hole-expanding punch and the lower punch form a pre-forging cavity for forging the pre-forging; the center of the die cavity of the upper die in the upsetting forming die is provided with a forming punch whose top is fixedly connected to the upper connecting plate, and after the upper die and the lower die in the upsetting forming die are closed, the internal die cavity and the forming punch and the lower punch form a final forging cavity for forging the tail nozzle forging.

[0024] Preferably, the lower punch is composed of a plug and a push rod having the same shape and size as the center hole at the bottom of the tail nozzle forging. The push rod is fixedly arranged at the bottom center of the plug and is formed as one piece. A withdrawal hole connected up and down is arranged at the center of the lower connecting plate. The push rod is located in the withdrawal hole, and the end of the push rod is connected to the withdrawal machine arranged under the lower connecting plate. The bottom of the plug contacts the top surface of the lower connecting plate.

[0025] Preferably, the outer side surface of the expansion punch has a conical structure.

[0026] Preferably, the bottom of the upper mold is provided with a centering hole that can be sleeved and matched with the outer top of the lower mold.

[0027] Preferably, the upper die, the reaming punch, the forming punch and the upper connecting plate, and the lower die and the lower connecting plate are all detachably connected by bolts.

[0028] Preferably, the outer side surface and the bottom surface of the forming punch are rounded, and the radius R of the rounded corner is 160 mm.

[0029] Preferably, the outer side surface and the top surface of the plug are rounded, and the radius R' of the rounded corner is 120 mm.

[0030] Compared with the prior art, the advantages of the present invention are as follows: the die for manufacturing engine tail nozzle forgings is used to manufacture the cylindrical ring blank of the engine tail nozzle. After the two processes of tapered hole expansion and upsetting, the forging structure and size formed are closer to the size of the engine tail nozzle parts. The later machining allowance is small, the difficulty is reduced, the production efficiency is improved, the material consumption and production cost are reduced, and the performance of the product is also significantly improved after two forgings. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the cross-sectional structure of a cone hole expansion forming die for an engine tail nozzle forging of the present invention;

[0032] Figure 2 It is a schematic diagram of the cross-sectional structure of an engine tail nozzle forging upsetting extrusion die of the present invention;

[0033] Figure 3 It is a schematic diagram of the structure of a forming punch in an upsetting extrusion die for an engine tail nozzle forging of the present invention;

[0034] Figure 4 It is a schematic diagram of the structure of a lower punch in a die for manufacturing an engine tail nozzle forging of the present invention;

[0035] Figure 5 It is a schematic diagram of the top structure of the cylindrical ring blank;

[0036] Figure 6 yes Figure 5 Structural cross-section view of AA in the middle;

[0037] Figure 7 This is a sectional view of the side structure of the engine tail nozzle pre-forging;

[0038] Figure 8 It is a cross-sectional view of the side structure of the engine tail nozzle forging.

[0039] In the figure: 1. cone hole expansion forming die; 2. upsetting extrusion forming die; 3. upper connecting plate; 4. lower connecting plate; 41. withdrawal hole; 5. upper die; 51. centering hole; 6. lower die; 7. lower punch; 71. ejector head; 72. ejector rod; 8. hole expansion punch; 9. pre-forging cavity; 10. forming punch; 11. final forging cavity; 12. cylindrical ring blank; 121. center hole; 13. pre-forging piece; 14. tail nozzle forging piece. DETAILED DESCRIPTION

[0040] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0041] Figure 1 and Figure 2The die for manufacturing an engine tail nozzle forging shown in the figure comprises a cone hole expanding forming die 1 for forging a cylindrical ring blank 12 into a pre-forging 13 during a single-fire die forging, and an upsetting extrusion forming die 2 for forging the pre-forging 13 into a tail nozzle forging 14 during a double-fire die forging; the cone hole expanding forming die 1 and the upsetting extrusion forming die 2 are both composed of an upper connecting plate 3, a lower connecting plate 4, an upper die 5, a lower die 6 and a lower punch 7, the top of the upper die 5 is fixedly connected to the bottom of the upper connecting plate 3, the bottom of the lower die 6 is fixedly connected to the top of the lower connecting plate 4, the upper die 5 and the lower die 6 are concentric, and the centers of the upper die 5 and the lower die 6 are both provided with a die cavity connected to the upper and lower sides, wherein the center of the bottom of the die cavity of the lower die 6 is provided with a lower punch connected to the connecting plate 4 on the bottom surface 7, the side contour of the die cavity of the upper die 5 and the lower die 6 after the die is closed is consistent with the outer side contour shape and size of the tail nozzle forging 14; the center of the die cavity of the upper die 5 in the said cone hole expanding forming die 1 is provided with a hole expanding punch 8 whose top is fixedly connected to the upper connecting plate 3, and after the upper die 5 and the lower die 6 in the said cone hole expanding forming die 1 are closed, the internal die cavity thereof, the hole expanding punch 8 and the lower punch 7 form a pre-forging cavity 9 for forging the pre-forging 13; the center of the die cavity of the upper die 5 in the said upsetting forming die 2 is provided with a forming punch 10 whose top is fixedly connected to the upper connecting plate 3, and after the upper die 5 and the lower die 6 in the said upsetting forming die 2 are closed, the internal die cavity thereof, the forming punch 10 and the lower punch 7 form a final forging cavity 11 for forging the tail nozzle forging 14.

[0042] like Figure 4 As shown, in order to have both the forging function and the material stripping function, the lower punch 7 is composed of a plug 71 and a push rod 72 which are consistent with the shape and size of the bottom center hole of the tail nozzle forging 14. The push rod 72 is fixedly arranged at the bottom center of the plug 71 and is formed as one piece. A material stripping hole 41 which is connected up and down is arranged at the center of the lower connecting plate 4. The push rod 72 is located in the material stripping hole 41, and its end is connected to the material stripping machine arranged below the lower connecting plate 4. The bottom of the plug 71 is in contact with the top surface of the lower connecting plate 4.

[0043] In order to facilitate the expansion of the cylindrical ring blank 12, the outer side surface of the expansion punch 8 is a conical structure.

[0044] In order to facilitate centering of the upper mold 5 and the lower mold 6 and reduce mold manufacturing costs, a centering hole 51 that can be sleeved and matched with the outer top of the lower mold 6 is provided at the bottom of the upper mold 5.

[0045] In order to facilitate the replacement of vulnerable parts in the mold and reduce the use cost, the upper mold 5, the expansion punch 8, the forming punch 10 and the upper connecting plate 3, and the lower mold 6 and the lower connecting plate 4 are all detachably connected by bolts.

[0046] like Figure 3 and Figure 4As shown, in order to facilitate the metal to flow into the die cavity during forging, the outer side and bottom surface of the forming punch 10 are rounded, and the radius R of the rounded corner is 160 mm; the outer side and top surface of the plug 71 are rounded, and the radius R' of the rounded corner is 120 mm.

[0047] In combination with the above-mentioned die, the engine tail nozzle forging processing process specifically includes the following steps:

[0048] A. Blank inspection: Re-inspect the cylindrical ring blank 12, such as Figure 5 and Figure 6 As shown, the cylindrical ring blank 12 has a height of 562 mm, an outer diameter of 675 mm, and an inner diameter of the center hole of 465 mm. The cylindrical ring blank is made of GH4169 high-temperature alloy. The main chemical element contents (weight percentage) of the GH4169 high-temperature alloy are: C content ≤0.08%, Cr content 17.0%~21.0%, Ni content 50.0%~55.0%, Co content ≤1.0%, Mo content 2.80%~3.30%, Al content 0.30%~0.70%, Ti content 0.75%~1.15%, Nb content 4.75%~5.50%, B content ≤0.006%, Mg content ≤0.01%, Mn content ≤0.35%, Si content ≤0.35%, P content ≤0. .015%, S content ≤0.015%, Cu content ≤0.30%, Ca content ≤0.01%, Pb content ≤0.0005%, Se content ≤0.0003%, the balance is Fe, to ensure that the material meets the requirements;

[0049] B. Shot peening: clean the surface of the cylindrical ring blank 12 and check whether there are defects on the surface of the cylindrical ring blank 12. If there are defects, communicate with the customer and make detailed records on the turnover card. After the customer confirms that grinding is required, use an angle grinder to grind it. The width-to-depth ratio is >6 and the transition is smooth;

[0050] C. Chamfer: Chamfer of the end face of the cylindrical ring blank 12 is C20;

[0051] D. Apply lubricant: After cleaning the surface of the cylindrical ring blank 12, preheat it to about 150°C, then evenly apply lubricant 1-2 times, and the coating must not be damaged after application;

[0052] E. Wrapping and tying thermocouples: Cut the corresponding 25mm thick insulation cotton according to the size. After wrapping the cylindrical ring blank 12, the upper end face must be facing upwards and the ingot section numbers must be placed in the same order as before wrapping. Before wrapping, the thermocouple must be tied to the side round surface of the upper end face of the cylindrical ring blank 12 to test whether it works normally, and record the thermocouple number and the position of the blank with thermocouples in the furnace;

[0053] F. Blank heating and die preheating: a fire forging die and a cylindrical ring blank 12 are heated according to the process requirements, wherein the fire forging die is a tapered hole expanding forming die 1;

[0054] G. One-fire die forging: The press is debugged, the preheated tapered hole forming die 1 is installed on the hydraulic press, and the die is closed and aligned to zero position. The upper die 5 is evenly sprayed with graphite emulsion, and the cylindrical ring blank 12 is placed in the center of the tapered hole forming die 1 from the heating furnace by the operator who wraps the insulation cotton with clamps, and is positioned in the tapered hole forming die 1 through the center hole 121 of the cylindrical ring blank 12. At the same time, the hydraulic press is set with pressure, and the hydraulic press moves downward at full speed during the idle stroke. After contacting the cylindrical ring blank, the pressing speed is 15mm / s, and the pressing is performed until the underpressure is 25mm, and the cylindrical ring blank 12 is forged as shown below. Figure 7 The central hole 121 and the pre-forged part 13 with the upper and lower ends expanding outwardly;

[0055] H. Shot peening: After the pre-forged part 13 is removed from the tapered hole forming die 1, its surface is cleaned and checked for defects. If there are defects, it needs to be polished with an angle grinder, with a width-to-depth ratio of >6 and a smooth transition;

[0056] I. Apply lubricant: After cleaning the surface of the pre-forging 13, preheat it to about 150°C, then evenly apply lubricant 1-2 times, and the coating must not be damaged after application;

[0057] J. Wrapping and tying thermocouples: Cut the corresponding 25mm thick insulation cotton according to the size. After wrapping the pre-forged piece 13, the upper end face must face up and the ingot section numbers must be placed in the same order as before wrapping. Before wrapping, the thermocouple must be tied to the round side surface of the upper end face of the pre-forged piece 13, and tested whether it works normally, and the thermocouple number and the furnace loading position of the pre-forged piece 13 with thermocouples must be recorded;

[0058] K. Pre-forging heating and die preheating: heating the two-fire die forging die and the pre-forging 13 according to the process, wherein the two-fire die forging die is an upsetting extrusion die 2;

[0059] L. Two-fire die forging: The press is debugged, the preheated upsetting die 2 is installed on the hydraulic press, and the die is closed and aligned to zero position. The upper die 5 is evenly sprayed with graphite emulsion, and the pre-forged piece 13 is placed from the heating furnace to the inner center of the upsetting die 2 through the clamp and the operator with the insulation cotton wrapped, and the pre-forged piece 13 is positioned in the upsetting die 2 through the center hole 121 of the pre-forged piece 13. At the same time, the hydraulic press is set to the pressure, and the hydraulic press moves downward at full speed during the idle stroke. After contacting the pre-forged piece, the pressing speed is 15mm / s, and the pre-forged piece 13 is forged into the following shape. Figure 8 The tail nozzle forging 14 shown;

[0060] M. Shot peening: After the tail nozzle forging 14 is removed from the upsetting extrusion die 2, the surface is cleaned and the surface of the tail nozzle forging 14 is checked for defects. If there are defects, it needs to be polished with an angle grinder, with a width-to-depth ratio of >6 and a smooth transition;

[0061] N. Final inspection: Check the shape, size and surface quality of the tail nozzle forging 14.

[0062] In step G, the working principle of the tapered hole expanding forming die 1 is as follows: the preheated cylindrical ring blank 12 is placed in the die cavity of the lower die 6, the bottom of the center hole 121 of the cylindrical ring blank 12 is clamped on the outer side of the top of the lower punch 7 at the inner center of the lower die 6, and the centering is achieved. Then, after the hydraulic press sets the pressure, it drives the upper die 5 and the expanding punch 8 connected to the bottom of the upper connecting plate 3 to drive downward. After the head of the expanding punch 8 contacts and enters the center hole 121 of the cylindrical ring blank 12, the expanding punch 8 and the upper die 5 are pressed under the pressure of the hydraulic press. The press will continue to press down. Due to the structural effect of the reaming punch 8 and the lower punch 7, the outer sides of the upper and lower ends of the cylindrical ring blank 12 and the upper and lower ends of the center hole 121 are expanded outward. After the hydraulic press is pressed to an underpressure of 25 mm, the hydraulic press returns and drives the upper die 5 and the reaming punch 8 to reset upward at the same time, so that they are separated from the formed pre-forged part 13. Then, the lower punch 7 is moved upward under the action of the material stripper at the bottom of the lower connecting plate 4, and the pre-forged part 13 at its upper end is ejected. Finally, the pre-forged part 13 can be taken out by a mechanical clamp.

[0063] In the step L, the working principle of the upsetting die 2 is as follows: the preheated pre-forging 13 is placed in the die cavity of the lower die 6, the bottom of the center hole 121 of the pre-forging 13 is clamped on the outer side of the top of the lower punch 7 in the center of the lower die 6, and the centering is achieved, and then the hydraulic press drives the upper die 5 connected to the bottom of the upper connecting plate 3 and the forming punch 10 to drive downward after setting the pressure. After the head of the forming punch 10 contacts and enters the center hole 121 of the pre-forging 13, the forming punch 10 and the upper die 5 will continue to press down under the pressure of the hydraulic press. The contact ends of the punch 7 with the center hole 121 are both rounded ends, which makes it easier for the metal to flow to various parts of the final forging cavity 11. After the hydraulic press drives the upper die 5 and the lower die 6 to close the mold, that is, after the centering hole 51 at the bottom of the upper die 5 is completely sleeved on the upper end of the lower die 6, the hydraulic press returns and drives the upper die 5 and the forming punch 10 to reset upward at the same time, so that they are separated from the formed tail nozzle forging 14. Then, the lower punch 7 moves upward under the action of the material ejector at the bottom of the lower connecting plate 4, and the tail nozzle forging 14 located at its upper end is ejected. Finally, the tail nozzle forging 14 can be taken out by a mechanical clamp.

[0064] This engine tail nozzle forging manufacturing die is used to manufacture the cylindrical ring blank of the engine tail nozzle. After the two processes of tapered hole expansion and upsetting, the forging structure and size formed are closer to the engine tail nozzle part size. The later machining allowance is small, the difficulty is reduced, the production efficiency is improved, the material consumption and production cost are reduced, and the performance of the product is also significantly improved after two forgings.

[0065] It should be emphasized that the above are only preferred embodiments of the present invention and do not limit the present invention in any form. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A process for processing engine tail nozzle forgings, characterized in that: The following steps are involved: A. Billet inspection: The cylindrical ring blank is re-inspected. Its height is 562mm, the outer diameter is 675mm, and the inner diameter of the center hole is 465mm. The cylindrical ring blank is made of GH4169 high-temperature alloy. The main chemical element contents (weight percentage) of the GH4169 high-temperature alloy are: C content ≤0.08%, Cr content 17.0%~21.0%, Ni content 50.0%~55.0%, Co content ≤1.0%, Mo content 2.80%~3.30%, Al content 0.30%~0.70%, Ti content 0.75%~1.15%, Nb content 4.75%~5.50%, B content ≤0.006%, Mg content ≤0.01%, Mn content ≤0.35%, Si content ≤0. .35%, P content ≤0.015%, S content ≤0.015%, Cu content ≤0.30%, Ca content ≤0.01%, Pb content ≤0.0005%, Se content ≤0.0003%, the balance is Fe, to ensure that the material meets the requirements; B. Shot peening: clean the surface of the cylindrical ring blank and check whether there are defects on the surface of the cylindrical ring blank. If there are defects, communicate with the customer and make detailed records on the turnover card. After the customer confirms that grinding is required, use an angle grinder to grind it. The width-to-depth ratio is >6 and the transition is smooth; C. Chamfer: Chamfer of end face of cylindrical ring blank C20; D. Apply lubricant: After cleaning the surface of the cylindrical ring blank, preheat it to about 150°C, then evenly apply lubricant 1-2 times, and the coating must not be damaged after application; E. Wrapping and thermocouple binding: Cut the corresponding 25mm thick insulation cotton according to the size. After wrapping the cylindrical ring blank, the upper end face must be facing upwards and the ingot section numbers must be placed in the same order as before wrapping. Before wrapping, the thermocouple must be tied to the side round surface of the upper end face of the cylindrical ring blank to test whether it works normally, and record the thermocouple number and the position of the blank with thermocouple loading into the furnace; F. Billet heating and die preheating: Heat the first-fire forging die and cylindrical ring billet according to the process requirements; G. One-fire die forging: The press is debugged, the preheated die is installed on the hydraulic press, and the die is closed and aligned to zero position. The upper die is evenly sprayed with graphite emulsion, and the cylindrical ring blank is placed in the center of the die through the clamp and the operator wrapped with insulation cotton, and the cylindrical ring blank is positioned in the die through the center hole of the cylindrical ring blank. At the same time, the hydraulic press sets the pressure, and the cylindrical ring blank is forged into a pre-forged part with the center hole and the upper and lower ends of the outer part expanding outward; H. Shot peening: After the pre-forging is removed from the die, clean the surface of the pre-forging and check whether there are defects on the surface of the pre-forging. If there are defects, grind them with an angle grinder, with a width-to-depth ratio of >6 and a smooth transition; I. Apply lubricant: After cleaning the surface of the pre-forging, preheat it to about 150℃, then evenly apply lubricant 1-2 times. Do not damage the coating after application; J. Wrapping and tying thermocouples: Cut the corresponding 25mm thick insulation cotton according to the size. After the pre-forging is wrapped, the upper end face must be facing upwards, and the ingot section numbers must be placed in the same order as before wrapping. Before wrapping, the thermocouple must be tied to the round side surface of the upper end face of the pre-forging, and tested to see if it works normally, and the thermocouple number and the position of the pre-forging with thermocouples in the furnace should be recorded; K. Pre-forging heating and die preheating: Heat the two-fire die forging die and pre-forging according to the process; L. Two-fire die forging: The press is debugged, the preheated die is installed on the hydraulic press, and the die is closed and aligned to zero position. The upper die is evenly sprayed with graphite emulsion, and the pre-forged piece is placed in the center of the die from the heating furnace by the operator with the clamp wrapped with insulation cotton, and is positioned in the die through the center hole of the pre-forged piece. At the same time, the hydraulic press sets the pressure and forges the pre-forged piece into a tail nozzle forging piece; M. Shot peening: After the tail nozzle forging is removed from the die, the surface is cleaned and the surface of the tail nozzle forging is checked for defects. If there are defects, it needs to be polished with an angle grinder, with a width-to-depth ratio of >6 and a smooth transition; N. Final inspection: Check the shape, size and surface quality of the tail nozzle forging; The first fire forging die is a cone hole expanding forming die (1) used for forging a cylindrical ring blank (12) into a pre-forged piece (13); the second fire forging die is an upsetting forming die (2) used for forging the pre-forged piece (13) into a tail nozzle forged piece (14); the cone hole expanding forming die (1) and the upsetting forming die (2) are both composed of an upper connecting plate (3), a lower connecting plate (4), an upper die (5), a lower die (6) and a lower punch (7); the upper die (5) is fixed at the top The upper die (5) and the lower die (6) are connected to the bottom of the upper connecting plate (3), and the bottom of the lower die (6) is fixedly connected to the top of the lower connecting plate (4). The upper die (5) and the lower die (6) are concentric, and the centers of the upper die (5) and the lower die (6) are both provided with a die cavity connected to the upper and lower centers, wherein the center of the bottom of the die cavity of the lower die (6) is provided with a lower punch (7) whose bottom surface is connected to the connecting plate (4), and the side profile of the combined die cavity of the upper die (5) and the lower die (6) after the die is closed is similar to that of the tail nozzle forging (14). ) have the same outer side profile shape and size; a hole-expanding punch (8) whose top is fixedly connected to the upper connecting plate (3) is arranged at the center of the die cavity of the upper die (5) in the tapered hole expanding forming die (1); the outer side of the hole-expanding punch (8) is in a conical structure; after the upper die (5) and the lower die (6) in the tapered hole expanding forming die (1) are closed, the internal die cavity, the hole-expanding punch (8) and the lower punch (7) form a pre-forging cavity (9) for forging a pre-forged piece (13); A forming punch (10) whose top is fixedly connected to an upper connecting plate (3) is arranged at the center of the die cavity of an upper die (5) in an upsetting extrusion die (2). The outer side surface and the bottom surface of the forming punch (10) are rounded, and the radius R of the rounded corner is 160 mm. After the upper die (5) and the lower die (6) in the upsetting extrusion die (2) are closed, the internal die cavity, the forming punch (10) and the lower punch (7) form a final forging cavity (11) for forging a tail nozzle forging (14).

2. The engine tail nozzle forging processing technology according to claim 1 is characterized in that: In step G, after the hydraulic press sets the pressure, the hydraulic press moves downward at full speed during the idle stroke, and after contacting the cylindrical ring blank, the pressing speed is 15 mm / s, and the pressure is reduced to 25 mm.

3. The engine tail nozzle forging processing technology according to claim 1 is characterized in that: In the step L, after the hydraulic press sets the pressure, the hydraulic press moves downward at full speed during the idle stroke, and after contacting the pre-forged piece, the pressing speed is 15 mm / s until the mold is closed.

4. The engine tail nozzle forging processing technology according to claim 1 is characterized in that: The lower punch (7) is composed of a plug (71) and a push rod (72) having the same shape and size as the bottom center hole of the tail nozzle forging (14); the push rod (72) is fixedly arranged at the bottom center of the plug (71) and is integrally formed; a material withdrawal hole (41) connected up and down is arranged at the center of the lower connecting plate (4); the push rod (72) is located in the material withdrawal hole (41); the end of the push rod (72) is connected to a material withdrawal machine arranged below the lower connecting plate (4); and the bottom of the plug (71) contacts the top surface of the lower connecting plate (4).

5. The engine tail nozzle forging processing technology according to claim 1 is characterized in that: The bottom of the upper die (5) is provided with a centering hole (51) capable of sleeve-fitting with the outer top of the lower die (6).

6. The engine tail nozzle forging processing technology according to claim 1 is characterized in that: The upper die (5), the hole expansion punch (8), the forming punch (10) and the upper connecting plate (3), and the lower die (6) and the lower connecting plate (4) are all detachably connected via bolts.

7. The engine tail nozzle forging processing technology according to claim 4 is characterized in that: The outer side surface and the top surface of the plug (71) are rounded, and the radius R' of the rounded corner is 120 mm.

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