Liquid rocket engine branch pipe die forging state milling standard process equipment
By utilizing the automatic centering and positioning of the machining center and the design of aluminum pads in the milling reference process equipment for liquid rocket engine branch pipes, the problems of difficult alignment and insufficient accuracy in traditional machining methods have been solved, achieving efficient and accurate branch pipe machining and reducing the scrap rate.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- XIAN SPACE ENGINE CO LTD
- Filing Date
- 2023-12-28
- Publication Date
- 2026-05-01
AI Technical Summary
Traditional machining methods for liquid rocket engine branch pipes suffer from problems such as difficulty in turning and alignment, uneven machining of the outer circle due to the swing of the overhang section, easy dimensional deviation, poor coaxiality at both ends, and large deviation of the machining reference surface, resulting in low machining efficiency and high scrap rate.
A dedicated milling reference tool is used for branch pipe machining. The machining center automatically centers and positions the end faces of the long and short shafts, and mills out the positioning surface as the reference for subsequent turning machining. Combined with the four-jaw clamping design of the upper end of the branch pipe and the aluminum pad, the positioning accuracy and stability are ensured.
It improved the processing efficiency of branch pipes, reduced the product scrap rate, improved processing accuracy and surface quality, and increased the alignment speed from 4H/piece to 0.5H/piece.
Smart Images
Figure CN121945859A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of machining equipment for liquid rocket engine branch tube forgings, and in particular to a machining equipment for milling references for liquid rocket engine branch tube forgings. Background Technology
[0002] The liquid rocket engine branch pipe is a crucial component connecting the engine generator and valves, serving as a load-bearing intermediate structure. Due to its harsh operating environment, the quality requirements for the product are extremely high. To save on processing costs, the product blank has always been a die forging, with the final dimensions ensured by machining the profile. The traditional processing method involves first clamping the long or short shaft end of the branch pipe on a CNC lathe using a three-jaw chuck, then turning the outer diameter and end face dimensions of the long and short shafts to provide a positioning reference surface for subsequent machining processes. The profile is then machined by milling. The main problems with this method are as follows:
[0003] (1) When turning, three-jaw clamping is used, which makes alignment difficult. In addition, due to the long overhang of the part, the swing of the overhang section during machining causes uneven force on the outer circle, making the dimensions prone to exceed the tolerance and the coaxiality of the two ends poor.
[0004] (2) Traditional processing methods do not take into account the deviation between the machining reference surface and the forging reference surface, which can easily lead to problems such as out-of-tolerance product dimensions and high scrap rate after machining.
[0005] In summary, the large batch size of this part and the low annual processing efficiency and high scrap rate have become bottlenecks restricting product output, which urgently need to be addressed. Summary of the Invention
[0006] This application overcomes the shortcomings of traditional machining methods by providing a convenient and practical tooling for milling the datum of branch pipes, specifically designed for milling the branch pipes on a machining center to create a machining datum. Traditional machining methods use a four-jaw clamp to hold the upper end of the branch pipe (the short shaft), evenly aligning and turning the long shaft end; then, the tooling is reversed and used a three-jaw clamp to hold the already machined outer diameter for machining the short shaft. Due to the considerable distance between the long and short shafts of the branch pipe, and the small size of the short shaft nozzle, the effective clamping area is small, affecting clamping accuracy. Therefore, directly using a lathe for clamping and alignment is difficult and prone to accuracy deviations. This new tooling, after being tightly fitted to the product's outer surface, automatically centers and positions itself on the end faces of the long and short shafts, machining center holes and milling out locating surfaces as positioning datums for subsequent turning and milling. Subsequent turning machining uses two center holes for positioning, effectively solving problems such as difficult turning alignment, uneven outer diameters of the two shafts, and large datum deviations between machined and forged parts. This improves the machining efficiency of branch pipes and reduces product scrap rates.
[0007] Firstly, a process equipment for milling the reference of a liquid rocket engine branch pipe forging is provided, including a main body, a cover plate, and a pad. The main body is a turntable structure with a central shaft on one side, which is connected to the central hole of the turntable chuck for positioning and tool rotation, and is connected to the worktable surface by bolts. A curved groove is machined on the other side to support and position the part and determine the reference coordinates of the part. The cover plate mates with the fixed mounting surface on the main body and is connected to the main body by bolts. The pad is placed between the cover plate and the part. The upper surface of the part or the pad is pressed by bolts through the cover plate, so that the lower surface of the part is in close contact with the curved groove of the main body.
[0008] In conjunction with the first aspect, in some implementations of the first aspect, the main body is symmetrical on both sides, the angle of the curved groove is the same as the angle formed by the nozzles on both sides of the branch pipe, and there are circular slots on both sides, which are the same as the outer diameter of the nozzles on both sides of the branch pipe, in order to fix the outer surface of the branch pipe.
[0009] In conjunction with the first aspect, in some implementations of the first aspect, the part is placed in the curved groove of the main body, and the curved grooves on the side and bottom of the main body are used to fit the outer surface of the part, clamping it tightly, and preventing the clamping force from deforming the part while fixing the product.
[0010] In conjunction with the first aspect, in some implementations of the first aspect, the cover plate includes two first cover plate portions connected to the main body and a second cover plate portion for pressing the parts; the two first cover plate portions are located on both sides of the second cover plate portion, forming a "V" structure of the cover plate together with the second cover plate portion.
[0011] In conjunction with the first aspect, in some implementations of the first aspect, the second cover portion is higher than the first cover portion, and the second cover portion has a cavity for accommodating parts and pads.
[0012] In conjunction with the first aspect, in some implementations of the first aspect, the pad includes a main body and a protruding part to form an L-shaped structure; the main body and the part cooperate, the protruding part protrudes from the main body away from the part, and the protruding part fastens to the end face of the cover plate to realize the installation and positioning of the pad.
[0013] In conjunction with the first aspect, in some implementations of the first aspect, the main body portion of the pad is arc-shaped on the side closest to the part.
[0014] In conjunction with the first aspect, in some implementations of the first aspect, the pad is an aluminum pad.
[0015] In conjunction with the first aspect, in some implementations of the first aspect, the main body is made of a single bar stock, with an outer diameter runout of no more than 0.01 mm and a parallelism requirement of no more than 0.03 mm between the surfaces of the main body.
[0016] In combination with the first aspect, in some implementations of the first aspect, the curved surface groove of the main body provides a concave cavity positioning with an angle of 113° and a radius of R14.7 for the protruding side of the part.
[0017] Compared with the prior art, the solution provided by this application at least includes the following beneficial technical effects:
[0018] (1) The main body is machined from a whole bar. The outer circle runout is not more than 0.01, and the parallelism requirement between each surface of the main bodies is not more than 0.03 mm. It has good rigidity and high positioning accuracy. When ensuring reliable clamping, the part profile and weight-reducing grooves are designed to minimize the weight of the fixture.
[0019] (2) The positioning surface on the main body is designed with an arc-shaped cavity structure, which perfectly fits the profile of the branch pipe forging. While ensuring that the strength of the fixture meets the requirements, it reasonably avoids the problem of unstable part positioning, achieves the purpose of weight reduction, effectively reduces the alignment time, and realizes the rapid positioning and clamping of the workpiece.
[0020] (3) The structure of the aluminum pad is reasonably designed, and the "L"-shaped detachable pad is adopted, as shown in Figure 10 , and an arc on the other side of the part is designed on the outer shape, which can reach a state of fitting with the part and avoid damaging the part when fastening.
[0021] (4) The structure of the cover plate is reasonably designed, and the inverted "U" shape is adopted, as shown in Figure 6 . It does not interfere with the nozzles protruding from both sides of the branch pipe, and the protruding "U" part in the middle can press the pad to fix the product. Symmetric flanks with screw holes on both sides of the cover plate are fixed to the main body. The product is fixed linearly in the工装配合 (it seems there is a wrong expression here, maybe it should be "fixture cooperation"), effectively avoiding the problem of unstable clamping and positioning.
[0022] (5) The alignment speed is increased from 4 hours per piece before using the fixture to 0.5 hours per piece, effectively improving the processing efficiency and ensuring the accuracy and surface quality of the milling machining reference of the part. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 It is a three-dimensional view of the milling reference process equipment for the branch pipe forging state.
[0024] Figure 2 It is an exploded view of the milling reference process equipment for the branch pipe forging state.
[0025] Figure 3 It is a schematic diagram of the main view direction of the process equipment main body.
[0026] Figure 4 It is a schematic diagram of the俯视方向 (it seems there is a wrong expression here, maybe it should be "top view direction") structure of the process equipment main body.
[0027] Figure 5 It is a sectional view taken along the A-A direction of Circle 3.
[0028] Figure 6 This is a schematic diagram of the structure of the cover plate for process equipment from the front view.
[0029] Figure 7 for Figure 4 Sectional view along direction AA.
[0030] Figure 8 for Figure 4 BB-direction cross-section.
[0031] Figure 9 A three-dimensional view of the cover plate for the process equipment.
[0032] Figure 10 This is a schematic diagram of the structure of the process equipment pad from the front view.
[0033] Figure 11 This is a schematic diagram of the structure of the process equipment pad from the left view.
[0034] Figure 12 This is a top view of the structure of the process equipment pad.
[0035] Figure 13 A three-dimensional view of the process equipment pad. Detailed Implementation
[0036] The present application will now be described in further detail with reference to the accompanying drawings and specific embodiments.
[0037] Figure 1 This application illustrates a process equipment for milling the reference datum of a liquid rocket engine branch pipe forging, according to an embodiment of the present application. Figure 2 This is an exploded view of the process equipment. The process equipment may include a main body 1, a cover plate 4, a pad block 6, and bolts.
[0038] The main body 1 is a turntable structure. One side of the main body 1 has a central shaft that connects to the center hole of the turntable chuck for positioning and tool rotation, and is connected to the worktable surface using bolts 3. The other side has a curved groove machined to support and position part 2, determining the reference coordinates of part 2. In some embodiments, reference... Figure 2 The lower half of the main body has a special structure, with symmetrical sides and the same angle as the nozzles on both sides of the branch pipe. It has circular grooves on both sides, which are the same as the outer diameter of the nozzles on both sides of the branch pipe, and are used to fix the outer surface of the branch pipe.
[0039] The cover plate 4 can be in a "U" shape. The cover plate 4 includes two first cover plate parts connected to the main body 1 and a second cover plate part for pressing the part 2. The two first cover plate parts are located on both sides of the second cover plate part, and together with the second cover plate part form the "U" structure of the cover plate 4. The first cover plate part cooperates with the fixed mounting surface on the main body 1 and is connected to the main body 1 by bolts 5. The height of the second cover plate part is higher than that of the first cover plate part, and the second cover plate part has a cavity for accommodating the part 2 and the spacer block 6. The spacer block is arranged between the cover plate 4 and the part 2. The top end of the second cover plate part has a through hole, and the part 2 or the upper surface of the spacer block 6 is pressed by passing a bolt 7 through this through hole, so that the lower surface of the part 2 closely adheres to the curved surface groove of the main body 1, which is convenient for disassembling the part.
[0040] In some embodiments, as Figures 10 to 13 shown, the spacer block 6 can be in an L shape. The main body part of the spacer block 6 and the side close to the part 2 are arc-shaped, which is used to match the outer surface of the part 2. The main body part of the spacer block 6 also has a protruding part facing away from the part 2. This protruding part buckles the end face of the cover plate 4 to achieve the positioning of the spacer block 6.
[0041] In some embodiments, the main body 1 is processed from a whole bar, the outer circle runout is not more than 0.01 mm, and the parallelism requirement between the surfaces of the main body 1 is not more than 0.03 mm. The main body 1 has good rigidity itself, and there is a central axis on one side, which is connected to the center hole of the turntable chuck; the curved surface groove of the main body 1 provides a concave cavity with an angle of 113° and a radius of R14.7 for the protruding side of the part 2, effectively reducing the alignment time and realizing the rapid positioning and clamping of the workpiece.
[0042] In some embodiments, the part 2 is placed in the curved surface groove of the main body 1. The side surface and the bottom curved surface groove of the main body 1 are used to fit the outer surface of the part 2, and the clamping is tight, which can fix the product and prevent the part from being deformed due to the pressing force at the same time.
[0043] In some embodiments, after the workpiece is positioned, it is connected to the main body 1 through the cover plate 4 and the bolts 5, and a spacer block is used in the part 2 and the cover plate 4. By tightening the bolt 7, the part is pressed tightly so that the part will not be displaced or deformed.
[0044] The principle of the above scheme is as follows: the main body spindle Φ40-0.05~0.15mm is clamped in the center hole of the rotary table chuck, and the parallelism between the surfaces of the main body is required to be no greater than 0.03mm. One side of the part is close to the cavity of the main body, i.e., at 113°, R14.7 mm position; the aluminum pad has an R67.75 mm arc surface, which is consistent with the size of the other side of the part, and can fit with the forging surface of the part for positioning; bolts are used to connect the cover plate to the main body, which can also serve to press the aluminum pad, thereby fixing and supporting the part. The reference surface is milled using a CNC machining center. The center of the tooling and the workpiece is balanced on the machine tool spindle. The product is mounted on the tooling to process the reference. The alignment speed is increased from 4H / piece before using the tooling to 0.5H / piece, which effectively improves the processing efficiency and ensures the accuracy and surface quality of the milled reference of the part.
[0045] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope defined in the claims of the present invention.
Claims
1. A process equipment for milling the reference datum of a liquid rocket engine branch pipe forging, characterized in that, Includes main body (1), cover plate (4), pad (6); main body (1) is a turntable structure, with a central shaft on one side of the main body (1), which is connected to the central hole of the turntable chuck for positioning and tool rotation, and is connected to the worktable surface by bolts (3); The other side is machined with a curved groove to support and position the part (2) and determine the reference coordinates of the part (2); the cover plate (4) is fitted with the fixed mounting surface on the main body (1) and connected to the main body (1) by bolts (5); the pad (6) is set between the cover plate (4) and the part (2); the upper surface of the part (2) or the pad (6) is pressed by bolts (7) passing through the cover plate (4) so that the lower surface of the part (2) is in close contact with the curved groove of the main body (1).
2. The process equipment according to claim 1, characterized in that, The main body (1) is symmetrical on both sides. The angle of the curved groove is the same as the angle formed by the nozzles on both sides of the branch pipe. It has circular grooves on both sides, which are the same as the outer diameter of the nozzles on both sides of the branch pipe, and are used to fix the outer surface of the branch pipe.
3. The process equipment according to claim 1, characterized in that, Part (2) is placed in the curved groove of the main body (1). The curved grooves on the side and bottom of the main body (1) are used to fit the outer surface of part (2) and clamp it tightly. While fixing the product, the clamping force prevents the part (2) from deforming.
4. The process equipment according to claim 1, characterized in that, The cover plate (4) includes two first cover plate parts connected to the main body (1) and a second cover plate part for pressing the parts (2); the two first cover plate parts are located on both sides of the second cover plate part, forming a "V" structure of the cover plate (4) together with the second cover plate part.
5. The process equipment according to claim 4, characterized in that, The second cover plate portion is higher than the first cover plate portion, and the second cover plate portion has a cavity for accommodating the part (2) and the pad (6).
6. The process equipment according to claim 1, characterized in that, The pad (6) includes a main body and a protruding part to form an L-shaped structure; the main body and the part (2) cooperate, and the protruding part protrudes from the main body away from the part (2), and the protruding part fastens the end face of the cover plate (4) to realize the installation and positioning of the pad (6).
7. The process equipment according to claim 6, characterized in that, The main body of the pad (6) is arc-shaped on the side near the part (2).
8. The process equipment according to claim 1, characterized in that, The pad (6) is an aluminum pad.
9. The process equipment according to claim 1, characterized in that, The main body (1) is made of a single bar material, with an outer circle runout of no more than 0.01 mm and a parallelism requirement of no more than 0.03 mm between the surfaces of the main body (1).
10. The process equipment according to claim 1, characterized in that, The curved groove of the main body (1) provides a concave cavity positioning of 113°, R14.7 for the protruding side of the part (2).