Seamless fitting processing technology for sectioned graphite sealing ring

Abstract

The invention discloses a processing technology for seamless fitting of a sectioned graphite sealing ring, and belongs to the field of machining. A sectioning ring bonding technology is adopted, a graphite blank is sectioned, then the sectioned graphite blank forms two semi-rings, the two semi-rings are bonded into a whole ring and then processed, and the maximum diameter of a product is expanded to be D = 1000 mm; meanwhile, back-to-back grinding is adopted to improve the sealing performance of the bonding surfaces of the two valve rings, the bonding rate of the bonding surfaces reaches 85% or above, and the designed numerical control vertical lathe clamping tool enables the product not to be suspended and not to deform.

Description

Technical Field

[0001] The invention belongs to the field of mechanical processing, and in particular relates to a processing technology for seamlessly fitting a split graphite sealing ring. Background Art

[0002] Graphite sealing rings are commonly used components in the engine field. For easy installation and good sealing effect, they are usually processed into petal forms. Existing petal graphite sealing rings are first processed into a full circle and then directly split into petals. The full circle sealing rings are not bonded or ground on the fitting surface, resulting in a large gap on the fitting surface of the full ring after being processed into a finished product. The maximum size that can be directly processed is small, D < 500mm, and the fitting rate is low, about 40%. Summary of the invention

[0003] In order to solve the technical problems existing in the prior art, the present invention provides a processing technology for seamless bonding of split-petal graphite sealing rings. The present invention adopts the split-petal ring bonding technology (such as dividing into 4 petals, bonding the 4 petals into 2 petals respectively, and then bonding them into a whole ring for processing), and the maximum diameter of the product is expanded to D=1000mm; back-to-back grinding improves the sealing performance of the bonding surface of the two petal rings, and the bonding rate of the bonding surface reaches more than 85%.

[0004] The present invention provides a processing technology for seamlessly fitting a split-flap graphite sealing ring, comprising the following steps: Dividing the graphite blank into a plurality of first sector-shaped plates having the same thickness; The first sector-shaped sheet is turned for the first time to turn the outer diameter, inner diameter and sector-shaped end face to obtain the second sector-shaped sheet, ensuring that the chord length of the second sector-shaped sheet is not less than the design requirement; Impregnating the second sector-shaped sheet with epoxy resin; The second fan-shaped sheet material after impregnation is turned for the second time to turn the outer diameter, inner diameter and fan-shaped end face to obtain the third fan-shaped sheet material, ensuring that the chord length of the third fan-shaped sheet material is not less than the design requirement; Grinding the fan-shaped end surface of the third fan-shaped plate material to obtain a fourth fan-shaped plate material; Mill the chord length and Z-shaped bonding point of the fourth sector-shaped sheet to obtain the fifth sector-shaped sheet, ensuring that the fifth sector-shaped sheet can be bonded into a full circle; The fifth sector-shaped sheet is bonded to form a full-circle sealing ring.

[0005] Preferably, after forming the full-circle sealing ring, the following steps are also included: Clean the adhesive; Flat grinding and bonding to form the end face of the full-circle sealing ring; Finish turning of full-circle sealing rings; Grind the sealing end face of the full-circle sealing ring.

[0006] Preferably, after flat grinding and bonding the end face of the full-circle sealing ring and before fine turning the full-circle sealing ring, the process also includes inspecting the flat-ground grinding surface, requiring the parallelism error of the end face to be ≤0.02 mm.

[0007] Preferably, after the full-circle sealing ring is formed by precision turning and before the sealing end face of the full-circle sealing ring is ground, an intermediate inspection step is also included to check whether the full-circle sealing ring meets the design requirements.

[0008] Preferably, after the full-circle sealing ring is formed by fine turning, the three-coordinate method is used to check whether the size and shape and position tolerance accuracy of the full-circle sealing ring meet the design requirements.

[0009] Preferably, for a split graphite sealing ring composed of two half rings, after bonding to form a full-circle sealing ring, the following steps are further included: Divide the full-circle sealing ring into two half rings by wire cutting; Mill the fitting surfaces of the two half rings; The two half rings are placed back to back and fixed using a back-to-back tooling, and then the mating surfaces of the two half rings are ground.

[0010] Preferably, when the full-circle sealing ring is formed by precision turning, the full-circle sealing ring is clamped by a full-ring clamping tool, and the full-ring clamping tool includes a tooling pad, multiple tooling pressure plates, and a process chuck; the tooling pad and the process chuck are circular, and the outer ring of the process chuck matches the inner ring of the tooling pad, and the process chuck is higher than the upper surface of the tooling pad, and the full-circle sealing ring can be fixed on the tooling pad through the tooling pressure plate, and multiple tooling pressure plates are fixed on the machine tool workbench by T-screws; the outer ring of the process chuck matches the inner ring of the full-circle sealing ring.

[0011] Preferably, a saw is used to separate the graphite blank into sheets of equal thickness.

[0012] Preferably, a CNC vertical lathe is used for the first turning and the second turning.

[0013] Preferably, there are subsequent auxiliary processes, including cleaning, marking, final inspection, and packaging.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention first performs petal division, and then utilizes the bonding technology of the petal ring (bonding multiple petals into two petals separately and processing the whole ring, or directly bonding multiple petals into a whole ring and processing), the maximum diameter of the product is expanded to D=1000mm, which is much larger than the existing diameter.

[0015] 2. The present invention grinds the two half rings back to back, thereby improving the sealing performance of the bonding surfaces of the two half rings, and the bonding rate of the bonding surface reaches more than 85%.

[0016] 3. The present invention designs a tooling for fine turning the whole ring. First, the outer ring and one surface of the whole ring are fine turned to the process chuck. After processing to the designed size, the tooling pressure plate is pressed against the whole ring and tightened by screws. Then the process chuck is removed, the screws are kept tightened, and the inner ring of the whole ring is processed to the designed size. Then, it is turned over and the other surface and the inner and outer rings are processed by the same process. In this processing method, the product is not suspended in the air and will not be deformed. In the traditional clamping method, the inner and outer diameters of the product are generally fixed by three claws, tops, etc., and the product is suspended in the air. The traditional clamping method (such as Fig. 9 As shown, the figure includes multiple conventional center clamps 5) which are prone to generate processing stress and deformation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A top view of a sheet material after the first lathe according to an embodiment of the present invention; Figure 2 A front view of a sheet material after the first lathe according to an embodiment of the present invention; Figure 3 A top view of a sheet material after the second lathe according to an embodiment of the present invention; Figure 4 A front view of a sheet material after a second lathe according to an embodiment of the present invention; Figure 5 This is a three-dimensional schematic diagram of full-circle bonding according to an embodiment of the present invention; Figure 6 It is a three-dimensional schematic diagram of a full circle formed by bonding two half rings according to an embodiment of the present invention; Figure 7 It is a three-dimensional schematic diagram of the fitting surfaces of two half rings milled when the final product of one embodiment of the present invention is in the form of a non-integral ring (a split graphite sealing ring composed of two half rings); Figure 8 It is a three-dimensional schematic diagram of the back-to-back grinding and bonding surfaces of two half rings when the final product of an embodiment of the present invention is in a non-integral ring form (a split graphite sealing ring composed of two half rings); Fig. 9 It is a three-dimensional schematic diagram of the traditional clamping method used in the CNC vertical lathe in the prior art; Fig.10 It is a three-dimensional schematic diagram of an embodiment of the present invention using the back-to-back tooling designed by the present invention to clamp a full-circle sealing ring.

[0018] In the figure, 1-tooling pad, 2-tooling pressure plate, 3-process chuck, 4-1-first half ring, 4-2-second half ring, 5-conventional top clamping, 6-Z-shaped bonding point, 7-I-shaped bonding point, 8-back-to-back tooling, 9-clamping screw, 10-fitting surface of half ring, 11-full circle sealing ring. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. The described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] The present invention provides a processing technology for seamlessly fitting a split-flap graphite sealing ring, comprising the following steps: The graphite blank is divided into a plurality of first sector-shaped sheets of the same thickness; Figure 1 and 2 As shown; The first sector-shaped sheet is turned for the first time to turn the outer diameter, inner diameter and sector-shaped end face to obtain the second sector-shaped sheet, such as Figure 3 and 4 As shown, the chord length of the second sector sheet is guaranteed to be no less than the design requirement; The second sector-shaped sheet is impregnated with epoxy resin; the epoxy resin is an impregnation material in the graphite blank; The second fan-shaped sheet material after impregnation is turned for the second time to turn the outer diameter, inner diameter and fan-shaped end face to obtain the third fan-shaped sheet material, ensuring that the chord length of the third fan-shaped sheet material is not less than the design requirement; Grinding the fan-shaped end surface of the third fan-shaped plate material to obtain a fourth fan-shaped plate material; Milling the chord length and the Z-shaped bonding point 6 of the fourth sector-shaped sheet material to obtain the fifth sector-shaped sheet material, ensuring that the fifth sector-shaped sheet material can be bonded into a full circle; The fifth sector-shaped sheet is bonded to form a full-circle sealing ring 11 .

[0021] According to a specific embodiment of the present invention, there are two specific situations to ensure that the fan-shaped sheet material after milling can be bonded into a full circle. One is that both ends of the fan-shaped sheet material have a Z-shaped bonding point 6, and the two are bonded to form a full circle, such as Figure 5 As shown; the other is that one part of the fan-shaped sheet has a Z-shaped bonding point 6 at both ends, and the other part of the fan-shaped sheet has a neat straight bonding point 7 at one end and a Z-shaped bonding point 6 at the other end, and the end with the straight bonding point 7 is attached to the straight bonding point 7 of another fan-shaped sheet. Figure 6 shown.

[0022] According to a specific embodiment of the present invention, after forming the full-circle sealing ring, the following steps are also included: Clean the adhesive; Flat grinding and bonding to form the end surface of the full-circle sealing ring 11; Finish turning the full-circle sealing ring 11 into shape; The sealing end surface of the full-circle sealing ring 11 is ground.

[0023] According to a specific embodiment of the present invention, after flat grinding and bonding the end face of the full-circle sealing ring 11 and before fine turning the full-circle sealing ring 11, the process also includes checking the flat-ground grinding surface, requiring the parallelism error of the end face to be ≤0.02mm.

[0024] According to a specific embodiment of the present invention, after the full-circle sealing ring 11 is formed by precision turning and before the sealing end surface of the full-circle sealing ring 11 is ground, an intermediate inspection step is also included to check whether the full-circle sealing ring 11 meets the design requirements.

[0025] According to a specific embodiment of the present invention, after the full-circle sealing ring 11 is formed by precision turning, the three-coordinate method is used to check whether the size and shape and position tolerance accuracy of the full-circle sealing ring 11 meet the design requirements.

[0026] According to a specific embodiment of the present invention, for a split graphite sealing ring composed of two half rings, after bonding to form a full-circle sealing ring, the following steps are also included: The full-circle sealing ring 11 is divided into two half-rings (a first half-ring 4-1 and a second half-ring 4-2) by wire cutting; Mill the fitting surfaces 10 of the two half rings, such as Figure 7 As shown; Use the back-to-back fixture 8 to place the two half rings back to back and use the clamping screws 9 to fix them. Figure 8 As shown, the mating surfaces of the two half rings are then ground, which surfaces are also the mating surfaces.

[0027] According to a specific embodiment of the present invention, when the full-circle sealing ring 11 is formed by precision turning, the full-circle sealing ring 11 is clamped by a full-ring clamping tool, and the full-ring clamping tool includes a tool pad 1, multiple tool pressure plates 2, and a process chuck 3; the tool pad 1 and the process chuck are circular, and the outer ring of the process chuck 3 matches the inner ring of the tool pad 1, and the full-circle sealing ring 11 can be fixed on the tool pad 1 through the tool pressure plate 2, and multiple tool pressure plates 2 are fixed on the machine tool workbench by T-screws; the outer ring of the process chuck 3 matches the inner ring of the full-circle sealing ring 11, such as Fig.10 As shown, the whole ring clamping tool is put on after the whole circle sealing ring 11 is placed.

[0028] According to a specific embodiment of the present invention, a saw is used to divide the graphite blank into sheets of equal thickness.

[0029] According to a specific embodiment of the present invention, a CNC vertical lathe is used for the first turning and the second turning.

[0030] According to a specific embodiment of the present invention, there are subsequent auxiliary processes including cleaning, marking, final inspection and packaging.

[0031] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A processing technology for seamlessly fitting a split graphite sealing ring, characterized in that: The steps include: Dividing the graphite blank into a plurality of first sector-shaped plates having the same thickness; The first sector-shaped sheet is turned for the first time to turn the outer diameter, inner diameter and sector-shaped end face to obtain the second sector-shaped sheet, ensuring that the chord length of the second sector-shaped sheet is not less than the design requirement; Impregnating the second sector-shaped sheet with epoxy resin; The second fan-shaped sheet material after impregnation is turned for the second time to turn the outer diameter, inner diameter and fan-shaped end face to obtain the third fan-shaped sheet material, ensuring that the chord length of the third fan-shaped sheet material is not less than the design requirement; Grinding the fan-shaped end surface of the third fan-shaped plate material to obtain a fourth fan-shaped plate material; Mill the chord length and Z-shaped bonding point of the fourth sector-shaped sheet to obtain the fifth sector-shaped sheet, ensuring that the fifth sector-shaped sheet can be bonded into a full circle; The fifth sector-shaped sheet is bonded to form a full-circle sealing ring.

2. The seamless bonding processing technology of the split graphite sealing ring according to claim 1 is characterized in that: After forming the full-circle sealing ring, the following steps are also included: Clean the adhesive; Flat grinding and bonding to form the end face of the full-circle sealing ring; Finish turning of full-circle sealing rings; Grind the sealing end face of the full-circle sealing ring.

3. The seamless bonding processing technology of the split-flap graphite sealing ring according to claim 2 is characterized in that: After flat grinding and bonding the end face of the full-circle sealing ring, before fine turning the full-circle sealing ring, it also includes checking the flat-ground grinding surface, requiring the parallelism error of the end face to be ≤0.02mm.

4. The seamless bonding processing technology of the split graphite sealing ring according to claim 2 is characterized in that: After the full-circle sealing ring is formed by precision turning, an intermediate inspection step is also included before the sealing end face of the full-circle sealing ring is ground to check whether the full-circle sealing ring meets the design requirements.

5. The seamless bonding process of the split graphite sealing ring according to claim 4 is characterized in that: After the full-circle sealing ring is formed by fine turning, the three-coordinate method is used to check whether the size and shape and position tolerance accuracy of the full-circle sealing ring meet the design requirements.

6. The seamless bonding processing technology of the split graphite sealing ring according to any one of claims 2 to 5 is characterized in that: For a split graphite sealing ring composed of two half rings, after bonding to form a full-circle sealing ring, the following steps are also included: Divide the full-circle sealing ring into two half rings by wire cutting; Mill the fitting surfaces of the two half rings; The two half rings are placed back to back and fixed using a back-to-back tooling, and then the mating surfaces of the two half rings are ground.

7. The seamless bonding process of the split graphite sealing ring according to claim 2 is characterized in that: When the full-circle sealing ring is formed by precision turning, the full-circle sealing ring is clamped by a full-ring clamping tool, and the full-ring clamping tool includes a tooling pad, multiple tooling pressure plates, and a process chuck; the tooling pad and the process chuck are circular, and the outer ring of the process chuck matches the inner ring of the tooling pad, and the process chuck is higher than the upper surface of the tooling pad, and the full-circle sealing ring can be fixed on the tooling pad through the tooling pressure plate, and multiple tooling pressure plates are fixed on the machine tool workbench by T-screws; the outer ring of the process chuck matches the inner ring of the full-circle sealing ring.

8. The seamless bonding process of the split graphite sealing ring according to claim 1 is characterized in that: The graphite blank is cut into sheets of equal thickness using a saw.

9. The seamless bonding process of the split graphite sealing ring according to claim 1 is characterized in that: CNC vertical lathe is used for the first and second machining.

10. The seamless bonding processing technology of the split graphite sealing ring according to any one of claims 2-5 and 7-9, characterized in that: There are also auxiliary processes afterwards, including cleaning, labeling, final inspection and packaging.

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