A forging process for long neck flange

Abstract

The present invention relates to the field of flange technology, specifically to a forging process for long-neck flanges, comprising the following steps: cutting, heating, upsetting, and stretching a rod-shaped raw material to form a raw material blank; punching a stepped hole from the long diameter section of the raw material blank, determining the depth of the large hole section of the stepped hole according to the size of the long diameter section and the flange section of the long neck flange, and determining the diameter of the small hole section of the stepped hole according to the forging ratio of the flange section of the long neck flange and the depth of the large hole section; the beneficial effect is: the forging process for the long-neck flange proposed by the present invention cuts a guide groove in the bolt hole for installing a rubber plug strip, one end of the rubber plug strip is integrally formed on the surface of the sealing gasket, and the other end is integrally formed with a rubber clamp strip. This design not only realizes the pre-limiting of the bolt to prevent the bolt from loosening, but also clamps the rubber clamp strip between the nut and the flange section when the bolt is tightened, acting as an elastic gasket, effectively improving the connection sealing and stability.

Description

Technical Field

[0001] The invention relates to the field of flanges, in particular to a forging process for long-neck flanges. Background Art

[0002] As an important component for connecting pipes and equipment, long-neck flanges are widely used in the petroleum, chemical, machinery and other industries. The traditional long-neck flange forging process usually includes multiple steps such as raw material preparation, heating, forging, machining, etc. However, in actual applications, the connection sealing and stability of long-neck flanges have always been the focus of industry attention. The traditional connection method is mainly fastened by bolts and nuts, but during long-term use, due to factors such as vibration and temperature changes, the bolts are easy to loosen, resulting in reduced connection sealing and even leakage.

[0003] In addition, the utilization rate and forging efficiency of raw materials in the forging process of traditional long-neck flanges need to be improved. The steps of cutting, heating, forging and other steps of raw materials often have problems such as high energy consumption, complex processes and low yield. At the same time, the intersection of the flange section and the long diameter section of the long-neck flange is prone to become a stress concentration point, affecting the strength and stability of the overall structure. Summary of the invention

[0004] The object of the present invention is to provide a forging process for a long-neck flange to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a forging process for a long neck flange, the method comprising the following steps:

[0006] The rod-shaped raw material is cut, heated, upset and stretched to form a raw material blank;

[0007] Punching a stepped hole from the long diameter section of the raw material blank, determining the depth of the large hole section of the stepped hole according to the size of the long diameter section and the flange section of the long neck flange, and determining the diameter of the small hole section of the stepped hole according to the forging ratio of the flange section of the long neck flange and the depth of the large hole section, so as to form a primary blank of the long neck flange;

[0008] The flange section of the primary blank is die-forged to form a flange portion, thereby forming a flange blank of a long-neck flange;

[0009] Cut and level the flange end face of the flange segment;

[0010] Punching the flange section to form a through hole inside the flange blank that penetrates the large hole section; using a splicing tool, the flange end faces of the two flange blanks that have been leveled and punched are spliced ​​together to form a spliced ​​part;

[0011] The inner hole of the assembled parts is formed by using a ring rolling device to form the inner hole shape of the long neck flange;

[0012] Punch holes in the flange section near the outer ring to form bolt holes, and cut two symmetrically distributed lead-in grooves in the bolt holes for installing rubber plug strips;

[0013] A reserved groove is punched out on the side of the flange section away from the long diameter section for installing a sealing gasket;

[0014] A reinforcing welding rod is arranged outside the outer ring of the hinge between the flange section and the long diameter section.

[0015] Preferably, there are a plurality of bolt holes, the plurality of bolt holes are distributed in a circle with the long diameter section as the central axis, and the intervals between two adjacent bolt holes are equal.

[0016] Preferably, the reserved groove is an annular groove, and the reserved groove is connected to a plurality of bolt holes.

[0017] Preferably, the length of the long side of the introduction groove is equal to the hole depth of the bolt hole.

[0018] Preferably, the sealing gasket is an annular plate structure, the outer diameter of the sealing gasket is smaller than the outer diameter of the reserved groove, the inner diameter of the sealing gasket is larger than the inner diameter of the reserved groove, and the thickness of the sealing gasket is greater than the depth of the reserved groove.

[0019] Preferably, the surface of the sealing gasket is provided with a plurality of perforations, and the perforations correspond to the bolt holes one by one.

[0020] Preferably, the rubber plug strip corresponds to the introduction groove one by one, the rubber plug strip is inserted in the introduction groove, one end of the rubber plug strip is integrally formed on the surface of the sealing gasket, the height of the rubber plug strip is greater than the height of the introduction groove, and the long side length of the rubber plug strip is equal to the long side length of the introduction groove.

[0021] Preferably, a rubber clamp strip is integrally formed at the other end of the rubber plug strip, and the rubber clamp strip extends out of the bolt hole and abuts against the surface of the flange section.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] The forging process for the long-neck flange proposed in the present invention cuts a guide groove in the bolt hole for installing a rubber plug strip, one end of the rubber plug strip is integrally formed on the surface of the sealing gasket, and the other end is integrally formed with a rubber clamp strip. This design not only realizes the pre-limiting of the bolt to prevent the bolt from loosening, but also acts as an elastic gasket by clamping the rubber clamp strip between the nut and the flange section when the bolt is tightened, effectively improving the sealing and stability of the connection. The design of the reserved groove enables the sealing gasket to be firmly installed on the flange section. When the bolt is tightened, the sealing gasket is clamped and deformed and retracted into the reserved groove, further enhancing the sealing of the connection. A reinforcing welding rod is provided at the outer ring of the intersection of the flange section and the long diameter section. Through welding reinforcement, the strength and stability of the intersection are effectively improved, the stress concentration phenomenon is reduced, and the service life of the long-neck flange is extended. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the structure of the present invention;

[0025] Figure 2 This is a schematic diagram of the connection structure of the flange section and the sealing gasket of the present invention;

[0026] Figure 3 It is a front view of the structure of the present invention;

[0027] Figure 4 for Figure 3 A schematic diagram of the structure enlarged at AA in the middle;

[0028] Figure 5 for Figure 4 A magnified schematic diagram of the structure in the middle;

[0029] Figure 6 This is a schematic diagram of the sealing gasket structure of the present invention;

[0030] Figure 7 It is a schematic diagram of the connection structure of the flange section and the long diameter section of the present invention;

[0031] Figure 8 The figure is a flow chart of the method of the present invention.

[0032] In the figure: flange section 1, long diameter section 2, bolt hole 3, reserved groove 4, introduction groove 5, reinforcement welding rod 6, sealing gasket 7, through hole 8, rubber plug strip 9, rubber clamp strip 10. DETAILED DESCRIPTION

[0033] In order to make the purpose and technical solution of the present invention clearly and completely described, and the advantages more clearly understood, the embodiments of the present invention are further described in detail with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are part of the embodiments of the present invention, rather than all of the embodiments, and are only used to explain the embodiments of the present invention, and are not used to limit 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.

[0034] See also Figure 1-Figure 8 The present invention provides a technical solution: a forging process for a long-neck flange, the method comprising the following steps:

[0035] Raw material pretreatment: First, the rod-shaped raw material is precisely cut and fully heated, followed by upsetting and drawing operations. This series of steps is aimed at shaping the raw material into a preliminary raw material billet, laying a solid foundation for subsequent processing.

[0036] Step hole punching: Then, a step hole is punched out on the long diameter section 2 of the raw material blank according to the design requirements of the long neck flange. The key to this step is to accurately calculate the depth of the large hole section, which must match the size of the long diameter section 2 and the flange section 1 of the long neck flange. At the same time, the diameter of the small hole section in the step hole is determined according to the forging ratio of the flange section 1 and the depth of the large hole section, thereby completing the preparation of the primary blank of the long neck flange.

[0037] Die forging flange part: Subsequently, the flange section 1 of the primary blank is die forged to form a flange part of the required shape. At this time, the long-neck flange has taken shape, that is, the flange blank of the long-neck flange. End face leveling: In order to ensure the flatness of the flange end face, the flange end face of the flange section 1 needs to be cut and leveled to provide an accurate reference for subsequent processing and assembly.

[0038] Internal through hole formation: Next, the flange segment 1 is punched to form a through hole that penetrates the large hole segment. This step prepares for subsequent splicing and inner hole forming.

[0039] Splicing and inner hole forming: Using a special splicing tool, the flange end faces of two flange blanks that have been leveled and punched are spliced ​​together to form a spliced ​​piece. Subsequently, advanced ring rolling equipment is used to form the inner hole of the spliced ​​piece to accurately shape the inner hole shape of the long-neck flange. Bolt hole and lead-in groove processing: In the part of the flange section 1 close to the outer ring, a plurality of bolt holes 3 are punched out that are evenly distributed in a circle with the long diameter section 2 as the central axis. Two symmetrically distributed lead-in grooves 5 are cut in each bolt hole 3 for installing a rubber plug strip 9. The design of the lead-in groove 5 is ingenious, and the length of its long side matches the hole depth of the bolt hole 3, ensuring that the rubber plug strip 9 can be firmly inserted.

[0040] Application of rubber plug strip and rubber clamp strip: The rubber plug strip 9 is integrally formed with the sealing gasket 7, and its height is slightly higher than the introduction groove 5, and the long side length is equal. The other end of the rubber plug strip 9 is integrally formed with a rubber clamp strip 10. When the bolt passes through the bolt hole 3 and is locked, the rubber clamp strip 10 can be clamped between the nut and the flange section 1, playing the role of an elastic gasket, enhancing the stability and sealing of the connection.

[0041] Installation of reserved groove and sealing gasket: On the side of flange section 1 away from long diameter section 2, a reserved groove 4 in the shape of an annular groove is punched out, and the groove is connected with a plurality of bolt holes 3. The sealing gasket 7 is an annular plate structure, and its outer diameter is smaller than the outer diameter of the reserved groove 4, and its inner diameter is larger than the inner diameter of the reserved groove 4, and its thickness is larger than the depth of the reserved groove 4. The sealing gasket 7 is provided with through holes 8 corresponding to the bolt holes 3 one by one, so as to facilitate the passing and fixing of the bolts.

[0042] Reinforcement treatment: Finally, a reinforcing welding rod 6 is added at the outer ring of the hinge between the flange section 1 and the long diameter section 2 to further enhance the structural strength and stability of the junction.

[0043] Through the above detailed steps, the present invention not only optimizes the forging process of the long-neck flange, but also significantly improves the connection stability and sealing performance of the long-neck flange through a series of innovative designs, such as the application of rubber plug strips 9 and rubber clamp strips 10, the cooperation of reserved grooves 4 and sealing gaskets 7, and the addition of reinforcing welding rods 6, providing strong support for engineering technology in related fields. Although the embodiments of the present invention have been shown and described, it is understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A forging process for a long neck flange, characterized in that: The method comprises the following steps: The rod-shaped raw material is cut, heated, upset and stretched to form a raw material blank; Punching a stepped hole from the long diameter section 2 of the raw material blank, determining the depth of the large hole section of the stepped hole according to the size of the long diameter section 2 and the flange section 1 of the long neck flange, and determining the diameter of the small hole section of the stepped hole according to the forging ratio of the flange section 1 of the long neck flange and the depth of the large hole section, so as to form a primary blank of the long neck flange; The flange section 1 of the primary blank is die-forged to form a flange portion, thereby forming a flange blank of a long-neck flange; the flange end face of the flange section 1 is cut and leveled; Punching the flange section 1 to form a through hole inside the flange blank that penetrates the large hole section; using a splicing tool, the flange end faces of the two flange blanks that have been leveled and punched are spliced ​​together to form a spliced ​​part; The inner hole of the assembled parts is formed by using a ring rolling device to form the inner hole shape of the long neck flange; A bolt hole (3) is punched in the flange section (1) near the outer ring, and two symmetrically distributed guide grooves (5) are cut in the bolt hole (3) for installing a rubber plug strip (9); A reserved groove (4) is punched out on the side of the flange section (1) away from the long diameter section (2) for installing a sealing gasket (7); A reinforcing welding rod (6) is arranged outside the outer ring of the hinged joint between the flange section (1) and the long diameter section (2).

2. A forging process for a long neck flange according to claim 1, characterized in that: A plurality of bolt holes (3) are provided, and the plurality of bolt holes (3) are distributed in a circle with the long diameter section (2) as the central axis, and the spacing between two adjacent bolt holes (3) is equal.

3. The forging process for a long neck flange according to claim 1, characterized in that: The reserved groove (4) is an annular groove, and the reserved groove (4) is connected to a plurality of bolt holes (3).

4. A forging process for a long neck flange according to claim 1, characterized in that: The length of the long side of the introduction groove (5) is equal to the hole depth of the bolt hole (3).

5. The forging process for a long neck flange according to claim 1, characterized in that: The sealing gasket (7) is an annular plate-shaped structure, the outer diameter of the sealing gasket (7) is smaller than the outer diameter of the reserved groove (4), the inner diameter of the sealing gasket (7) is larger than the inner diameter of the reserved groove (4), and the thickness of the sealing gasket (7) is greater than the depth of the reserved groove (4).

6. A forging process for a long neck flange according to claim 1, characterized in that: The surface of the sealing gasket (7) is provided with a plurality of through holes (8), and the through holes (8) correspond to the bolt holes (3) one by one.

7. The forging process for a long neck flange according to claim 1, characterized in that: The rubber plug strip (9) corresponds to the introduction groove (5) one by one, the rubber plug strip (9) is inserted into the introduction groove (5), one end of the rubber plug strip (9) is integrally formed on the surface of the sealing pad (7), the height of the rubber plug strip (9) is greater than the height of the introduction groove (5), and the length of the long side of the rubber plug strip (9) is equal to the length of the long side of the introduction groove (5).

8. The forging process for a long neck flange according to claim 1, characterized in that: The other end of the rubber plug strip (9) is integrally formed with a rubber clamp strip (10), and the rubber clamp strip (10) extends out of the bolt hole (3) and abuts against the surface of the flange section (1).

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