A spinning core mold with workpiece inner surface protection and oil cleaning function

Abstract

A spinning core mold with workpiece inner surface protection and oil cleaning function, the discharge ring is sleeved on the outer circumferential surface of the mold body, and the inner inclined surface of one end of the discharge ring is attached to the taper surface of the mold body; the threaded top ring is installed on the outer threaded surface at the end of the constant diameter section of the mold body; each sealing ring is placed on the outer circumferential surface of the constant diameter section of the mold body. The application innovatively proposes the concept of inner surface protection and oil cleaning in the design process of the spinning mold for the first time, introduces elastic sealing in the existing spinning mold design and manufacturing in the industry, and integrates the workpiece inner surface protection and oil cleaning in the spinning process, which can effectively prevent metal debris from entering between the spinning part and the core mold, avoid scratching the surface of the spinning part and the core mold, make the appearance quality of the spinning part good, the wall thickness uniform, and the service life of the core mold long, reduce the cleaning difficulty and workload of the inner surface oil stain of the workpiece, reduce the generation of chemical waste, and be suitable for automatic processing of large quantities of products.

Description

Technical Field

[0001] This invention relates to the field of spinning manufacturing, specifically a spinning mandrel with functions of protecting the inner surface of the workpiece and cleaning oil. Background Technology

[0002] With the rapid development of my country's economy, high-power spinning forming technology has been increasingly widely used in the processing of various cylindrical parts. The key process equipment required for high-power spinning—the spinning mandrel—is characterized by high precision requirements, high material hardness, high processing difficulty, long production cycle, and high cost. Currently, in the high-power spinning process, anti-wear and anti-pressure spinning oil needs to be applied to the inner surface of the workpiece and the outer surface of the mold to protect the mold and workpiece surfaces, reduce the flow resistance of the metal material, and facilitate smooth demolding. However, after the workpiece has completed spinning, a large amount of residual spinning oil needs to be cleaned from the inner surface of the spun cylindrical product, which presents the following operational inconveniences:

[0003] 1. During the spinning process, metal shavings may enter between the mandrel and the workpiece along the gap between the unloading ring and the workpiece with a large flow of coolant, damaging the inner surface of the workpiece and the outer surface of the mold, which can easily lead to product scrap and mandrel damage.

[0004] 2. Spinning cylinders are generally quite long, especially small and medium-diameter cylinders, where excessive residual spinning oil on the inner surface is difficult to clean. Existing technologies and operating methods mainly employ two supplementary post-treatment methods. One requires manual cleaning using long rods to clamp kerosene-soaked cotton yarn deep into the cylinder. This method is labor-intensive for large-scale production, operates in harsh environments, and has low cleaning efficiency. The second method involves placing the cylinder requiring surface cleaning on an automated organic solvent spraying device, followed by wiping the inner and outer surfaces after cleaning. This method has a high initial investment cost and is limited by the cylinder's size specifications.

[0005] 3. Cleaning the inner surface requires cotton yarn soaked in organic solvents such as kerosene. Kerosene is slightly toxic, flammable and explosive when exposed to open flame, and is a hazardous chemical, so there is a risk in handling it.

[0006] 4. Spinning oil and cotton yarn that have been cleaned with kerosene are chemical wastes that are harmful to the environment and need to be centrally recycled.

[0007] 5. Before the rotating wheel contacts the workpiece, the unloading ring cannot directly transmit torque to the workpiece, causing the workpiece to be easily thrown out along the mandrel axis. This results in the workpiece being unable to be positioned and unreliable continuous automated machining cannot be performed. Existing solutions are mainly: First, through the operator's precise operation, when the workpiece is found to be thrown out axially, the machine is immediately stopped and a hand tool is used to increase axial restraint; this operation is somewhat dangerous. Second, a higher viscosity grease is reapplied to the mold to increase the friction between the workpiece and the mold, preventing excessive throwing out. This method increases the workload and is not very effective for large-diameter workpieces.

[0008] By searching for the relevant patents and literature of the closest existing technology at home and abroad, the academic literature on titanium, "Spinning Process and Tooling Design of Thin-Walled Cylindrical Parts" (Yu Fengli, 2011-08, 12th National Spinning Technology Exchange Conference), mainly introduces the process calculation of spinning, the determination of spinning process parameters and the design parameters of spinning die diameter, but does not involve how to use the die to protect the inner surface of the workpiece and clean residual oil.

[0009] The utility model patent ZL201921082981.3 discloses an aluminum alloy wheel hub spinning mold that is easy to demold. It mainly describes how to demold the workpiece, and the aluminum alloy wheel hub and the spinning thin-walled cylindrical structure are different. It does not involve how to protect the inner surface of the workpiece and clean the oil.

[0010] The literature “Mandrel for Thinning Spinning of Cylindrical Parts” (Wei Lijun, Vol. 43, No. 2 & 3, 2003, Experimental Technology and Testing Machine) studied the thinning spinning process of cylindrical parts using a sliding mandrel, which improved the single radial compressive stress on the workpiece when spinning with a fixed mandrel. However, it did not cover how to protect the inner surface of the workpiece and clean the oil.

[0011] The literature “Spinning Process and Tooling Design of Thin-Walled Cylindrical Parts” (Duan Lianghui, 2011-07, Precision Forming Engineering) describes the connection between the core mold and the equipment and workpiece, and the determination of materials and working dimensions, but does not involve how to protect the inner surface of the workpiece and clean the oil.

[0012] The literature “Spinning process of cylindrical parts and its mold design” (Wang Guolin, Mold Manufacturing, 2010(010)006, P21-P24) involves the core mold size, material and performance requirements, but does not involve how to protect the inner surface of the workpiece and clean the oil.

[0013] The invention patent ZL201310511275.7 discloses a mold for spinning, which involves reducing friction and improving the heat dissipation capacity of the mold, but does not involve how to protect the inner surface of the workpiece and clean the oil.

[0014] In ZL202021982336.X, a novel structure spinning die is disclosed, which addresses a common problem of die components during the spinning process of wheel hubs, but does not address how to protect the inner surface of the workpiece and clean the oil.

[0015] ZL202120848891.1 discloses a spinning die, which involves the technology of improving material flow and reasonably controlling machining allowance during the spinning process of wheel hub, but does not involve how to protect the inner surface of the workpiece and clean the oil.

[0016] ZL202121038682.7 discloses a metal shell spinning mold, which involves a technology that uses centrifugal force and air pressure to facilitate product demolding, but does not involve how to protect the inner surface of the workpiece and clean the oil. Summary of the Invention

[0017] To address the problems of metal debris easily entering the mold body and damaging the workpiece during the existing spinning process, and the inconvenience of cleaning a large amount of residual spinning oil on the inner surface of the spinning cylinder, this invention proposes a spinning core mold with workpiece inner surface protection and oil cleaning functions.

[0018] This invention includes a mold body, a stripper ring, a threaded top ring, and a sealing ring; the sealing ring includes a YX-type rubber sealing ring for holes, a sealing ring without a retaining ring, and a Y-shaped rubber sealing ring. The stripper ring is fitted onto the outer circumferential surface of the mold body, with the inner inclined surface of one end of the stripper ring fitting against the conical surface of the mold body; the threaded top ring is installed on the external threaded surface at the end of the equal-diameter section of the mold body; the YX-type rubber sealing ring for holes, the sealing ring without a retaining ring, and the Y-shaped rubber sealing ring are sequentially placed on the outer circumferential surface of the equal-diameter section of the mold body, with the YX-type rubber sealing ring located at the end face of the stripper ring.

[0019] The inner circumferential surface of the mold body is divided into an inner conical section and an inner constant diameter section. The inner conical section has a taper of 7.125° and an axial length of 120mm. This conical section serves as the inner stop of the mold body and is used for assembly and positioning with the machine tool spindle. The inner diameter of the inner constant diameter section is 1 / 2 to 1 / 3 of the outer diameter, which is used to reduce the negative mass of the mold body.

[0020] The outer circumferential surface of the mold is functionally divided into an outer cylindrical section, an outer conical section, and an outer constant-diameter section. The inner stop section has the largest outer diameter and is the outer cylindrical section. The large-diameter end of the outer conical section connects to the outer cylindrical section, and the small-diameter end of the outer conical section connects to one end of the outer constant-diameter section. The other end of the outer constant-diameter section has a two-stage stepped surface, which serves as a Y-shaped rubber sealing ring mounting surface and an external threaded surface for mounting a threaded top ring.

[0021] The gap between the outer surface of the outer equal-diameter section of the mold body and the inner surface of the workpiece is ≤0.7mm, and the length of the outer equal-diameter section is 2 / 3 to 4 / 5 of the length of the workpiece.

[0022] The distance between the adjacent surfaces of the ringless sealing ring and the Y-shaped rubber sealing ring is 10mm to 15mm.

[0023] The retaining ring and the YX-type rubber seal for the hole are immersed in hydraulic oil at 60-70°C for 10-15 minutes before installation.

[0024] The unloading ring is a hollow rotating body. The unloading ring and the mold body are in clearance fit. One end of the outer circumferential surface of the unloading ring has a radially protruding boss, which is used as an axial force boss when the spinning machine's material feeding mechanism acts on the unloading ring axially; the end face of the boss near the workpiece is a sloped surface to avoid collision with the spinning wheel, and the taper of the sloped surface is 120°.

[0025] The inner ports at both ends of the unloading ring are flared, with the taper of the inclined surface near the inner stop of the mold body being 145°.

[0026] This invention focuses on the common problems of internal surface protection and oil removal in spinning cylindrical parts. It innovatively proposes a concept that integrates internal surface protection and oil removal for the first time in the design and manufacturing of spinning dies. It is also the first in the industry to develop and introduce an elastic sealing structure in the design and manufacturing of spinning dies. Through careful analysis of various factors before, during, and after the spinning process that can lead to metal debris scratching the workpiece and die, as well as the difficulty in cleaning residual oil, a dual-seal combination was designed, consisting of a Yx single seal at the die root and an O-ring seal combined with a Yx seal at the die end. This completely integrates internal surface protection and oil removal into the spinning process, making it particularly suitable for automated production of large-volume, clean, and pollution-free products. It completely solves the problem of scratches caused by hard foreign objects between the cylinder and the die, eliminates the separate process of cleaning the internal surface of the workpiece after unloading, reduces the number of operators and the need to clean toxic and harmful oils, and greatly improves product production efficiency.

[0027] This invention effectively prevents metal debris from entering between the spun part and the mandrel, avoiding scratches on the surfaces of both parts. Therefore, the spun part has a high-quality appearance, uniform wall thickness, and a long mandrel lifespan. Simultaneously, it cleans away a large amount of residual spinning oil from the inner surface of the workpiece during processing and unloading, significantly reducing the difficulty and workload of cleaning oil stains on the inner surface. It also prevents the mandrel from being axially ejected from the workpiece at the leading edge of the spinning process. Furthermore, it reduces the use of flammable and polluting organic solvents such as kerosene, thus reducing chemical waste generation and making it suitable for automated processing of large-volume products. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the spinning process.

[0029] Figure 2 This is a schematic diagram of the mold body structure; among which, Figure 2 'a' is the main view. Figure 2 b is Figure 2 The left view of a.

[0030] Figure 3 This is a schematic diagram of the unloading ring structure; where, Figure 3 'a' is the main view. Figure 3 b is Figure 3The left view of a.

[0031] Figure 4 This is a schematic diagram of a threaded top ring; where, Figure 4 'a' is the main view. Figure 4 b is Figure 4 A partial sectional view along direction A in section a.

[0032] Figure 5 This is a schematic diagram of a spinning mandrel.

[0033] In the diagram: 1. Mold body; 2. Unloading ring; 3. YX type rubber seal for holes; 4. Rotary wheel; 5. Workpiece; 6. Seal without retainer ring; 7. Y-shaped rubber seal; 8. Threaded top ring. Detailed Implementation

[0034] This invention relates to a spinning mandrel for spinning workpieces with an inner diameter of d4±0.1mm, and which also provides inner surface protection and oil removal functions for the workpiece.

[0035] The spinning mandrel includes a mold body 1, a stripper ring 2, a threaded top ring 8, and a sealing ring; the sealing ring includes a YX-type rubber sealing ring 3 for holes, a sealing ring without a retaining ring 6, a Y-shaped rubber sealing ring 7, and a threaded top ring 8. Wherein:

[0036] The unloading ring 2 is fitted onto the outer circumferential surface of the mold body, and the inner inclined surface of one end of the unloading ring is in contact with the conical surface of the mold body; the threaded top ring 8 is installed on the external threaded surface at the end of the equal diameter section of the mold body; the YX type rubber sealing ring 3, the ringless sealing ring 6, and the Y-shaped rubber sealing ring 7 are sequentially placed on the outer circumferential surface of the equal diameter section of the mold body, and the YX type rubber sealing ring 3 is located at the end face of the unloading ring 2.

[0037] The distance between the adjacent surfaces of the ringless sealing ring 6 and the Y-shaped rubber sealing ring 7 is 10mm to 15mm. The ringless sealing ring 6 and the YX-type rubber sealing ring 3 for the hole are then subjected to a temperature of 60-70℃. hydraulic oil Soak in water for 10-15 minutes before installation.

[0038] The mold body 1 is a hollow rotating body with a long shaft. Its inner circumferential surface is divided into an inner conical section and an inner equal-diameter section. The taper of the inner conical section is 7.125° and the axial length is 120mm. The conical section is the inner stop of the mold body 1 and is used to assemble and position it with the machine tool spindle. The inner diameter of the inner equal-diameter section is 1 / 2 to 2 / 3 of the outer diameter to reduce the negative mass of the mold body.

[0039] The outer circumferential surface of the mold body 1 is functionally divided into an outer cylindrical section, an outer conical section, and an outer equal-diameter section. The inner stop section has the largest outer diameter and is the outer cylindrical section. The large-diameter end of the outer conical section connects to the outer cylindrical section, and the small-diameter end connects to one end of the outer equal-diameter section. The other end of the outer equal-diameter section has a two-stage stepped surface, which is the mounting surface of the Y-shaped rubber sealing ring and the external thread surface for mounting the threaded top ring.

[0040] The outer cylindrical section of the mold body has a diameter of 400mm and a length of 120mm; the outer conical section has a taper of 145°; the gap between the outer surface of the outer equal-diameter section of the mold body and the inner surface of the workpiece is ≤0.7mm; and the length of the outer equal-diameter section is 2 / 3 to 4 / 5 of the length of the workpiece 5.

[0041] The outer circumferential surface of the outer equal-diameter section, at the end furthest from the inner stop, is the mounting section for the Y-shaped rubber sealing ring 7. The outer circumferential surface at the end furthest from the inner stop of the outer equal-diameter section is the threaded surface for mounting the threaded top ring 8.

[0042] The Y-shaped rubber seal is a high-low lip Y-shaped rubber seal for piston sealing.

[0043] The unloading ring 2 is a hollow rotating body. The unloading ring 2 and the mold body 1 are in a clearance fit. One end of the outer circumferential surface of the unloading ring has a radially protruding boss, which serves as the axial force-bearing boss when the spinning machine's material feeding mechanism acts axially on the unloading ring. The boss has a height of 20mm and an axial length of 15mm. The end face of this boss near the end of the unloading ring that is close to the workpiece is a sloped surface to prevent the spinning wheel from colliding with it; the taper of this sloped surface is 120°. Both inner ports of the unloading ring are flared. The sloped surface near the inner stop of the mold body has a taper of 145°, which fits with the 145° outer tapered section of the mold body, and has an axial length of 70mm. The sloped surface away from the inner stop of the mold body has an inner taper of 15° and an axial length of 15mm. The function of this tapered section is to allow the unloading ring to easily cross the sealing rings when unloading material axially along the mold body.

[0044] The threaded top ring 8 is a circular ring with a height of Lm. Its inner surface has an internal thread M that mates with and is fastened to the external thread section of the mold body 1. Its outer diameter is N, and six 10310 through grooves are evenly distributed circumferentially on its outer circumference. The function of this threaded top ring is to restrict the axial movement of the Y-shaped rubber sealing ring 7 after all the sealing rings are installed on the mold body 1.

[0045] The technical features of the present invention are illustrated in detail below through three embodiments.

[0046] Example 1

[0047] This embodiment is a spinning mandrel suitable for workpieces with an inner diameter of d4 = 250 ± 0.1 mm and a length of 2000 mm. It is used for the protection of the inner surface of the workpiece and the cleaning of oil during mass spinning.

[0048] The spinning mandrel includes a mold body 1, a stripper ring 2, a threaded top ring 8, and a sealing ring; the sealing ring includes a YX-type rubber sealing ring 3 for holes, a sealing ring without a retaining ring 6, and a Y-shaped rubber sealing ring 7. The Y-shaped rubber sealing ring is a high-low lip Y-shaped rubber sealing ring for piston sealing. Wherein:

[0049] The mold body 1 is a hollow rotating body with a long shaft shape. Its inner circumferential surface is divided into an inner conical section and an inner equal-diameter section. The taper of the inner conical section is 7.125° and the axial length is 120mm. The conical section is the inner stop of the mold body 1, which is used to assemble and position it with the machine tool spindle. In this embodiment, the diameter of the inner equal-diameter section of the mold body 1 is 166.7mm, which is 2 / 3 of the outer diameter, and is used to reduce the negative mass of the mold body.

[0050] The outer circumferential surface of the mold body 1 is divided into an outer cylindrical section, an outer conical section, an outer equal-diameter section, a Y-shaped rubber sealing ring mounting section, and an external thread section. The section near the inner stop is the outer cylindrical section of the mold body, with a diameter of Φ400mm and a length of 120mm, and is connected to the outer equal-diameter section via a 145° outer conical section. In this embodiment, the diameter D of the outer equal-diameter section is 249.7mm, and its length is 1600mm, which is 4 / 5 of the workpiece length. The end of the outer equal-diameter section, away from the inner stop, is the Y-shaped rubber sealing ring mounting section; the diameter d of this Y-shaped rubber sealing ring mounting section is 220mm, and its length is 20mm. The section away from the inner stop is the external thread section, with a length of 30mm.

[0051] The unloading ring 2 is a hollow rotating body, and the inner diameter of the unloading ring is... The axial length is 150mm, and the unloading ring 2 and the mold body 1 are clearance-fitted. One end of the outer circumferential surface of the unloading ring has a radially protruding boss, which is used to bear the axial force when the spinning machine's material feeding mechanism acts on the unloading ring axially. The boss is 20mm high and 15mm long axially. The end face of the boss near the end of the unloading ring that is close to the workpiece is a sloped surface to prevent the spinning wheel from colliding with it. The taper of this sloped surface is 120°. The inner ports at both ends of the unloading ring are flared. The taper of the sloped surface near the inner stop of the mold body is 145°, which fits with the 145° outer tapered section of the mold body, and the axial length is 70mm. The inner taper of the sloped surface away from the inner stop of the mold body is 15°, and the axial length is 15mm. The function of this tapered section is to allow the unloading ring to easily cross the sealing rings when unloading material along the axial direction of the mold body.

[0052] The threaded top ring 8 is a circular ring with a height of 30mm. Its inner surface is machined into an internal thread that fits and tightens with the external thread section of the mold body 1. The outer diameter is 247mm, and six 10310 through grooves are evenly distributed circumferentially on the outer circumferential surface. The function of this threaded top ring is to, after all the sealing rings are installed on the mold body 1, install the threaded top ring onto the external thread of the mold body 1 through its internal thread, thereby restricting the axial movement of the Y-shaped rubber sealing ring 7.

[0053] Two sealing ring grooves are machined on the outer circumferential surface of the equal-diameter section of the mold body. Specifically, a Yx-shaped sealing ring groove with an outer diameter of d4 = 250 mm is machined on the mold body 10 mm from the small end face of the unloading ring, along the direction away from the inner stop of the mold body. This Yx-shaped sealing ring groove conforms to standard JB / ZQ 4264-1997; the Yx-shaped sealing ring 3 conforms to standard JB / ZQ 4264-1997.

[0054] At a point 15mm away from the Y-shaped rubber sealing ring installation section, away from the end of the mold body's internal stop, a groove for a hydraulic seal without a retaining ring is machined along the direction of the stop. This groove conforms to standard GB / T 3452.3-1988, and hydraulic dynamic seals are preferred. The cross-sectional diameter of the retaining ring is d2 = 7.0mm, therefore the groove width is b = 9.5mm, and the groove depth is t = 5.85mm. The workpiece inner diameter corresponding to the groove size is d4 = 250 ± 0.1mm, and a groove diameter of d3 = 238.3mm is selected. This groove diameter should satisfy 0.25d2 ≤ d3 + 22d2 - d4 ≤ 0.45d2. Based on the groove size d4 = 250 ± 0.1mm, a retaining ring 6 with an inner diameter of d1 = 236mm and a cross-sectional diameter of d2 = 7.0mm is selected and installed. This retaining ring conforms to standard GB / T 3452.3-1988.

[0055] During installation, the Y-shaped rubber seal 7, the retaining ring-less seal 6, and the YX-type rubber seal 3 for the hole are sequentially installed on the mold body 1 from the Y-shaped rubber seal installation section towards the outer conical section of the mold body 1. When installing the retaining ring-less seal 6 and the YX-type rubber seal 3 for the hole, they need to be immersed in hydraulic oil at 60-70℃ and heated for 10-15 minutes before installation. After the Y-shaped rubber seal is installed on the Y-shaped rubber seal installation section of the mold body 1, the threaded top ring is installed on the external thread section of the mold body 1. By rotating the threaded top ring 8, its internal thread is locked to the external thread of the mold body 1 to restrict the axial movement of the Y-shaped rubber seal.

[0056] During use, the Yx-shaped sealing ring 3 for the hole effectively prevents metal debris from entering between the spun part and the mold along the high-flow-rate coolant, avoiding scratches on the surface of the spun part and the core mold. Therefore, the spun part has good appearance quality, uniform wall thickness, and a long service life of the core mold. At the same time, the pre-tightening effect of the Yx-shaped sealing ring 3 for the hole, which is squeezed and expanded, prevents the workpiece from being thrown out along the mold axis before spunting, and the workpiece is positioned. During the unloading process of the axially extended workpiece along the direction away from the stop of the mold, the hydraulic seal without a retaining ring 6 first strips the excess spun oil from the inner wall of the workpiece. Then, the piston seal with high and low lip Y-shaped rubber sealing ring 7 cleans the residual spun oil again. That is, the oil stains on the inner surface of the workpiece can be cleaned during the unloading and demolding process, which reduces the use of flammable and polluting organic solvents such as kerosene and reduces the generation of chemical waste. It is suitable for automated processing of mass products.

[0057] Example 2

[0058] This embodiment of the spinning mandrel is suitable for the protection and oil removal of the inner surface of workpieces with an inner diameter of d4 = 140 ± 0.1 mm and a length of 1800 mm during mass spinning processing. The spinning mandrel includes a mold body 1, a stripper ring 2, a threaded top ring 8, and sealing rings; the sealing rings include a YX-type rubber sealing ring 3 for holes, a sealing ring without a retaining ring 6, and a high-low lip Y-shaped rubber sealing ring 7 for piston sealing. Wherein:

[0059] The mold body 1 is a hollow rotating body with a long shaft shape. Its inner circumferential surface is divided into an inner conical section and an inner equal-diameter section. The taper of the inner conical section is 7.125° and the axial length is 120mm. The conical section is the inner stop of the mold body 1, which is used to assemble and position it with the machine tool spindle. In this embodiment, the inner diameter of the inner equal-diameter section of the mold body 1 is 70mm, which is half of the outer diameter, and is used to reduce the negative mass of the mold body.

[0060] The outer circumferential surface of the mold body 1 is divided into an outer cylindrical section, an outer conical section, an outer equal-diameter section, a Y-shaped rubber sealing ring mounting section, and an external thread section. The section near the inner stop is the outer cylindrical section of the mold body, with a diameter of Φ400mm and a length of 120mm. It is connected to the outer equal-diameter section via a 145° outer conical section. In this embodiment, the diameter D of the outer equal-diameter section is 139.7mm, and its length is 1200mm, which is 2 / 3 of the workpiece length. The end of this outer equal-diameter section, away from the inner stop, is the Y-shaped rubber sealing ring mounting section; the diameter of the Y-shaped rubber sealing ring mounting section is 120mm, and its length is 16mm. The section away from the inner stop of the Y-shaped rubber sealing ring mounting section is an M90 external thread section with a length of 30mm.

[0061] The unloading ring 2 is a hollow rotating body, and the inner diameter of the unloading ring is... The axial length is 150mm, and the unloading ring 2 and the mold body 1 are clearance-fitted. One end of the outer circumferential surface of the unloading ring has a radially protruding boss, which serves as the axial force-bearing boss when the spinning machine's material feeding mechanism acts axially on the unloading ring; the boss has a height of 20mm and an axial length of 10mm. The end face of the boss near the end of the unloading ring that is close to the workpiece is a sloping surface to prevent collision with the spinning wheel; the taper of this sloping surface is 120°. Both inner ports of the unloading ring are flared. The sloping surface near the inner stop of the mold body has a taper of 145°, fitting with the 145° outer tapered section of the mold body, and an axial length of 70mm; the sloping surface away from the inner stop of the mold body has an inner taper of 15° and an axial length of 10mm. Its function is to allow the unloading ring to easily cross the sealing rings when unloading material along the axial direction of the mold body.

[0062] The threaded top ring 8 is a circular ring with a height of 30mm. Its inner surface is machined into an internal thread that fits and tightens with the external thread section of the mold body 1. The outer diameter is 138mm, and six 10310 through grooves are evenly distributed circumferentially on the outer circumferential surface. The function of this threaded top ring is to, after all the sealing rings are installed on the mold body 1, install the threaded top ring onto the external thread of the mold body 1 through its internal thread, thereby restricting the axial movement of the Y-shaped rubber sealing ring 7.

[0063] Two sealing ring grooves are machined on the outer circumferential surface of the equal-diameter section of the mold body. Specifically, a Yx-shaped sealing ring groove with an outer diameter of d4 = 140 mm is machined on the mold body 10 mm from the small end face of the unloading ring, along the direction away from the inner stop of the mold body. This Yx-shaped sealing ring groove conforms to standard JB / ZQ 4264-1997; the Yx-shaped sealing ring 3 conforms to standard JB / ZQ 4264-1997.

[0064] At the end furthest from the stop of the mold body, 10mm from the installation section of the Y-shaped rubber sealing ring, a groove for a hydraulic sealing ring without a retaining ring is machined along the direction of the stop. This groove conforms to standard GB / T 3452.3-1988, and hydraulic dynamic seals are preferred. The cross-sectional diameter of the retaining ring is d2 = 5.3mm, therefore the groove width is b = 7.1mm, and the groove depth is t = 4.35mm. The workpiece inner diameter corresponding to the groove size is d4 = Φ140±0.1mm, and the selected groove diameter is d3 = 131.3mm. This groove diameter should satisfy 0.25d2≤d3+22d2-d4≤0.45d2. Based on the groove size d4 = Φ140±0.1mm, a retaining ring 6 with an inner diameter of d1 = Φ128mm and a cross-sectional diameter of d2 = 5.3mm is selected and installed. This retaining ring conforms to standard GB / T 3452.3-1988.

[0065] During installation, the mold body 1 is sequentially installed with a Y-shaped rubber seal 7, a retaining ring-less seal 6, and a YX-type rubber seal 3 for holes, starting from the Y-shaped rubber seal installation section and moving towards the outer conical section of the mold body 1. Specifically, the retaining ring-less seal 6 and the YX-type rubber seal 3 for holes are installed sequentially from the Y-shaped rubber seal installation section towards the outer conical section of the mold body 1. When installing the retaining ring-less seal 6 and the YX-type rubber seal 3 for holes, they must be immersed in hydraulic oil at 60-70°C and heated for 10-15 minutes before installation. After the Y-shaped rubber seal is installed on the Y-shaped rubber seal installation section of the mold body 1, the threaded top ring is installed on the external thread section of the mold body 1. By rotating the threaded top ring 8, its internal thread is locked to the external thread of the mold body 1, thus restricting the axial movement of the Y-shaped rubber seal.

[0066] During use, the Yx-shaped sealing ring 3 for the hole effectively prevents metal debris from entering between the spun part and the mold along the high-flow-rate coolant, avoiding scratches on the surface of the spun part and the core mold. Therefore, the spun part has good appearance quality, uniform wall thickness, and a long service life of the core mold. At the same time, the pre-tightening effect of the Yx-shaped sealing ring 3 for the hole, which is squeezed and expanded, prevents the workpiece from being thrown out along the axial direction of the mold before spunting, and the workpiece is positioned. During the unloading process of the axially extended workpiece along the direction away from the stop of the mold, the hydraulic seal without a retaining ring 6 first strips the excess spun oil from the inner wall of the workpiece. Then, the piston seal with high and low lip Y-shaped rubber sealing ring 7 cleans the residual spun oil again. That is, the oil stains on the inner surface of the workpiece can be cleaned during the unloading and demolding process, reducing the use of flammable and polluting organic solvents such as kerosene and reducing the generation of chemical waste. It is suitable for automated processing of mass products.

[0067] Example 3

[0068] This embodiment is a spinning mandrel suitable for workpieces with an inner diameter of d4 = 200 ± 0.1 mm and a length of 2400 mm. It is used for the protection of the inner surface of the workpiece and the cleaning of oil during mass spinning.

[0069] The spinning mandrel includes a mold body 1, a stripper ring 2, a threaded top ring 8, and a sealing ring; the sealing ring includes a YX-type rubber sealing ring 3 for holes, a sealing ring without a retaining ring 6, and a Y-shaped rubber sealing ring 7. The Y-shaped rubber sealing ring is a high-low lip Y-shaped rubber sealing ring for piston sealing. Wherein:

[0070] The mold body 1 is a hollow rotating body with a long shaft shape. Its inner circumferential surface is divided into an inner conical section and an inner equal-diameter section. The taper of the inner conical section is 7.125° and the axial length is 120mm. The conical section is the inner stop of the mold body 1, which is used to assemble and position it with the machine tool spindle. In this embodiment, the diameter of the inner equal-diameter section of the mold body 1 is 120mm, which is 3 / 5 of the outer diameter, and is used to reduce the negative mass of the mold body.

[0071] The outer circumferential surface of the mold body 1 is divided into an outer cylindrical section, an outer conical section, an outer equal-diameter section, a Y-shaped rubber sealing ring mounting section, and an external thread section. The section near the inner stop is the outer cylindrical section of the mold body, with a diameter of Φ400mm and a length of 120mm, and is connected to the outer equal-diameter section via a 145° outer conical section. In this embodiment, the diameter D of the outer equal-diameter section is 199.7mm, and its length is 1800mm, which is 3 / 4 of the workpiece length. The end of the outer equal-diameter section, away from the inner stop, is the Y-shaped rubber sealing ring mounting section; the diameter d of this Y-shaped rubber sealing ring mounting section is 178mm, and its length is 18mm. The Y-shaped rubber sealing ring mounting section, away from the inner stop, is the external thread section, with a length of 30mm.

[0072] The unloading ring 2 is a hollow rotating body, and the inner diameter of the unloading ring is... The axial length is 150mm, and the unloading ring 2 and the mold body 1 are clearance-fitted. One end of the outer circumferential surface of the unloading ring has a radially protruding boss, which is used to bear the axial force when the spinning machine's material feeding mechanism acts on the unloading ring axially. The boss is 20mm high and 15mm long axially. The end face of the boss near the end of the unloading ring that is close to the workpiece is a sloped surface to prevent the spinning wheel from colliding with it. The taper of this sloped surface is 120°. The inner ports at both ends of the unloading ring are flared. The taper of the sloped surface near the inner stop of the mold body is 145°, which fits with the 145° outer tapered section of the mold body, and the axial length is 70mm. The inner taper of the sloped surface away from the inner stop of the mold body is 15°, and the axial length is 15mm. The function of this tapered section is to allow the unloading ring to easily cross the sealing rings when unloading material along the axial direction of the mold body.

[0073] The threaded top ring 8 is a circular ring with a height of 30mm. Its inner surface is machined into an internal thread that fits and tightens with the external thread section of the mold body 1. The outer diameter is 196mm, and six 10310 through grooves are evenly distributed circumferentially on the outer circumferential surface. The function of this threaded top ring is to, after all the sealing rings are installed on the mold body 1, install the threaded top ring onto the external thread of the mold body 1 through its internal thread, thereby restricting the axial movement of the Y-shaped rubber sealing ring 7.

[0074] Two sealing ring grooves are machined on the outer circumferential surface of the equal-diameter section of the mold body. Specifically, a Yx-shaped sealing ring groove with an outer diameter of d4 = 200 mm is machined on the mold body 10 mm from the small end face of the unloading ring, along the direction away from the inner stop of the mold body. This Yx-shaped sealing ring groove conforms to standard JB / ZQ 4264-1997; the Yx-shaped sealing ring 3 conforms to standard JB / ZQ 4264-1997.

[0075] At a point 13mm from the Y-shaped rubber sealing ring installation section, away from the end of the mold body's internal stop, a groove for a hydraulic seal without a retaining ring is machined along the stop direction. This groove conforms to standard GB / T 3452.3-1988, and hydraulic dynamic seals are preferred. The cross-sectional diameter of the retaining ring is d2 = 5.3mm, therefore the groove width is b = 7.0mm, and the groove depth is t = 4.65mm. The workpiece inner diameter corresponding to the groove size is d4 = 200 ± 0.1mm, and a groove diameter of d3 = 191.5mm is selected. This groove diameter should satisfy 0.25d2 ≤ d3 + 22d2 - d4 ≤ 0.45d2. Based on the groove size d4 = 200 ± 0.1mm, a retaining ring 6 with an inner diameter of d1 = 188mm and a cross-sectional diameter of d2 = 5.3mm is selected and installed. This retaining ring conforms to standard GB / T 3452.3-1988.

[0076] During installation, the Y-shaped rubber seal 7, the retaining ring-less seal 6, and the YX-type rubber seal 3 for the hole are sequentially installed on the mold body 1 from the Y-shaped rubber seal installation section towards the outer conical section of the mold body 1. When installing the retaining ring-less seal 6 and the YX-type rubber seal 3 for the hole, they need to be immersed in hydraulic oil at 60-70℃ and heated for 10-15 minutes before installation. After the Y-shaped rubber seal is installed on the Y-shaped rubber seal installation section of the mold body 1, the threaded top ring is installed on the external thread section of the mold body 1. By rotating the threaded top ring 8, its internal thread is locked to the external thread of the mold body 1 to restrict the axial movement of the Y-shaped rubber seal.

[0077] During use, the Yx-shaped sealing ring 3 for the hole effectively prevents metal debris from entering between the spun part and the mold along the high-flow-rate coolant, avoiding scratches on the surface of the spun part and the core mold. Therefore, the spun part has good appearance quality, uniform wall thickness, and a long service life of the core mold. At the same time, the pre-tightening effect of the Yx-shaped sealing ring 3 for the hole, which is squeezed and expanded, prevents the workpiece from being thrown out along the mold axis before spunting, and the workpiece is positioned. During the unloading process of the axially extended workpiece along the direction away from the stop of the mold, the hydraulic seal without a retaining ring 6 first strips the excess spun oil from the inner wall of the workpiece. Then, the piston seal with high and low lip Y-shaped rubber sealing ring 7 cleans the residual spun oil again. That is, the oil stains on the inner surface of the workpiece can be cleaned during the unloading and demolding process, which reduces the use of flammable and polluting organic solvents such as kerosene and reduces the generation of chemical waste. It is suitable for automated processing of mass products.

Claims

1. A spinning mandrel with functions of workpiece inner surface protection and oil removal, characterized in that, The mold body (1), unloading ring (2), threaded top ring (8), and sealing rings are included. The sealing rings include YX-shaped rubber sealing rings (3), sealing rings without retainers (6), and Y-shaped rubber sealing rings (7). The outer circumferential surface of the mold body (1) is divided into an outer cylindrical section, an outer conical section, and an outer equal diameter section according to function. The large diameter end of the outer conical section is connected to the outer cylindrical section, and the small diameter end of the outer conical section is connected to one end of the outer equal diameter section. The other end of the outer equal diameter section has a two-stage stepped surface, which is the mounting surface of the Y-shaped rubber sealing ring and the external thread surface for mounting the threaded top ring. The unloading ring is fitted onto the outer circumferential surface of the mold body, and the inner inclined surface of one end of the unloading ring is in contact with the conical surface of the outer conical section of the mold body; the threaded top ring is installed on the external threaded surface at the end of the outer equal-diameter section of the mold body; the hole YX-shaped rubber sealing ring, the ringless sealing ring and the Y-shaped rubber sealing ring are sequentially placed on the outer circumferential surface of the outer equal-diameter section of the mold body, and the YX-shaped rubber sealing ring is located at the end face of the unloading ring; The inner circumferential surface of the mold body (1) is an inner conical section and an inner equal diameter section. The inner conical section has a taper of 7.125° and an axial length of 120mm. The inner conical section is the inner stop of the mold body and is used to assemble and position with the machine tool spindle. The inner diameter of the inner equal diameter section is 1 / 2 to 1 / 3 of the outer diameter. When in use, the YX-shaped rubber sealing ring effectively prevents metal debris from entering between the workpiece and the mold body; during the unloading process of the axially extended workpiece along the direction away from the inner stop of the mold body, the ringless sealing ring (6) first peels off the excess spinning oil on the inner wall of the workpiece, and then the Y-shaped rubber sealing ring (7) cleans the residual spinning oil again, that is, the oil stains on the inner surface of the workpiece can be cleaned during the unloading and demolding process.

2. The spinning mandrel with workpiece inner surface protection and oil cleaning functions as described in claim 1, characterized in that, The gap between the outer surface of the outer equal diameter section of the mold body (1) and the inner surface of the workpiece (5) is ≤0.7mm, and the length of the outer equal diameter section is 2 / 3 to 4 / 5 of the length of the workpiece.

3. The spinning die with workpiece inner surface protection and oil cleaning functions as described in claim 1, characterized in that, The distance between the adjacent surfaces of the ringless sealing ring (6) and the Y-shaped rubber sealing ring (7) is 10mm to 15mm.

4. The spinning die with workpiece inner surface protection and oil cleaning functions as described in claim 1, characterized in that, The retaining ring (6) and the YX-shaped rubber seal (3) for the hole are immersed in hydraulic oil at 60~70℃ for 10~15 minutes before installation.

5. The spinning mandrel with workpiece inner surface protection and oil cleaning functions as described in claim 1, characterized in that, The unloading ring (2) is a hollow rotating body; the unloading ring and the mold body (1) are in clearance fit; one end of the outer circumferential surface of the unloading ring has a radially protruding boss, which is used as an axial force boss when the spinning machine feeding mechanism acts on the unloading ring along the axial direction; the end face of the boss near the workpiece is an inclined surface to avoid collision between the spinning wheel and the workpiece, and the taper of the inclined surface is 120°; The inner ports at both ends of the unloading ring are flared openings.

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