Coil combination foaming auxiliary tool and foaming process thereof

Abstract

The coil combination foaming auxiliary tool comprises a large framework and a coil wound on the large framework, the auxiliary tool comprises an expansion shaft tool, an expansion sleeve and a foaming mold, the expansion shaft tool is sleeved with the expansion sleeve, the front portion of the expansion shaft tool and the expansion sleeve extend into an inner cavity of the large framework, the expansion shaft tool can open the expansion sleeve, and the foaming mold is arranged on the expansion shaft tool. The foaming mold is arranged outside the coil, and a foaming material is poured into the foaming mold. Due to the fact that the expansion shaft tool and the expansion sleeve are used in cooperation to support the inner cavity of the large framework, the inner cavity of the large framework is evenly expanded, all parts of the inner cavity of the large framework are evenly stressed, the phenomena of deformation and swelling of the inner cavity of the large framework caused by high temperature and expansion generated in the foaming process are prevented, the consistency of all sizes of the inner cavity of the large framework before and after foaming is guaranteed, and the foaming quality is improved. The one-time success rate of product assembly is increased to 100% from original 10%, the qualified rate of coil combination foaming is greatly improved, the foaming bottleneck is solved, and the purpose of batch production is finally achieved.

Description

Technical Field

[0001] The invention relates to the technical field of aerospace device assembly auxiliary tools, and in particular to a wire package combined foaming auxiliary tooling and a foaming process thereof. Background Art

[0002] The development and production of space launch devices is one of the key projects of the aerospace factory and an important component for the factory to independently produce new products. In the development process of the launch device, since the foaming process has an important influence on the electrical properties of the wire package combination, the wire package combination foaming process technology of the cylindrical component is the focus of the research and development work. The foaming method currently used is chemical foaming, which uses chemical methods to generate gas to foam plastic. This method uses isocyanate, polyether, amino ether, alkali-free glass fiber and quartz sand for mixing and stirring, and uses the gas released by chemical reactions between the plastic components to foam. Similar to the general injection molding process, the heating, mixing, plasticization and most of the foaming and expansion of the plastic are completed in the injection molding machine. Therefore, no matter what kind of plastic raw material, the foaming process generally goes through the stages of forming bubble nuclei, bubble nucleus expansion, and foam body solidification.

[0003] The wire package assembly is a hollow cylindrical structure made of nylon material, including a large frame, coils, wire harnesses, etc. During the foaming process of the wire package assembly, the material and structure of the wire package assembly are easily affected by thermal expansion and contraction, and the materials required for foaming will generate high temperature and pressure during the chemical reaction process, which makes it possible for the foaming material in the existing wire package assembly cover to be evenly distributed in various parts, which can easily lead to problems such as uneven density of the foaming material in the wire package assembly and insufficient strength of certain parts after foaming. The pressure generated by foaming is uneven, and the high temperature, expansion and extrusion will cause uneven force on the inner cavity of the large frame, resulting in deformation and bulging. The consistency of various dimensions of the inner cavity of the large frame before and after foaming is poor, resulting in a 90% scrap rate and a very low success rate in the early stage of launch device development.

[0004] At the same time, since the filling operation of the wire package combination foaming is performed manually, and the foaming material has a fast chemical reaction and a short curing time, inaccurate process steps may result in the foaming material completing the chemical reaction and curing before the filling is completed, resulting in foaming failure. The natural chemical reaction of the foaming material may also cause the foaming material to expand, overflow and solidify, resulting in the foaming material in the wire package combination cover being unable to evenly cover the entire cover cavity, causing the pressure in the cavity to be inconsistent and causing the cavity to deform, resulting in waste.

[0005] According to the deformation of the inner cavity of the large frame of the wire package combination, 5 large frames after foaming were tested. The test results are shown in Table 1 below:

[0006] It can be seen that under the existing foaming process, the test results are all unqualified. Since the wire package assembly foaming is a one-time product assembly, if bulging or deformation occurs in the inner cavity of the large frame, the product cannot be repaired, resulting in unqualified products, which will cause serious losses to the factory and affect the development progress. The foaming problem has long been the focus and difficulty of the development of the launch device. It is a bottleneck in the future transition stage and needs to be solved as soon as possible. Summary of the invention

[0007] The purpose of the present invention is to provide a wire package combined foaming auxiliary tooling and a foaming process thereof which can keep the inner cavity of a large frame from bulging and deformation and has a high foaming success rate, so as to overcome the shortcomings of the above-mentioned prior art.

[0008] The technical solution adopted by the present invention is: a wire package combination foaming auxiliary tooling, the wire package combination includes a large frame and a wire package wound on the large frame, the auxiliary tooling includes an expansion shaft tooling, an expansion sleeve and a foaming mold, the expansion sleeve is sleeved on the outside of the expansion shaft tooling, the front part of the expansion shaft tooling and the expansion sleeve extend into the inner cavity of the large frame, the expansion shaft tooling can expand the expansion sleeve and tighten the large frame at the starting point of the wire package, the foaming mold is arranged outside the wire package, and the foaming material is poured into the foaming mold.

[0009] A further technical solution is: the expansion shaft tooling comprises an expansion shaft, a pressure rod, a hand wheel, a sleeve, a clamping rod, a pressure block, a cone block I, a connecting rod and a cone block II; The expansion shaft is a multi-petal hollow cylindrical structure, the front end of the pressure rod is engaged with the rear end of the clamping rod, the clamping rod is a sleeve structure, the front end of which extends into the expansion shaft and is connected to the connecting rod, the other end of the connecting rod is connected to the cone block II, the connecting rod and the cone block II are both arranged in the expansion shaft, the hand wheel is sleeved outside the pressure rod and is threadedly connected to the pressure rod, the front end of the hand wheel is connected to the sleeve, the sleeve is sleeved outside the pressure rod and the clamping rod, the front end of the hand wheel extends into the expansion shaft, the pressure block and the cone block I are arranged between the front end of the sleeve, the clamping rod and the expansion shaft, the inner hollow of the expansion shaft matches the shape of its internal parts, and during foaming, the expansion sleeve is sleeved outside the expansion shaft.

[0010] Further: a plurality of slits are evenly arranged on the expansion sleeve, and circular holes are opened at the roots of the slits to form a concave step shape, and the expansion sleeve is thin at the front and thick at the back.

[0011] Further: the foaming mold includes a left half mold, a right half mold and an upper mold. The left half mold and the right half mold are connected and sleeved outside the wire package. The upper mold is sleeved on the large frame and connected to the left half mold and the right half mold. A sealing port is provided on the left half mold.

[0012] Furthermore: the expansion shaft is provided with an external clamp.

[0013] Furthermore: a gasket is arranged between the pressing block and the cone block I.

[0014] Furthermore: the hand wheel and the sleeve are connected and fixed by pin I, and the connecting rod and the cone block II are connected and fixed by pin II.

[0015] Another related technical solution is: a method for foaming using the wire package combined foaming auxiliary tooling described in any one of the above technical solutions, and the specific steps are: (1) Prepare the foaming materials and the necessary instruments and equipment, and operate in a dedicated foaming room. The foaming materials are JB-1 type rigid polyester foam plastic A, B and C materials, and the instruments and equipment are electronic scales and high temperature boxes; (2) Put the expansion sleeve into the expansion shaft tooling, put it into the corresponding position of the starting wire package in the inner cavity of the large frame, rotate the hand wheel, and the expansion shaft and expansion sleeve will expand and tighten the inner cavity of the large frame and fix it; (3) Take 13g~15g of JB-1 rigid polyester foam material A and 3g~4g of C, pour into a beaker, and stir evenly in a clockwise direction; (4) Pour 16g to 19g of material B into the beaker containing material A and material C, and stir the foaming material clockwise for 30s to 50s. (5) Quickly and evenly inject the prepared foaming material into the foaming mold of the wire package assembly within 4 to 6 seconds, plug the grouting hole with a screw plug, and let it stand for 3 to 5 minutes; (6) Place the wire package assembly injected with foaming material into a 50±5℃ high temperature test box and set the temperature to 45℃~55℃; (7) After keeping warm for 1 to 3 hours, take it out and cool it to room temperature, remove the screw plug, and use a blade to clean the foaming flash of the wire package assembly; (8) Remove the expansion shaft tooling, expansion sleeve and foaming mold; (9) Foaming is completed.

[0016] Due to the adoption of the above technical solution, the wire package combined foaming auxiliary tooling and the foaming process thereof of the present invention have the following beneficial effects: 1. Since the present invention uses an expansion shaft tooling and an expansion sleeve to support the inner cavity of the large frame, the inner cavity of the large frame is evenly expanded and tightened, the expansion sleeve is in full contact with the inner cavity of the large frame, tightly fitted without gaps, and the various parts of the inner cavity of the large frame are evenly stressed, preventing the high temperature and expansion generated during the foaming process from causing deformation and bulging of the inner cavity of the large frame, ensuring the consistency of the dimensions of the inner cavity of the large frame before and after foaming, and thus the auxiliary foaming products meet the requirements of various indicators after testing, and the product assembly success rate has increased from the original 10% to 100%, which greatly improves the qualified rate of wire package assembly foaming, solves the bottleneck of foaming, and finally achieves the purpose of batch production; 2. The foaming process of the present invention is used for foaming, which effectively avoids the foaming material from expanding and overflowing due to natural chemical reaction or completing chemical reaction and solidification before potting is completed, thus protecting the wire package well and further improving the qualified rate of foamed products; 3. Since the expansion sleeve of the present invention is provided with multiple gaps, when the expansion shaft tooling expands and tightens the expansion sleeve, the expansion sleeve can fit tightly to the inner cavity of the large frame, ensuring that the inner cavity of the large frame is evenly stressed under the high temperature and pressure generated by the foaming material, and will not bulge or deform. At the same time, a circular hole is provided at the root of the gap, which can effectively prevent the root of the gap of the expansion sleeve from breaking when expanding, and also increases the elasticity of the expanded arc, so that the contact surface of the arc and the large frame can fit tightly; 4. Since the present invention is provided with a left half mold, a right half mold and an upper mold for filling the foaming material, for mold opening and injection molding, and fixed molding, not only the stability and consistency of each product are improved, but also the product can be reused, the cost is reduced, and it is economical and practical.

[0017] The technical features of the wire package combined foaming auxiliary tooling and its foaming process of the present invention are further explained below in conjunction with the drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the assembly process of the wire package combined foaming auxiliary tooling of the present invention; Figure 2 This is a schematic diagram of the structure of the wire package combined foaming auxiliary tooling assembly of the present invention; Figure 3 for Figure 2 Side view; Figure 4 This is a schematic diagram of the expansion shaft tooling structure of the present invention; Figure 5 This is a schematic diagram of the expansion shaft structure of the present invention; Figure 6 for Figure 5 Side view; Figure 7 It is a schematic diagram of the compression rod structure of the present invention; Figure 8-Figure 9 This is a schematic diagram of the hand wheel structure of the present invention; Fig.10 It is a schematic diagram of the sleeve structure of the present invention; Fig.11 It is a schematic diagram of the structure of the pressing rod of the present invention; Figure 12-13 It is a schematic diagram of the connecting rod structure of the present invention; Fig.14 This is a schematic diagram of the structure of cone block I of the present invention; Fig.15 This is a schematic diagram of the structure of cone block II of the present invention; Fig.16 It is a schematic diagram of the briquetting structure of the present invention; Fig.17 It is a schematic diagram of the gasket structure of the present invention; Fig.18 It is a schematic diagram of the clamp structure of the present invention; Fig.19 It is a schematic diagram of the expansion sleeve structure of the present invention.

[0019] In the figure: 1—expansion shaft fixture, 101—pressure rod, 102—hand wheel, 103—pin Ⅰ, 104—sleeve, 105—pressing rod, 106—pressure block, 107—cone block Ⅰ, 108—expansion shaft, 109—connecting rod, 110—pin Ⅱ, 111—cone block Ⅱ, 112—clamp, 113—gasket; 2—expansion sleeve, 21—round hole, 22—slit; 3—line package combination, 31—line package, 32—large frame; 4—foaming mold, 41—screw plug, 42—potting port, 43—left half mold, 44—upper mold, 45—right half mold, 46—fixing screw. DETAILED DESCRIPTION

[0020] Embodiment 1

[0021] A wire package combined foaming auxiliary tooling, such as Figures 1 to 3 As shown, the wire package combination 3 includes a large frame 32 and a wire package 31 wound on the large frame, and the auxiliary tooling includes an expansion shaft tooling 1, an expansion sleeve 2 and a foaming mold 4. The expansion sleeve 2 is sleeved on the outside of the expansion shaft tooling 1, and the front part of the expansion shaft tooling 1 and the expansion sleeve 2 extend into the inner cavity of the large frame 32. The expansion shaft tooling 1 can expand the expansion sleeve 2 and tighten the large frame 32 to start the wire package. The foaming mold 4 is arranged outside the wire package 31, and the foaming material is poured into the foaming mold 4.

[0022] like Figures 4 to 18As shown, the expansion shaft fixture 1 includes an expansion shaft 108, a pressure rod 101, a hand wheel 102, a sleeve 104, a clamping rod 105, a pressure block 106, a cone block I 107, a connecting rod 109 and a cone block II 111; the expansion shaft 108 is a six-petal hollow cylindrical structure, the pressure rod 101 is a screw-shaped rod, a trapezoidal notch is provided at the front end of the pressure rod 101 and is engaged with a trapezoidal notch at the rear end of the clamping rod 105, the clamping rod 105 is a sleeve structure, the rear rod sleeves the front rod, the rear rod can be telescoped back and forth relative to the front rod, the clamping rod 105 extends into the expansion shaft 108, the front rod of the clamping rod is connected to the connecting rod 109, the other end of the connecting rod 109 is connected to the cone block II 111 through a pin II 110, the connecting rod 109 and the cone block II 111 They are all arranged in the expansion shaft 108, the handwheel 102 is sleeved outside the pressure rod 101 and is threadedly connected to the pressure rod 101, the front end of the handwheel 102 is connected to the sleeve 104 through the pin Ⅰ103, the sleeve 104 is sleeved outside the pressure rod 101 and the clamping rod 105, and the front end extends into the expansion shaft 108, the front end of the sleeve 104 is connected to the pressure block 106, the front end of the pressure block 106 is provided with a gasket 113 and a cone block Ⅰ107, the pressure block 106 and the cone block Ⅰ107 are arranged between the clamping rod 105 and the expansion shaft 108 and sleeved on the clamping rod 105, the inner hollow of the expansion shaft 108 is consistent with the shape of the conical shape of the cone block, the columnar shape of the pressure block and other internal components, the expansion shaft 108 is provided with a clamp 112, and when foaming, the expansion sleeve 2 is sleeved outside the expansion shaft 108.

[0023] like Fig.19 As shown, the expansion sleeve 2 is made of 45# steel, heat-treated with HRC28-32, and six gaps 22 with a length of 94mm and a width of 1mm are evenly arranged on the expansion sleeve 2, that is, a gap is opened at every 60 degrees, so that after the expansion shaft expands the expansion sleeve, the expansion sleeve can fit tightly against the inner cavity of the large frame, ensuring that the inner cavity of the large frame is evenly stressed under the high temperature and pressure generated by the foaming material, and no bulging or deformation will occur; a φ6 circular hole 21 is opened at the root of the gap 22 to form a concave step, which can effectively prevent the root of the expansion sleeve gap from breaking when expanding, and at the same time increase the elasticity of the expanded arc, so that the contact surface of the arc and the large frame can fit closely; the expansion sleeve 2 is thin at the front and thick at the back, that is, the thickness is reduced by 1.5mm at the front end of the expansion sleeve 25mm long, so that the expansion sleeve gives way to the position of the inner retaining ring of the large frame after being placed in the inner cavity of the large frame.

[0024] like Figure 2 As shown, the foaming mold 4 includes a left half mold 43, a right half mold 45 and an upper mold 44. The left half mold 43 and the right half mold 45 are connected and sleeved on the outside of the wire package 31 by fixing screws 46. The upper mold 44 is sleeved on the large frame 32 and connected to the left half mold 43 and the right half mold 45. A sealing port 42 is provided on the left half mold 43, and a screw plug 41 is provided at the sealing port 42. When in use, the foaming material is injected from the sealing port 42 to solidify the foaming material in the foaming mold 4 to form a tissue structure that protects the wire package 31.

[0025] The principle of using the expansion shaft: keep the pressure rod 101 fixed, rotate the hand wheel 102, drive the pressure block 106 through the sleeve 104, and make the pressure block 106 move axially relative to the clamping rod 105, forcing the cone block I 107 to approach the cone block II 111. The cone block I 107 expands the multi-petal structure of the expansion shaft 108 radially through the cone structure, thereby expanding the expansion sleeve 2 until the expansion sleeve 2 fits tightly into the inner cavity of the large frame cylinder to achieve the expansion effect.

[0026] Due to the use of expansion shaft tooling and expansion sleeves, the combined effect of the expansion of the expansion shaft tooling and the uniform distribution of the expansion force by the expansion sleeve can effectively resist bulging and deformation caused by the high temperature and expansion generated during the foaming process of the foaming material, thereby foaming out qualified products. The design of the expansion shaft tooling and expansion sleeves plays a key role in maintaining the inner cavity of the large frame invariant deformation, solving the bottleneck of foaming.

[0027] After using the wire package combined foaming auxiliary tooling of the present invention, the deformation of 5 large frames after foaming was tested, and the test results are shown in Table 2 below:

[0028] From the comparison of Table 1 and Table 2, it can be seen that after using the wire package combined foaming auxiliary tooling of the present invention, there is no bulging or deformation in the inner cavity of the large frame, the inner diameter size meets the technical requirements, and relevant tests were carried out after the test. The insulation resistance and electrical properties all meet the technical requirements, and the foaming effect is good.

[0029] Embodiment 2

[0030] A wire package combined foaming process, which is a method of foaming using the wire package combined foaming auxiliary tooling described in Example 1, and the specific steps are: (1) Prepare the foaming materials and the necessary instruments and equipment, and operate in a dedicated foaming room according to the following process foaming method. The foaming materials are JB-1 type rigid polyester foam plastic A material, B material and C material, and the instruments and equipment are electronic scales and high temperature boxes; (2) Put the expansion sleeve into the expansion shaft tooling, put it into the corresponding position of the starting wire package in the inner cavity of the large frame, rotate the hand wheel, the expansion shaft expands, the expansion sleeve is stretched and tightened to tighten the inner cavity of the large frame and fix it; (3) After all preparations are completed, pour the foaming materials JB-1 rigid polyester foam plastic A and C into the beaker at a weight ratio of 14g and 3.5g, and stir evenly in a clockwise direction; (4) Pour 16g, 17.5g or 19g of material B into the beaker containing material A and material C, and stir the foaming material clockwise for 30s, 40s or 50s with a stirrer; (5) Quickly and evenly inject the prepared foaming material into the foaming mold of the wire package assembly within 4, 5 or 6 seconds, plug the grouting hole with a screw plug, and let it stand for 3 to 5 minutes; (6) Place the wire package assembly that has been injected with foaming material (without removing the expansion shaft) into a 50±5℃ high temperature test chamber and set the temperature to 55℃, which is the optimal temperature for the wire package assembly to foam and can effectively promote the chemical reaction between the foaming materials; (7) After keeping warm for 1h, 2h or 3h, take it out and cool it to room temperature, remove the screw plug, and use a blade to clean the foaming flash of the wire package assembly; (8) Remove the expansion shaft tooling, expansion sleeve and foaming mold; (9) Foaming is completed.

[0031] The above-mentioned wire package combined foaming process is used for foaming, and the following indicators can be achieved after foaming: ① Hardness: 60-70 (HD Shaw); ② Density: 45-60kg / m³; ③ Water absorption rate: less than 0.075 kg / m²; ④ Flame retardant value: 2S; ⑤ Compressive strength: greater than 200Mpa, which meets the electrical and insulation properties of the components and improves the foaming qualification rate.

[0032] The above embodiments are only preferred embodiments of the present invention. The structure and method of the present invention are not limited to the forms listed in the above embodiments. Any modifications, equivalent substitutions, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A wire package assembly foaming auxiliary tool, the wire package assembly (3) comprising a large frame (32) and a wire package (31) wound around the large frame, characterized in that: The auxiliary tooling comprises an expansion shaft tooling (1), an expansion sleeve (2) and a foaming mold (4); the expansion sleeve (2) is sleeved outside the expansion shaft tooling (1); the front part of the expansion shaft tooling (1) and the expansion sleeve (2) extend into the inner cavity of the large frame (32); the expansion shaft tooling (1) can expand the expansion sleeve (2) and expand the large frame (32) at the starting point of the winding package; the foaming mold (4) is arranged outside the winding package (31); and the foaming material is poured into the foaming mold (4).

2. The wire package combined foaming auxiliary tooling according to claim 1 is characterized in that: The expansion shaft tooling (1) comprises an expansion shaft (108), a pressure rod (101), a hand wheel (102), a sleeve (104), a clamping rod (105), a pressure block (106), a cone block I (107), a connecting rod (109) and a cone block II (111); The expansion shaft (108) is a multi-petal hollow cylindrical structure. The front end of the pressure rod (101) is engaged with the rear end of the clamping rod (105). The clamping rod (105) is a sleeve structure. The front end of the pressure rod (101) extends into the expansion shaft (108) and is connected to the connecting rod (109). The other end of the connecting rod (109) is connected to the cone block II (111). The connecting rod (109) and the cone block II (111) are both arranged in the expansion shaft (108). The hand wheel (102) is sleeved outside the pressure rod (101) and is connected to the pressure rod. (101) is threadedly connected, the front end of the hand wheel (102) is connected to the sleeve (104), the sleeve (104) is sleeved outside the pressure rod (101) and the clamping rod (105), and the front end extends into the expansion shaft (108), and a pressure block (106) and a cone block I (107) are arranged between the front end of the sleeve (104), the clamping rod (105) and the expansion shaft (108), and the inner hollow of the expansion shaft (108) matches the shape of its inner parts. When foaming, the expansion sleeve (2) is sleeved outside the expansion shaft (108).

3. The wire package combined foaming auxiliary tooling according to claim 1 is characterized in that: A plurality of slits (22) are evenly arranged on the expansion sleeve (2), and a circular hole (21) is provided at the root of the slit (22) to form a concave step shape. The expansion sleeve (2) is thin at the front and thick at the back.

4. The wire package combined foaming auxiliary tooling according to claim 1 is characterized in that: The foaming mold (4) comprises a left half mold (43), a right half mold (45) and an upper mold (44); the left half mold (43) and the right half mold (45) are connected and sleeved outside the wire package (31); the upper mold (44) is sleeved on the large frame (32) and connected to the left half mold (43) and the right half mold (45); and a potting port (42) is provided on the left half mold (43).

5. The wire package combined foaming auxiliary tooling according to claim 2 is characterized in that: The expansion shaft (108) is provided with a clamp (112) externally.

6. The wire package combined foaming auxiliary tooling according to claim 2 is characterized in that: A gasket (113) is provided between the pressing block (106) and the cone block I (107).

7. The wire package combined foaming auxiliary tooling according to claim 2 is characterized in that: The hand wheel (102) and the sleeve (104) are connected and fixed via a pin I (103), and the connecting rod (109) and the cone block II (111) are connected and fixed via a pin II (110).

8. A wire package combined foaming process, characterized in that: It is a method for foaming using the wire package combined foaming auxiliary tooling described in any one of claims 1 to 7, and its specific steps are: (1) Prepare the foaming materials and the necessary instruments and equipment, and operate in a dedicated foaming room. The foaming materials are JB-1 type rigid polyester foam plastic A, B and C materials, and the instruments and equipment are electronic scales and high temperature boxes; (2) Put the expansion sleeve into the expansion shaft tooling, put it into the corresponding position of the starting wire package in the inner cavity of the large frame, rotate the hand wheel, and the expansion shaft and expansion sleeve will expand and tighten the inner cavity of the large frame and fix it; (3) Take 13g~15g of JB-1 rigid polyester foam material A and 3g~4g of C, pour into a beaker, and stir evenly in a clockwise direction; (4) Pour 16g to 19g of material B into the beaker containing material A and material C, and stir the foaming material clockwise for 30s to 50s. (5) Quickly and evenly inject the prepared foaming material into the foaming mold of the wire package assembly within 4 to 6 seconds, plug the grouting hole with a screw plug, and let it stand for 3 to 5 minutes; (6) Place the wire package assembly injected with foaming material into a 50±5℃ high temperature test box and set the temperature to 45℃~55℃; (7) After keeping warm for 1 to 3 hours, take it out and cool it to room temperature, remove the screw plug, and use a blade to clean the foaming flash of the wire package assembly; (8) Remove the expansion shaft tooling, expansion sleeve and foaming mold; (9) Foaming is completed.

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