JPH09250675A - Synthetic resin pipe joint with metallic connection member and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a pipe joint to which a connection member is connected solidly, in a synthetic resin pipe joint in which a metallic connection member to connect a metal pipe is insert-molded at one side, and a synthetic resin pipe is inserted and fused at the other side. SOLUTION: A metallic connection member 11 has a recessed groove form of notch 21 for stopping the rotation, as well as has recesses 17 and 18 in the pipe axial direction and in the direction orthogonal to the pipe axis, and after an adhesive modified polyethylene is applied to cover the metallic connection member, a cross-linked polyethylene is injection-molded. The removal and connection of the metallic connection member and a resin in the pipe axial direction, in the direction orthogonal to the pipe axis, and in the rotating direction are prevented by the recesses and the notch. After the formation, a core form of support metal fitting is inserted to the inside, and then heated by a heater so as to heat and fuse a modified polyethylene layer. And the polyethylene layer is pressure connected to the metallic connection member 11 solidly by the resin pressure generated by its expansion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joint, and more particularly to a synthetic resin pipe joint provided with a metal connecting member for connecting a metal pipe, and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, synthetic resin pipes excellent in lightness and flexibility have been widely used in the fields of water pipes, drainage pipes, gas pipes, etc., but metal pipes are also used in places where pressure resistance is required. The synthetic resin pipe and the metal pipe are used together. When a synthetic resin pipe and a metal pipe are used together, a pipe joint for connecting both pipes is required. Therefore, conventionally, such a pipe joint has a metal connecting member having an external screw or an internal screw connecting means on one side. There is a synthetic resin pipe joint with a metal connecting member that is insert-molded on the other side and inserts a synthetic resin pipe on the other side to fuse, but metal and synthetic resin are originally difficult to bond, and metal and synthetic resin Easy to peel off at the interface. Actual exploitation 57-483
No. 88 discloses a synthetic resin pipe having a modified polyolefin layer at the interface between the metal connecting member and the synthetic resin in order to improve the adhesion between the metallic connecting member of the synthetic resin pipe joint and the synthetic resin. A joint is disclosed.

[0003]

When the metal portion and the synthetic resin portion are bonded together via the modified polyolefin layer, the adhesiveness can be improved to some extent, but it is still not sufficient, and when external pressure such as bending or twisting is applied. The metal part and the synthetic resin part tend to be easily separated. An object of the present invention is to provide a synthetic resin pipe joint with a metal connecting member capable of preventing the metal connecting member from being separated from the synthetic resin, and a method for manufacturing the same.

[0004]

According to the present invention, therefore, a recess is provided in a metal connecting member of a synthetic resin pipe joint with a metal connecting member,
The resin portion that has entered the depression serves as a resistance to prevent the metal connecting member and the synthetic resin from being separated from each other, and is formed by insert molding a metal connecting member having a connecting means for mounting a metal pipe. In a synthetic resin pipe joint with a metal connecting member, in which a metal pipe is connected to one side and a synthetic resin pipe to the other side, the metal connecting member prevents the connecting member and the synthetic resin from being separated from each other. It is characterized in that it has a recess for making it.

The recess is formed in the tube axis direction to prevent the metal connecting member and the synthetic resin from being separated from each other in the direction orthogonal to the tube axis, that is, in the radial direction, or in the radial direction orthogonal to the tube axis. To prevent the metal connecting member and the synthetic resin from being separated from each other in the pipe axial direction, but preferably formed in the pipe axial direction and the radial direction orthogonal to the pipe axis to separate the pipe axial direction from the radial direction. Can be prevented.

In order to prevent the axial and radial disengagement,
The depression may be formed obliquely so that the depression has components in the tube axis direction and the radial direction. The above-mentioned depressions prevent the metallic connecting member and the synthetic resin from being separated from each other in the pipe axis direction and / or the radial direction orthogonal to the pipe axis. In addition to the above-mentioned depressions, it is desirable to provide irregularities, protrusions, hooks, etc. at the interface of the member with the synthetic resin so that the synthetic resin can be intricately incorporated.

[0007] In order to prevent disengagement in the rotation direction due to twisting, the metal connecting member is preferably provided with a recess and a protrusion and other rotation stopping means together with the depression. As described above in the metal connecting member, it is effective to provide the depression or the rotation stopping means to prevent the metal connecting member and the synthetic resin from being separated from each other. This will impair the smooth flow of resin during injection molding. In particular, when holes are provided in the metal connecting member as shown in FIG. 8 to prevent rotation, welds cause delamination in the synthetic resin layer or cracks in the resin layer as shown in the figure. It was found that this tends to cause fluid leakage.

As a result of various experiments to solve this problem, the present inventors have found that some of the plurality of corners of the metal connecting member at the interface between the metal connecting member and the synthetic resin are preferable. If the whole is chamfered or the rotation stopping means is made into a concave groove-shaped notch, the smooth flow of the resin will not be impaired, welds and delamination will not occur, and cracks will occur in the notch. Also found that it can be avoided.

Another invention was made based on this finding, in which the metal connecting member is provided with a recess or a rotation stopping means together with the recess, and in each of the synthetic resin pipe joints described above, the metal connecting member and the synthetic resin are provided. A part, preferably all, of a plurality of corners of the metal connecting member at the interface with and are chamfered, and still another invention is the above in which the recess and the rotation stopping means are provided in the metal connecting member. In the above synthetic resin pipe joint, the rotation stopping means is a groove-shaped notch.

Still another preferred invention is a combination of the above inventions. In the above-mentioned synthetic resin pipe joint in which a recess and a rotation stopping means are provided in the metallic connecting member, the metallic connecting member and the synthetic resin are provided. It is characterized in that a part or all of a plurality of corners of the metal connecting member at the interface with and are chamfered, and the rotation stopping means is a groove-shaped notch.

In each of the above inventions, in order to improve the adhesion between the metal connecting member and the synthetic resin, a modified polyolefin layer is formed at the interface between the metal connecting member and the synthetic resin,
Alternatively, it is desirable to mix the modified polyolefin with the synthetic resin. Another invention for achieving the above object is to insert-mold a metal connecting member having a connecting means for mounting a metal pipe, and then heat the interface between the metal connecting member and the synthetic resin to a temperature not lower than the softening point of the synthetic resin. Is characterized by.

According to the experiments conducted by the present inventors, it has been found that heating the interface between the metal connecting member and the synthetic resin above the softening point of the synthetic resin enables the metal connecting member and the synthetic resin to be firmly bonded. It was It is considered that this is because the resin pressure increases due to the volume expansion of the interface resin when it is heated and melted, and the pressure bonding with the connection member progresses. In order to improve the adhesiveness between the metal connecting member and the synthetic resin, a metal, ceramic, or wooden support is fitted into the synthetic resin portion that is bonded to the connecting member from inside or outside or inside and outside, and the support is attached to the resin portion. It is desirable that the resin be heated or melted while being brought into close contact or being pressed to the resin portion. When the interfacial resin expands in volume, the expansion of the resin portion is restricted by the support, so that the resin is more strongly pressure-bonded to the connecting portion.

In order to improve the adhesion between the metal connecting member and the synthetic resin, a modified polyolefin layer may be provided at the interface between the metal connecting member and the synthetic resin, as described above.
Alternatively, it is desirable to mix the modified polyolefin into the injected synthetic resin. A synthetic resin pipe fitting with a metal connecting member provided with a modified polyolefin layer can be obtained by setting a metal connecting member coated with modified polyolefin in a mold and performing insert molding, and modifying the metal connecting member. In order to coat the polyolefin, various conventionally known methods, for example, a method in which a modified polyolefin is heat-fused by an electrostatic coating method or a fluid immersion method, a modified polyolefin film is heat-fused or a metal connecting member is used. A method of heating and fusing, a method of immersing in a modified polyolefin solution or an emulsion and then drying, and the like can be adopted. When coating the modified polyolefin, the surface of the metal connecting member is washed with a strong acidic aqueous solution, a strong alkaline aqueous solution, a detergent or the like in advance,
It is desirable to carry out the primer treatment with an adhesion modifier such as alkoxytitanium after or without washing, for example. As a result, stronger adhesiveness can be obtained. The modified polyolefin coated on the metal connecting member is preferably heat-treated in the presence of alcohol. This makes it possible to suppress the deterioration of the adhesive force between the metal portion and the resin portion with time. Examples of the alcohol used here include aliphatic alcohols such as isobutyl alcohol and dihydric alcohols such as ethylene glycol. Among these, ethylene glycol is preferable. The heat treatment performed by bringing the modified polyolefin coated on the metal connecting member into contact with alcohol is usually performed at about 200 ° C. for 30 minutes to several hours.

The thickness of the modified polyolefin coating applied to the metallic connecting member is usually 1 to 10 ⁴ μm, preferably 5 to 5 × 10 ² μm. Examples of the modified polyolefin include acrylic acid, unsaturated carboxylic acids such as maleic acid, unsaturated carboxylic acid anhydrides such as maleic anhydride, amides of unsaturated carboxylic acids, and modified monomers such as unsaturated epoxides such as glycidyl methacrylate. Examples thereof include at least one modified by graft copolymerization.

The content of the modified monomer component in the modified polyolefin is 0.001 to the modified polyolefin.
It is preferably in the range of 5% by weight. As the modified polyolefin, it is also possible to employ a composition obtained by blending an unmodified polyolefin with a polyolefin obtained by modifying all of the polyolefin with the above-mentioned modifying monomer. On the other hand, a synthetic resin pipe fitting with a metal connecting member mixed with a modified polyolefin can be obtained by setting a metal connecting member in a mold and injection molding a mixture of the modified polyolefin in a synthetic resin. it can.

The temperature at which the interface between the metal connecting member and the synthetic resin is heated is preferably a temperature at which at least a part of the synthetic resin melts, and is usually in the range of 120 ° C to 350 ° C. If the heating temperature is lower than this range, the effect will be weakened, and if the heating temperature is higher than this range, the resin will be thermally deteriorated and the adhesive strength will be reduced. The heating time varies depending on the size of the pipe joint and is not particularly limited, but if it is too short, the melting of the resin is incomplete, and if it is too long, the productivity is poor and the resin is deteriorated.
It is preferably in the range of 20 to 100 seconds.

The interface resin can be heated by, for example, heating a metal connecting member with a heater, heating the metal connecting member with electromagnetic waves such as ultrasonic waves or microwaves, and heating the metal connecting member at a high temperature. It is convenient and desirable to heat only the metallic connecting member by immersing it in an oil bath and heating it, but the entire pipe joint may be heated again in the mold after insert molding. Also, the resin pressure may be increased during insert molding so that the injection time is set longer than the normal molding time so that the molten state is maintained by applying the injection pressure even after the molten resin is filled in the mold. .

Therefore, in this method, insert molding is performed for a longer time than usual molding, and the interface between the metal connecting member and the synthetic resin is maintained at a temperature equal to or higher than the softening point of the resin even after the mold is filled with the resin. It In each of the above inventions, examples of the metal material used for the metal connecting member include iron, copper, aluminum and alloys thereof, but there is no particular limitation.

As the connecting means for attaching the metal pipe, for example, screws, welding, union nuts, etc. can be exemplified. The synthetic resin used for the pipe joint of each of the above inventions is not particularly limited as long as it is a thermoplastic resin. Examples thereof include polyolefins such as polyethylene, polypropylene, polybutene-1, cross-linked polyethylene, polyvinyl chloride, polyester, polyamide, polyacetal and the like.

The method of the present invention is applied to a synthetic resin pipe joint for connecting a metal pipe and a synthetic resin pipe, but can also be applied to a synthetic resin pipe joint for connecting metal pipes. .

[0021]

1 shows an example of a synthetic resin pipe joint 12 in which a metal connecting member 11 is insert-molded, the pipe joint body is made of cross-linked polyethylene, and one side is a heating wire (illustrated). It is a so-called electrofusion joint in which a polyethylene pipe 13 is inserted, and then the heating wire is energized for a certain period of time to perform heat fusion bonding.

The metal connecting member 11 has an external screw 15 as a connecting means for attaching a metal pipe (not shown), and a contact portion with the crosslinked polyethylene 16 has a structure shown in FIG.
As shown in Fig. 1, the metallic connecting member 11 and the cross-linked polyethylene 1
A recess 17 is formed in the pipe axis direction in order to prevent 6 from being disengaged in the radial direction orthogonal to the pipe axis, and at the same time, prevents the metallic connecting member 11 and the crosslinked polyethylene 16 from being disengaged in the pipe axial direction. Therefore, a dent 18 in the radial direction orthogonal to the tube axis is formed, and a projection 19 and a recess 20 are provided to ensure that the metal connecting member 11 is prevented from coming off. The metal connecting member 11 further has a recessed groove-shaped notch 21 which is shallower than the end face in the pipe axis direction to prevent rotation.

Insert molding of the metal connecting member 11 is performed by
After the primer is applied to the metallic connecting member, it is dipped in an adhesive modified polyolefin solution to be coated with the modified polyolefin, then set in a mold and cross-linked polyethylene is injection-molded. As a result, as shown in FIG.
3. The crosslinked polyethylene layer 16 is formed via the adhesive modified polyolefin layer 24.

Next, as shown in FIG. 4, the synthetic resin pipe fitting with the metal connecting member is screwed into the heater 28 with the core-shaped support metal fitting 27 fitted inside,
The heater 28 heats the metallic connecting member 11 to heat and melt the modified polyolefin layer 24 (not shown in FIG. 4) between the connecting member 11 and the crosslinked polyethylene 16. As a result, the modified polyolefin layer 24 thermally expands and is pressed against the metal connecting member 11 by the resin pressure.

FIG. 5 shows a union joint type synthetic resin pipe joint with a metallic connecting member. The metallic connecting member 31 provided with a collar 31a has an inner screw 33 similar to the metallic connecting member 11 described above. It is insert-molded with the union nut 32 that it has, and has a recess 35 in the radial direction orthogonal to the pipe axis at the contact portion with the cross-linked polyethylene 34, and also has a groove-shaped notch 36 for stopping rotation. , The corners of the interface in contact with the cross-linked polyethylene are all chamfered. By screwing the union nut 32 into a union screw fixed to a metal pipe (not shown), the metal pipe is connected to the metallic connecting member 31, and the union screw and the union nut 32 are connected to each other by a connecting means. Are configured. In the figure, 30 is an o-ring for sealing which is interposed between the metal pipe and the metal connecting member 31.

FIG. 6 shows another example of a synthetic resin pipe joint with a metal connecting member, and an inner screw 3 as a connecting means.
The metal connection member 39 having 8 is insert-molded in the same manner as the metal connection member 11 described above, and in the connection portion with the crosslinked polyethylene 40, a radial recess 41 orthogonal to the pipe axis and a pipe axis direction. Has a recess 42 and a notch 43 in the shape of a groove for stopping rotation, and all corners contacting the cross-linked polyethylene are chamfered.

In each of the above embodiments, a synthetic resin pipe joint for connecting a polyethylene pipe and a metal pipe is shown, but in another embodiment, connecting members are insert-molded on both sides of the joint body to form a metal pipe. Comrades are connected.

[0028]

【Example】

Example 1 After the surface of the brass connecting member 45 having the structure shown in FIG. 7 was titanated to form a titanium oxide film,
A powder of adhesive modified polyolefin (trade name "Admer") manufactured by Mitsui Petrochemical Industry Co., Ltd. was coated on a brass connecting member by a fluidized dipping method. Next, steam of ethylene glycol was brought into contact with this and heat-treated at 200 ° C. for 1 hour, then set in a mold and cross-linked polyethylene was injection-molded to obtain a synthetic resin pipe joint shown in FIG. 7. When the inside and outside of the obtained synthetic resin pipe joint were visually inspected, no welds, delamination, cracks or the like were found.

Next, the following cold water hammer test was conducted on this synthetic resin pipe joint. Cold water at 7 ° C. was flown for 3.5 minutes, and a water hammer of 17.5 kg / cm ² was added repeatedly for 2 seconds and 3 times. Next, warm water at 85 ° C. was poured for 2.5 minutes, and the same water hammer was applied the same number of times (3 times). A total of 6 with such cold and hot water
The cold water hammer test for 1 minute was set as one cycle, and this was repeated for 100,000 cycles or more, but no water leakage was observed.

Example 2 The synthetic resin pipe fitting with a metal connecting member shown in FIG. 7 obtained by the method of Example 1 was heated for 60 seconds at a heater temperature of 320 ° C. using the heater 28 shown in FIG. After 60 seconds, it was removed from the heater 28 and immersed in water at 20 ° C. for cooling. Regarding the synthetic resin pipe joint with the metal connecting member that has been heat-treated by the heater 28 as described above, the metal connecting member 45
A notch was made at the interface between the resin and the resin with a knife, and the metal connecting member was grasped with pliers to peel it off, but it could not be peeled off.

Comparative Example 1 A metal having the same structure as the metal connecting member 45 shown in FIG. 7 except that a hole 47 is formed in a radial recess 48 orthogonal to the tube axis instead of the notch 46 in FIG. Using the connecting member 48, insert molding was performed by the same method as in Example 1, and FIG.
A synthetic resin pipe joint with a metal connecting member as shown in was obtained.

Next, as a result of the same cold water hammer test as in Example 1, as a result, water leakage occurred after reaching 5000 cycles. When the inside and outside of the synthetic resin pipe joint at this time were visually inspected, welds were formed and delamination occurred, and cracks as shown in the figure occurred in the joint inner surface resin layer. Comparative Example 2 The peeling test of the metallic connecting member 45 was performed by the same method as in Example 2 without heating the synthetic resin pipe joint with the metallic connecting member shown in FIG. 7 obtained by the method of Example 1 with a heater. As a result, the metallic connecting member was peeled off with a slight force.

[0033]

In the pipe joint made of synthetic resin with a metal connecting member according to the first aspect of the present invention, by providing a recess in the metal connecting portion, the resin that enters the recess by insert molding becomes a resistance and becomes a metal. It is possible to prevent the manufactured connecting member and the synthetic resin from being separated from each other.

When the recess is formed in the pipe axis direction as in the second aspect of the invention, it is possible to prevent the metallic connecting member and the synthetic resin from being separated from each other in the radial direction orthogonal to the pipe axis. When the depression is formed in the radial direction as in the invention described above, it is possible to prevent the metallic connecting member and the synthetic resin from being separated from each other in the axial direction of the pipe. Further, when the recess is formed in the pipe axis direction and in the radial direction orthogonal to the pipe axis or obliquely as in the invention according to claim 4 or 5, the direction of the pipe axis and the radial direction is different from each other. However, it is possible to prevent the metallic connecting member and the synthetic resin from being separated from each other. When the contact surface with the synthetic resin has a complicated shape as in the sixth aspect of the present invention, the separation of the both can be prevented more reliably.

If the corners are chamfered as in the seventh aspect of the invention, the resin flow during injection molding becomes smooth,
It becomes difficult to form a weld. When the rotation preventing means is provided on the metal connecting member as in the invention of claim 8, it is possible to prevent the metal connecting member and the synthetic resin from being separated from each other in the rotation direction. If the anti-rotation means is a groove-shaped cutout, the smooth flow of the resin during injection molding is not impaired, and the weld and delamination due to the cutout,
It is possible to prevent the occurrence of cracks and the like.

When the modified polyolefin layer is provided between the metallic connecting member and the synthetic resin as in the tenth aspect of the present invention, the adhesive force between the metallic connecting member and the synthetic resin can be increased. When heat is applied after molding as in the invention described in claim 11, the resin is pressure-bonded to the metal connecting member, and the metal connecting member can be firmly adhered.

According to the twelfth or thirteenth aspect of the present invention, the metallic connecting member is coated with the modified polyolefin and injection-molded, or when the modified polyolefin is mixed in the synthetic resin and injection-molded. And the adhesiveness with the synthetic resin can be further improved. Claim 14
According to the invention described above, since the expansion of the resin is regulated by the support, the resin is more firmly pressed against the metal connecting member.

According to the invention described in claims 15 to 17, only the metallic connecting member can be heated easily. According to the eighteenth aspect of the present invention, it is possible to efficiently perform heating using a molding machine without separately providing a heating unit or a heating step. According to the invention described in claim 19, it is possible to prevent the metallic connecting member and the synthetic resin from being separated from each other in the axial direction and the radial direction and / or in the rotational direction.

According to the twentieth or twenty-first aspect of the invention, the metal connecting member can be bonded more firmly. According to the invention of claim 22, deterioration with time of the adhesive force between the metal portion and the resin portion is suppressed.

[Brief description of drawings]

FIG. 1 is a front view of a synthetic resin pipe joint with a metal connecting member.

FIG. 2 is a sectional view of an essential part of a synthetic resin pipe joint with a metal connecting member according to the present invention.

FIG. 3 is an enlarged cross-sectional view in which a primer layer and a modified polyolefin layer are interposed between a metal connecting member and crosslinked polyethylene.

FIG. 4 is a cross-sectional view showing a method of heating a synthetic resin pipe joint with a metal connecting member by a heater.

FIG. 5 is a sectional view of a union type synthetic resin pipe joint with a metal connecting member.

FIG. 6 is a sectional view showing another example of a synthetic resin pipe joint with a metal connecting member.

FIG. 7 is a cross-sectional view of a synthetic resin pipe joint with a metal connecting member according to an embodiment.

FIG. 8 is a cross-sectional view of a synthetic resin pipe joint with a metal connecting member according to a comparative example.

[Explanation of symbols]

11, 31, 39, 45 ··· Metal connecting member 12 · · Synthetic resin pipe joint 13 · · Polyethylene pipe 15 · · Outer screw 16, 34, 40 · · Cross-linked polyethylene 17, 18, 35, 41, 42, 48 ・ ・ Dimples 19 ・ ・ Protrusions 20 ・ ・ Recesses 21, 36, 43, 46 ・ ・ Notches 23 ・ ・ Primer layer 24 ・ ・ Modified polyolefin layer 27 ・ ・ Support metal fittings 28 ・ ・ Heater 30 ・ ・ o
Ring 32 · Union nut 33, 38
..Inner screw 47..hole

Claims (22)

[Claims] 1. A molded product obtained by insert-molding a metal connecting member having a connecting means for mounting a metal pipe, wherein a metal pipe is connected to one side and a synthetic resin pipe is connected to the other side. In synthetic resin pipe fittings with connection members,
A synthetic resin pipe joint with a metal connection member, characterized in that a recess is formed in the metal connection member to prevent the connection member and the synthetic resin from being separated from each other. 2. The recess is formed in the tube axis direction.
A synthetic resin pipe fitting with the described metal connecting member. 3. The synthetic resin pipe joint with a metal connecting member according to claim 1, wherein the recess is formed in a radial direction orthogonal to the pipe axis. 4. The synthetic resin pipe joint with a metal connecting member according to claim 1, wherein the recess is formed in a pipe axis direction and a radial direction orthogonal to the pipe axis. 5. The synthetic resin pipe joint with a metal connecting member according to claim 1, wherein the recess is formed obliquely. 6. The synthetic resin with a metallic connecting member according to claim 1, wherein the metallic connecting member has a contact interface with the synthetic resin having a complicated shape such as irregularities, protrusions, and hooks. Pipe fittings. 7. The method according to any one of claims 1 to 6, wherein at least a part of a plurality of corners of the metal connecting member at the interface between the metal connecting member and the synthetic resin is chamfered. Synthetic resin pipe fitting with metal connecting member. 8. The metal connecting member according to claim 1, wherein the metal connecting member is provided with rotation preventing means for preventing the metal connecting member and the synthetic resin from being rotationally separated from each other. A synthetic resin pipe fitting with a connecting member. 9. The synthetic resin pipe joint with a metal connecting member according to claim 8, wherein the rotation stopping means is a groove-shaped notch. 10. A synthetic resin pipe joint with a metal connecting member according to claim 1, wherein a modified polyolefin layer is provided between the metal connecting member and the synthetic resin. 11. A method for manufacturing a synthetic resin pipe joint with a metal connecting member, which is obtained by insert molding a metal connecting member having a connecting means for mounting a metal pipe, after the insert molding, a metal connecting member is provided. A method for producing a synthetic resin pipe joint with a metal connecting member, characterized in that the interface of the synthetic resin is heated to a temperature not lower than the softening point of the synthetic resin. 12. The method for producing a synthetic resin pipe joint with a metal connecting member according to claim 11, wherein the metal connecting member coated with the modified polyolefin is insert-molded. 13. The method for producing a synthetic resin pipe joint with a metal connecting member according to claim 11, wherein the modified polyolefin is mixed in the synthetic resin injected by insert molding. 14. The synthetic resin pipe joint with a metal connecting member according to claim 11, wherein the heating is performed with the support fitted in the synthetic resin portion from the inside and / or the outside. Production method. 15. The method for manufacturing a synthetic resin pipe joint with a metal connecting member according to claim 11, wherein the heating is performed by bringing a heater into contact with the metal connecting member. 16. The method for producing a synthetic resin pipe joint with a metal connecting member according to claim 11, wherein heating is performed by applying electromagnetic waves such as ultrasonic waves or microwaves to the metal connecting member. 17. A method for producing a synthetic resin pipe joint with a metal connecting member, wherein heating is performed by immersing the metal connecting member in a high temperature oil bath. 18. A metal connecting member having a connecting means for mounting a metal pipe is insert-molded, and an interface where the metal connecting member and the synthetic resin are in contact is a modified polyolefin layer, or in a synthetic resin to be injected. In a method for producing a synthetic resin pipe joint containing a modified polyolefin, a method for producing a synthetic resin pipe joint with a metal connecting member, characterized in that, during insert molding, injection pressure is continuously applied even after the resin is filled in the mold. . 19. The method for manufacturing a synthetic resin pipe joint with a metal connecting member according to claim 11, wherein the metal connecting member is provided with a recess and / or a rotation stopper. 20. The synthetic resin pipe joint with a metal connecting member according to claim 12, wherein the metal connecting member is coated with the modified polyolefin after previously cleaning the metal surface with a strong acid aqueous solution, a strong alkaline aqueous solution or a detergent. Manufacturing method. 21. The synthetic resin pipe joint with a metal connecting member according to claim 12, wherein the modified polyolefin is coated on the metal connecting member after the metal connecting member is primed with an adhesion modifier or the like. Production method. 22. The modified polyolefin coated on the metallic connecting member is heat treated in the presence of alcohol.
The method for producing a synthetic resin pipe joint with a metal connecting member according to claim 0, 12, 18, 20, or 21.