JPS6245049B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a pipe joint having a large bend such as a bent made of reinforced resin.
Conventionally, when manufacturing pipe joints with bent parts made of reinforced resin, if a core mold with a curved central part and sockets at both ends was used, the core mold could not be demolded. , as disclosed in Japanese Utility Model Application Publication No. 51-48629, a split mold in which the objects on the large arc curved surface side and the small arc curved surface side are equally divided along the axis, and a socket part connected to both ends of the split mold. A reinforced resin molding material is supplied to a mold made of a short forming cylinder to form a molding material layer,
A molding method is known in which the mold is divided and demolded after curing.

However, when trying to rotate the above-mentioned mold and wind the reinforced resin molding material on it, the mold has a heavy short cylinder for forming a socket part connected to the end of the curved split mold. It is necessary to rotate a mold that is unbalanced with respect to the rotation axis, which requires a large amount of power and sturdy equipment, and the equipment becomes expensive.Also, the mold may run out of center and the molding material cannot be wound properly on top of it. The disadvantage was that it was difficult to wind the winding work.

The present invention has been made for the purpose of solving the above-mentioned conventional drawbacks and manufacturing reinforced resin pipe joints by a winding molding method. Wrap the reinforced resin molding material around the surface so that it becomes thinner toward the tip of the end.
After hardening, the mold is demolded to form a bent member, and one thin end of the bent member is attached to one end of a core mold for molding a socket part, which is cantilever-supported on a rotating shaft with the other end unsupported. After mounting and fixing, a reinforced resin molding material is wound from the outer peripheral surface of the core mold for molding the socket to the outer peripheral surface of the end of the bending member, and after hardening, the mold is removed to form a socket at the end of the bending member. A method of manufacturing a reinforced resin pipe joint is provided.

EMBODIMENT OF THE INVENTION Hereinafter, one Example of the manufacturing method of the bend type reinforced resin pipe joint of this invention is demonstrated with reference to drawings.

FIG. 1 is a vertical cross-sectional view explaining the first half of the process in an embodiment of the present invention, FIG. 2 is a vertical cross-sectional view explaining the second half of the process in an embodiment of the present invention, and FIG. FIG. 2 is a longitudinal cross-sectional view showing a pipe joint manufactured according to an example.

Reference numeral 1 is a core mold for forming a bent part, in which cylinders 11 and 11' bent in an arc shape in the axial direction are connected at the center, and flanges 12 and 1 are provided at the ends of the cylinders 11 and 11'.
2' is provided, and a disc 1 is attached to the flanges 12, 12'.
3 and 13' are connected, and rotating shafts 14 and 14' are provided on the sides of the discs 13 and 13'. The core mold 1 for forming bent portions is placed on a stand (not shown in the drawings) so as to be rotatable around rotating shafts 14, 14', and one of the rotating shafts 14, 14' is connected to a rotary drive device (not shown in the drawings). connected.

The core mold 1 for forming the curved portion is driven by a rotary drive device, and a mat made of glass fiber or the like impregnated with a resin liquid made of unsaturated polyester resin or the like mixed with an appropriate hardening agent is wrapped around it. A surface layer 201 is formed, and a reinforcing layer 202 is formed by wrapping a blind cloth made of glass fiber or the like so that the direction of the reinforcing fibers is in the axial direction, and then the resin liquid is applied to long fibers such as glass roving. The impregnated material is wound to form a reinforcing layer 203 in the circumferential direction, and finally, short fibers such as glass fibers are sprinkled on the surface of the molding layer at both ends to embed some of the short fibers into the molding layer. A layer 204 with an exposed portion is formed, and the bent member 2 is formed by appropriately heating and curing in a heating furnace or the like.
When winding each layer, the ends of the bending member 2 are made to become thinner toward the tip. For example, the inner surface layer 201 is wound up to the end of the core mold 1, but the reinforcing layers 202 and 203 may be made thin in steps without being wound all the way to the end, or each layer may be made gradually thinner toward the tip of the end. You can also wrap it so that

In addition, the outer surface of both ends of the bending member 2 may be sanded to partially expose the fibers after curing without scattering the short fibers.

Next, the core mold 1 for forming the bent portion is removed from the frame, the disks 13 and 13' are removed from the cylinders 11 and 11', and the central parts of the cylinders 11 and 11' are uncoupled. , 11' are demolded and the bending member 2 is taken out. Reference numeral 3 denotes a socket molding die having a portion with an outer surface shape that matches the inner surface shape of the socket to be molded, and a collar 34 is provided on the outside of one end of the large diameter portion 31, and a boss portion is provided on the inside. 35, the other end is gradually made smaller in diameter, and a small diameter portion 32 having an outer diameter approximately equal to the inner diameter of the end of the bending member 2 is provided at the tip thereof, and an annular groove 33 is provided on the outer peripheral surface of the small diameter portion 32. A hollow annular body 3 made of an elastic body is inserted into the annular groove 33.
6 is installed, and a boss portion 321 is installed inside the small diameter portion 32.
A rotary shaft 37 is inserted through and fixed to the boss portions 35 and 321. Also, the hollow annular body 36
The hollow part is communicated with a through hole provided in the rotating shaft 37, and can be pressurized from the outside.

The socket mold 3 has a rotating shaft 37 supported in a cantilever manner on a frame not shown in the drawings, and is rotatable by a drive device not shown in the drawings.

One thin end 21 of the bending member 2 is fitted into the small diameter portion 32 of the socket mold 3 with the other end 22 unsupported, and air is pressurized into the hollow annular body 36.
The annular body 36 is expanded to fix the bending member 2 to the socket mold 3.

The socket mold 3 was rotated, and an appropriate curing agent was mixed with unsaturated polyester resin in a mat made of glass fiber or the like from the outer peripheral surface of the socket mold 3 to the outer peripheral surface of one end 21 of the bending member 2. The inner layer 41 is formed by impregnating a resin liquid and wrapping the inner layer 41, and then winding a blind cloth made of glass fiber or the like impregnated with the resin liquid so that the direction of the reinforcing fibers is in the axial direction to form an axial reinforcing layer. A reinforcing layer 43 in the circumferential direction is formed by winding long fibers such as glass rovinge impregnated with the resin liquid thereon, and after hardening by heating in a heating furnace or the like, the annular body 36 is pressurized. is released and removed from the socket mold 3 to form a socket part 4 at one end of the bent member 2.

A socket portion 4' is also formed on the other end 22 of the bending member 2 using the same means as described above, and the molding of the pipe joint is completed.

As mentioned above, in the manufacturing method of the reinforced resin pipe joint of the present invention, the forming of the bending member and the forming of the socket part on the end of the bending member are performed in separate steps using a winding method, so each The core mold used in the process can be simplified, and as if the two were integrated, there is no need for large-scale equipment that uses large amounts of power to rotate the mold, which is heavy and significantly unbalanced with respect to the rotation axis. The core mold can be rotated smoothly, the winding method has high work efficiency, and the strength in the circumferential direction is large and the shape accuracy is good. First, the bent member is formed, and then the end of the bent member is A mouth part can be formed, and one end of the bending member is attached and fixed to one end of a core mold for molding the socket part, which is cantilever-supported on the rotating shaft with the other end unsupported. Even if the molding of the bent member and the molding of the socket on the end of the bent member are performed in separate processes, the bent member with the large bend formed in the previous process is placed in the core mold for molding the socket. It is possible to quickly and reliably attach and fix it to one end and move on to the next receptacle molding process.

In addition, in the present invention, the bending member is formed so as to become thinner toward the tip of the end, and a reinforced resin molding material is wound around the outer peripheral surface of this end and hardened to form the socket. The end of the bent member and the socket are made thin at the tip of the joint, and when an external bending force is applied to the bent pipe, the thin wall deforms and relieves stress, causing peeling at the joint. You get what you don't have to do. Furthermore, by reducing the thickness of the joint, a socket with a clean outer surface can be formed.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view illustrating the first half of the process in an embodiment of the present invention, FIG. 2 is a longitudinal sectional front view illustrating the latter half of the process in an embodiment of the present invention, and FIG. FIG. 2 is a longitudinal sectional front view of a pipe joint manufactured according to an example. Explanation of the symbols: 1... Core mold for forming the bent part, 2... Bent member, 3... Mold for forming the socket part.

Claims (1)

[Claims] 1. Wrap the reinforced resin molding material around the outer circumferential surface of the core mold for forming the bent part so that it becomes thinner toward the tip of the end.
After hardening, the mold is demolded to form a bent member, and one thin end of the bent member is attached to one end of a core mold for molding a socket part, which is cantilever-supported on a rotating shaft with the other end unsupported. After mounting and fixing, a reinforced resin molding material is wound from the outer peripheral surface of the core mold for molding the socket to the outer peripheral surface of the end of the bending member, and after hardening, the mold is removed to form a socket at the end of the bending member. A method for manufacturing a reinforced resin pipe joint, characterized by: