JPS5951410B2 - Continuous manufacturing equipment for synthetic resin pipes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to continuous manufacturing in which tubes are continuously formed using synthetic resin materials and tube forming materials containing synthetic resin materials.
A series of synthetic resin tubes with a means for actively cooling the core forming member and/or the bare inner surface of the molded tube at the tip inside the core so that the molded tube leaving the core mold has sufficient self-retention strength. This relates to manufacturing equipment.

In continuous molding of synthetic resin pipes, tube forming materials such as fiber aggregates impregnated with thermosetting resin material or granules containing thermosetting resin material are wound around a rotating core die, and during the process A tube is formed by winding reinforcing fibers or other tube forming materials, and these forming materials are cured in a thermosetting furnace while being wound around a core mold, and the hardened tube is removed from the core mold. A method of continuously manufacturing resin pipes by extrusion-like mold release is well known.

For example, as shown in FIG. 1, a method for producing reinforced synthetic resin pipes using a Drostholm machine has a hollow shaft 2 fixed almost horizontally in a machine drive device 1. The hollow rotating shaft 3 is freely supported, and at the same time, the hollow rotating shaft 3 is actively rotationally driven within the machine drive unit 1. On the other hand, a mandrel frame 4 is fixed to the hollow rotating shaft 3 via a support frame 18, and the mandrel frame 4 is formed by a large number of bars fixed to the support frame 18 in parallel with the mandrel direction. The surface is constructed by forming a suitable abutment surface or by providing rollers so that an endless steel belt 7, which will be described later, can be wound thereon and placed horizontally thereon. The endless steel belt 7 is spirally wound around the mandrel frame 4, and the belt 7 is guided into the offshore fixed shaft 2 at the tip of the mandrel frame 4, advances in the direction of the arrow, reaches the winding start position again, and then wraps around the mandrel. It is wrapped around the frame 4. That is, the mandrel frame 4 is connected to the machine driving device 1.
The belt 7 is rotated actively at , and the belt 7 is wound around the mandrel 4 while maintaining a specific tension. At the winding start position of the belt 7, a sliding member 5 that pushes the wound belt 7 toward the tip of the mandrel frame 4 is slidably provided at the end of the mandrel frame 4, and the sliding member 5 is always in operation. It is biased and supported by a spring or the like so as to protrude toward the platform driving device 1 side. Further, a cam 6 is fixed to the drive device 1 on the belt-wrapping side of the mandrel frame 4, and the sliding member 5 has its biasing protruding end connected to the cam 6.
The sliding member 5 contacts the surface of the mandrel frame 4 and rotates together with the mandrel frame 4, and along with this rotation, the sliding member 5 slides on the mandrel frame 4 in the direction of the mandrel frame. On the other hand, the other end of the sliding member 5 on the mandrel frame side is configured to abut against the edge of the wound belt 7. Therefore, the wound belt 7 is pushed in the distal direction along the mandrel frame 4 by the sliding member 5 as the mandrel frame 4 rotates, and the amount of belt pushing movement of the sliding member 5 is equal to 1 of the mandrel frame 4. It is the width of the belt 7 per rotation. Therefore, the core mold is formed by an endless steel belt 7 tightly wound spirally around the outer periphery of the rotating mandrel frame 4, and this steel belt 7 circulates to form the core mold.
Various resin pipes are continuously molded using such core molds,
The pipe manufacturing method illustrated in Figure 1 is an example of a composite pipe, in which the pipe forming material differs depending on the purpose or type of pipe, or it is composed of multiple layers like a composite pipe. A releasing cellophane tape 8 is wrapped around the outer periphery of the tape, and then a nonwoven fabric 9 impregnated with a thermosetting resin, such as an unsaturated polyester resin, is wrapped around the outer circumference of the tape, and a glass fiber strip also soaked in the thermosetting resin is used as a reinforcing material. If necessary, longitudinal reinforcing fibers are added to the glass fiber strip 10 to form a tube layer, and a resin mortar 11 is wound as an intermediate layer. The resin mortar 11 is mixed with a mixing device 12. The mixture is kneaded, extruded, and wound spirally through a suitable guide. Then, a resin-impregnated nonwoven fabric or the like may be wrapped again around the outer periphery of this resin mortar layer, but in the illustrated example, the glass fiber strip 13 is wrapped again in the same manner as in 10 above, and the resin-impregnated non-woven fabric 14 or the like is again wrapped as a finishing outer layer. is wound. The tube-forming material wound around the outer circumference of the core mold in this way is sequentially moved to the tip of the core mold as the belt 7 moves, and is led to a heating furnace 15 arranged so as to surround the core mold, where it is hardened. Reinforced resin pipe 1
6 is molded. Then, the belt 7 forming the core mold is unwound from the mandrel frame 4 at a position past the heating furnace 15, and circulates through the hollow fixed shaft 2 as described above. Further, the molded tube 16 is cut to an appropriate length, and the release tape 8 is appropriately wound. However, in order to increase production in continuous molding of resin pipes, it is necessary to increase the rotation speed of the mandrel and the temperature of the heating furnace, but the temperature of the heating furnace depends on the type of resin material. Therefore, there are restrictions, and for example, with the unsaturated polyester resin, when the temperature exceeds 140° C., the styrene in the polyester evaporates, causing problems such as swelling of the inner surface of the tube or formation of small cracks. Therefore, only a relatively low temperature can be designed, and instead it is necessary to increase the heating area of the heating furnace 15. However, if these improvements were to be made, it would be necessary to lengthen the mandrel frame 4 and also replace the belt 7, which would require a great deal of expense. Therefore, the inventor of the present invention has arrived at the present invention as a result of intensive study to increase production using conventional equipment.In other words, the outer layer of the resin pipe that exits the conventional heating furnace is not sufficiently hardened. However, in some cases, sufficient curing did not proceed in the inner layer, particularly in the part where the belt 7 was removed, and the shape retention strength of the tube was not sufficient after being separated from the belt 7.

However, it is said that the temperature at the detached part of the molded tube can reach as high as 100℃, but in general, the yield strength of reinforced synthetic resin pipes is 2 to 3 when the temperature is lowered from 100℃ to 70℃.
It is also known that the improvement can be doubled. Therefore, the inventor of the present invention actively blows cold air onto the belt and/or the inner surface of the tube just before the formed tube 16 leaves the core metal, thereby increasing the temperature of the inner surface of the tube to 20°C.
The present invention has been completed by focusing on improving the yield strength of the pipe inner layer by lowering the temperature by about 50°C. The present invention will be explained below based on the drawings, but the drawings show specific examples of the device of the present invention, and the present invention is not limited to the device shown in the drawings. It can be used or implemented by changing the design.

FIG. 2 is a schematic central sectional view of the core type illustrated in FIG. 1 with the belt 7 and drive section omitted, and a gear 17 is fixed to the offshore rotary shaft 3 and driven. FIG. 3 is a cross-sectional view of the core mold illustrated in FIG. 2 to which the present invention is applied, and FIG. 4 is a cross-sectional view taken along cutting line IV--IV in FIG. 3 in the direction of the arrow. In these figures, 19 indicates a fumarole drum, and the fumarole drum 19
is composed of a peripheral wall and both side walls, and the both side walls are fixed to the hollow rotating shaft 3 or are fixed by forming a flange part to the hollow rotating shaft 3.
provided at the tip of the Although the figure shows that a part of the tip of the hollow rotating shaft 3 is constituted by a fume drum 19, the fume drum 19 may be fitted and attached to the hollow rotating shaft 3. Therefore, fumarole holes 20 are bored in the peripheral wall surface of the fumarole drum 19,
A blowhole 24 is bored only in the tip measurement side wall 23 of both side walls. On the other hand, a hole 22 communicating with the fume drum 19 is bored in the hollow fixed shaft 2 corresponding to the fume drum 19 installation part of the hollow rotary shaft 3, so that cold air is sent to the fume drum 19 via the hollow fixed shaft 2. Configure. 21, 21 are cold air introduction ports.

However, the hollow fixed shaft 2 is constructed to allow the passage of a steel belt 7, but the belt 7 is formed of a thin piece, and a cold air sealing device is provided at each of the belt guide port and the outlet of the hollow fixed shaft 2. 5 and 6 illustrate a sealing device on the belt inlet side, and FIGS. 7 and 8 illustrate a sealing device on the outlet side. That is, the inlet side sealing device 25
A beak-shaped guide member 27 is attached to be fitted onto the hollow fixed shaft 2, and a belt passage {L28 is provided at the tip of the guide member 27. The guide member 27 is divided into two pieces and molded from an elastic material such as synthetic rubber or resin. On the other hand, the exit side sealing device 26 has a beak-shaped guide member 31 similar to that provided on the inlet side.
is enclosed in a split mounting ring 29 and attached to the hollow fixed shaft 2. 31 is a belt passage hole.

Note that although an elastic beak-like member is used for these seals, other sealing devices such as labyrinth means may be used for sealing. In this way, the continuous production apparatus for synthetic resin pipes of the present invention blows cold air at the tip of the mandrel and near the part where the belt 7 separates from the inner surface of the tube, and onto the back surface of the belt 7 and/or the inner surface of the tube from which the belt 7 has separated. This makes it possible to cool the inner layer of the pipe wall as much as possible to promote hardening and maintain sufficient strength to maintain the shape of the inner layer of the pipe wall after it has separated from the core mold, thereby increasing the tube forming speed. Moreover, there is no fear of deformation, contributing to improved quality and increased production.

[Brief explanation of the drawing]

FIG. 1 is a plan view schematically showing a continuous manufacturing apparatus for synthetic resin pipes suitable for applying the present invention, and FIG. 2 is a cross-sectional view showing a central cross-section of a winding core used in the apparatus shown in FIG. 1. Figure 3 is a central cross-sectional view of the core mold shown schematically in Figure 2 using the present invention;
The figure is a cross-sectional view taken along section line 1-1 in Figure 3 in the direction of the arrow.
The figure shows a partially cutaway side view of the inlet side sealing device, and FIG. 6 is a right front view of FIG. 5. FIG. 7 is a rear view of the outlet side sealing device, showing the left side of FIG. 8, and FIG. 8 is a sectional view showing the outlet side sealing device.
1... Machine drive device, 2... Hollow fixed shaft, 3... Hollow rotating shaft, 4... Mandrel frame, 5...・Sliding member, 6...Cam, 7...Belt, 8...Release tape,
9...Resin-impregnated nonwoven fabric, 10...Glass fiber, 11...Resin mortar, 12...
...Mixing device, 13...Glass fiber, 14...
... Resin-impregnated nonwoven fabric, 15 ... Heating furnace, 1
6... Formed tube, 17... Gear, 18.
... Support frame, 19 ... Fumarole drum, 20
... Fumarole, 21 ... Cold air introduction port, 2
2...Vent hole, 23...Side wall, 24.
... Fumarole, 25 ... Inlet side seal device, 26 ... Outlet side seal device, 27, 31 ...
...Beak-shaped guide member, 28, 30...Belt passage hole, 29...Split mounting ring.

Claims (1)

[Claims] 1 A core mold is formed by spirally winding a steel belt adjacent to the outer periphery of a rotating frame mold, a tube forming material containing a thermosetting resin is spirally wound around the outer periphery of the core mold, and the tube body is The forming material is wound around a core mold and hardened through a thermosetting furnace installed around its outer periphery, and the steel belt, which has been unwound spirally, passes through a hollow fixed shaft installed at the core of the core mold. In a continuous manufacturing apparatus for resin pipes configured to return to the winding start position,
A blow drum is provided inside the tip of the core mold, and cold air is introduced into the blow drum through the hollow fixed shaft, and the cold air is ejected toward the back surface of the steel belt and/or the bare inner surface of the formed tube. A continuous manufacturing device for synthetic resin pipes, characterized in that it is configured as follows.