JPH03202317A - Centrifugal molding method of resin concrete pipe - Google Patents

Abstract

PURPOSE:To make it possible to efficiently produce a resin concrete pipe having smooth inner surface by a method wherein resin and aggregate are fed through separated feed routes to a mixing part, which is provided at an arm member, so as to be mixed with each other in order to discharge the mixed concrete material through a discharge port. CONSTITUTION:A resin feed unit 40, which is provided above a material feed arm 30, communicates with a resin feed port 36, which is bored at the upper part of an outer pipe, which locates at the boundary position between the agitating part of the resin feed arm and its aggregate feeding part. After being fed to a hopper, aggregate is fed by means of a screw blade 32 to the agitating part, which is provided on the tip side of the material feed arm 30. On the other hand, resin material is fed quantitatively by means of a compressor through the resin feed unit and resin feed port 36 to the agitating part. In the agitating part, the aggregate and the resin are mixed with each other by means of a plurality of pins 34, which are spirally and protrusively provided, and, at the same time, fed to the tip position of the material feed arm 30 so as to be ejected by means of resin concrete discharge blade 35 through an exhaust port 37 in the interior of an outer mold.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a centrifugal forming method for resin concrete pipes, and in particular, it is capable of smoothing the inner surface of resin concrete pipes and also enables efficient production of resin concrete pipes. This paper relates to a method for centrifugal molding of resin concrete pipes.

[Prior Art] Resin concrete pipes are high-strength and corrosion-resistant piping materials made of aggregate and resin materials, and centrifugal molding is generally used to manufacture resin concrete pipes. . In the centrifugal molding method, material is poured into the outer mold for tube forming while rotating the outer mold around its axis, and the material is formed into a tube shape using centrifugal force and solidified. This method involves taking the tube out of the mold, but as will be discussed later, it has been pointed out that the productivity is low.

Conventionally, various material supply devices have been used to pour materials into the above-mentioned outer mold for tube forming. There is a method of mixing aggregate and resin material to form a resin concrete material, and transporting and supplying this to the tip of the material supply device. Method (2) is disclosed, for example, in Japanese Patent Publication No. 61-45923, but the resin material and aggregate separate due to the difference in specific gravity, making the combined effect of both materials insufficient, and the aggregate As a result, as shown in FIG. 4, the inner surface of the tube is not flat, but has irregularities. In order to solve this problem, it is necessary to level the inner surface of the pipe using a sand-leveling plate, etc. as shown in Figure 4.5.
Productivity deteriorates significantly.

JP-A-62-24670 also discloses the method (■).
No. 4 discloses a method of first supplying aggregate and then supplying resin liquid, but this method requires a large centrifugal force of about 50 G to impregnate the resin between the aggregates. At the same time, there are restrictions on the thickness and particle size of the aggregate layer that can be impregnated with resin, and depending on the thickness of the resin concrete pipe to be produced, it is necessary to repeat the steps of supplying aggregate and impregnating with resin several times.

The method of Zarani ■ is disclosed in Japanese Patent Application Laid-open No. 64-42207, and in the previous conventional method, resin concrete containing room temperature curing agent adhered to the mixer or material input device and hardened, so centrifugal Focusing on the fact that cleaning work takes more time than molding, a thermosetting agent is used in place of the above-mentioned room temperature curing agent to prevent the resin concrete material from solidifying at room temperature and to facilitate cleaning. However, although this method can prevent the solidification of the resin, it is necessary to solidify the tube inner layer on a centrifugal device and then transfer it to a heating chamber to harden the tube body, which significantly impairs productivity. be.

[Problems to be Solved by the Invention] The present invention has been made by focusing on the above-mentioned circumstances, and it is possible to form a smooth inner surface of a resin concrete pipe without using special sanding means, and also to provide a highly productive centrifugal method. The aim is to provide a molding method.

[Means for Solving the Problems] The present invention which achieves the above object is to move an arm member of a tube material supply device back and forth in the longitudinal direction of the tube forming outer mold that rotates around the axis, and to achieve the above object. In a method of manufacturing a resin concrete pipe by discharging pipe material from a discharge port provided at the tip of an arm member, the resin and aggregate are mixed via separate feeding routes provided at the tip of the arm member. The resin and aggregate are mixed in the mixing section, and the mixed resin concrete material is discharged from a discharge port to form a resin concrete pipe.

[Function] In the present invention, aggregate and resin material are separately fed to the tip of the tube material supply device, and mixed immediately before being fed to the outer mold for tube forming to form a liquid resin concrete material. ,
The centrifugal force after discharge can easily spread the material and smooth the inner surface of the tube, so there is no need to flatten the inner surface of the tube by means such as a sand plate. Moreover, even without applying a particularly large centrifugal force,
A resin concrete layer in which the resin is sufficiently impregnated between the aggregates can be formed at once, and production efficiency can be improved. Furthermore, since the structure is such that the mixture is mixed just before the discharge port, even if most of the material that adheres to various parts of the molding equipment is unmixed, it can be easily removed, so even if room-temperature curing agents are used. There is no problem. In the end, production time can be shortened without the need for a heating process, and workability during cleaning can be greatly improved since there is no need to clean the material mixer, material feeder, etc. without using a thermosetting agent. becomes.

[Example] FIG. 1 is a schematic explanatory diagram showing the centrifugal forming of a resin concrete pipe according to the method of the present invention. The rotation mechanism of the outer mold 14 for pipe forming is the same as the conventional one, and as shown in FIG. 14 is rotatably mounted.

Further, the carriage 20 is configured to move in the directions of arrows XIMX2 so that the material supply arm 30 can be inserted into and withdrawn from the hollow portion of the tube forming outer mold 14.

Although the method of the present invention is not limited by the equipment used, a typical material supply arm 30 provided with a mixing section for resin material and aggregate will be described below.

FIG. 3 is a schematic explanatory diagram showing a typical example of the material supply arm. A rotating shaft 3 is located at the axis of the cylindrical material supply arm 30.
1 is disposed over almost the entire length of the material supply arm 30, and a hollow rotating shaft 33 with screw blades 32 formed on the outer peripheral surface of the rotating shaft 31, leaving a part on the tip side, is connected to the rotating shaft 31 through a bearing and a sealing material. The hollow rotating shaft 3
3 is configured to be able to rotate independently of the rotating shaft 31. The aggregate is fed forward by the rotation of the hollow rotating shaft 33. A plurality of bottles 34 are spirally protruded toward the outer circumferential direction on the outer circumferential surface of the rotating shaft 31 in a portion where the hollow rotating shaft 33 is not ring-mounted, and furthermore, a plurality of bottles 34 are provided on the outer circumferential surface of the tip end of the rotating shaft 31. Resin concrete discharge blade 3 consisting of a flat plate of
5 are arranged radially.

On the other hand, above the material supply arm 30 is a resin supply unit 4.
0, and communicates with a resin supply port 36 bored in the upper part of the outer cylinder, which is located at the boundary between the stirring section and the aggregate supply section of the material supply arm.

Furthermore, a resin concrete material discharge port 37 is provided at the lower end of the outer cylinder of the material supply arm.

Therefore, material supply is carried out as follows. First, the aggregate is supplied to the hopper, and then is fed by the screw blade 32 to the agitation section disposed at the tip side of the material supply arm 30. On the other hand, the resin material is quantitatively sent by the compressor through the resin supply unit and from the resin supply port 36 to the stirring section. In the stirring section, aggregate and resin are mixed by a plurality of spirally protruding pins 34, and at the same time, they are sent to the tip of the material supply arm 30, and the resin concrete discharge blade 3
5 into the outer mold from the discharge port 37.

Although the method of the present invention is not limited by the material of the resin concrete layer, for example, a mixture of crushed stone and/or silica sand and an inorganic fine powder filler (silica stone powder, calcium carbonate, etc.) can be used as the aggregate. An example of the resin is an unsaturated polyester resin, and a room temperature curing agent or the like may be added thereto.

Furthermore, in this embodiment, since the rotating shaft 31 and the hollow rotating shaft 33 are controlled by separate variable speed motors, the rotating speed can be changed depending on the particle size and composition of the aggregate, the type of resin material, etc. The materials can be mixed.

Furthermore, normally, the resin material to which a curing agent is added is fed to the resin feeding unit 40, but if a resin feeding unit is used that can feed the resin and the curing agent separately and mix them immediately before stirring, It is possible to further improve productivity by shortening curing time, etc.

[Effects of the Invention] Since the present invention is configured as described above, it is possible to provide a centrifugal forming method that can efficiently produce resin concrete pipes with smooth inner surfaces.

[Brief explanation of drawings]

Fig. 1 is a schematic explanatory diagram showing a centrifugal molding manufacturing apparatus for resin concrete pipes, Fig. 2 is a unidirectional arrow-view explanatory diagram showing the operating state of Fig. 1, and Fig. 3 is an illustration of the resin concrete supply section in the method of the present invention. Schematic explanatory diagram showing a typical example, Fig. 4, 's
FIG. 5 is a schematic explanatory diagram showing a conventional material supply arm. 10... Centrifugal molding device 13... Molding jig 14
... Outer mold for tube forming So ... Cart 30 ... Material supply arm 40 ... Resin supply unit third bacteria

Claims (1)

[Claims] The arm member of the tubular material supply device is moved back and forth in the longitudinal direction of the tube forming outer mold that rotates around the axis, and the tubular material is discharged from the discharge port provided at the tip of the arm member to form resin concrete. In the method for manufacturing a pipe, the resin and the aggregate are fed to a mixing part provided at the tip of the arm member via separate feeding routes, and the resin and the aggregate are mixed in the mixing part, A centrifugal forming method for a resin concrete pipe, which comprises discharging the mixed resin concrete material from a discharge port to form a resin concrete pipe.