JPS61175005A - Forming device for cement slurry film for cement pipe - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for manufacturing cement pipes, and more particularly to an apparatus for forming a film of cement slurry (hereinafter simply referred to as slurry) for cement pipes.

It is known to manufacture reinforced cement pipes by wrapping a slurry film formed on a length of base fabric in a glue-like manner around a winding shaft.

[Conventional technology]

A conventionally used cement slurry film forming device for cement pipes (hereinafter simply referred to as slurry film forming device) in which cement layers and base fabric layers are alternately formed is shown in Figs. 4 to 6.
The diagram will be explained. Figure 4 is a schematic side view of the conventional device;
FIGS. 5 and 6 show one end of a cross-section in the width direction of a slurry film obtained by a conventional apparatus.

A first film-forming roller 2 and a second film-forming roller 3 made of steel or the like are arranged side by side with a predetermined gap between them below a hopper l that supplies slurry S suitably mixed in advance with a mixing device. do. The film forming rollers 2 and 3 are both driven by drive rollers and rotated in the direction of the arrow (for example, at a surface speed of 4 to 16 m/min), and the slurry film formed on the base fabric B, such as cheesecloth, supplied between both film forming rollers. Primary control of the thickness (for example, 1 to 4 mm) is performed.

A net conveyor 4 is arranged approximately horizontally below the second film forming roller 3 with a predetermined gap from the second film forming roller 3, and the base fabric passing between the film forming rollers 2. B is further transferred onto the net conveyor 4. The net conveyor 4 has SU around the driving roller 5, driven roller 5, and driven roller 6.
The driven roller 6 is located directly under the second film forming roller 3, and the net 7 on the driven roller 6 and the second film forming roller 3 are wound around each other. Secondary control of the slurry film thickness is then performed between the net 7 and the doctor plate 8, and the slurry is transferred to the next step by the net converter 4. In this case, the doctor plate 8 is
It also has a separation function between the roller 3 and the slurry film during film formation.

9 is a scraper, and 10 is a slurry recovery belt conveyor.

In the slurry film forming apparatus described above, the width of the hopper 1 is adjusted to be approximately equal to the width of the base fabric B, and the maximum width of the hopper is, for example, about 3.000 mm. Also, film forming rollers 2, 3,
The width of the rollers 5, 6 and the net 7 of the net conveyor is, for example, about 3.200 mm. Therefore, the width of the base fabric B is always smaller than the width of each roller and the net, and since the width of the slurry is expanded by being pressed by each roller, the width of the base fabric B is smaller than the width of the slurry.

In the above-mentioned cement pipes, which are manufactured by winding a slurry film formed on a base fabric in a paste-like manner, the thickness of the slurry film in the longitudinal direction is adjusted to improve the diameter and finish of the product. The thickness and thickness in the width direction are evenly balanced;
and must be uniform in length in the longitudinal direction. However, since the uniformity of the length is related to the slurry and base fabric cutting device located in the next step of the apparatus of the present invention, the former will be explained in this specification.

[Problem that the invention seeks to solve]

As can be seen from Fig. 4, when using the conventional device, the first control of the slurry film described above is accurate, but the second and third control is accurate.
At the next control point, the portion of the slurry S that protrudes from the base fabric is also transferred from the film forming roller 3 to the net conveyor 4, and the slurry enters the net 7, making the movement of the belt conveyor inaccurate.

That is, if the supplied slurry S is in an excessive amount, the slurry S will be squeezed out from the base fabric B in the width direction on the net 7 as shown in FIG. In this case, the protruding part of the slurry S remains on the net 7, causing the inconvenience of frequent cleaning of the net, or the remaining part of the protruding part remains on the winding shaft (not shown) when the slurry is wound around the winding shaft (not shown). If it adheres to areas where it is not necessary to wrap it, it can cause a decline in product productivity and quality. Furthermore, the slurry S that has been sucked out from the base fabric B cannot be recovered.

If the slurry S is supplied in a slightly insufficient amount in consideration of the above, the slurry will be insufficient at the width direction ends of the base fabric B as shown in FIG. 6, and the finished cement pipe will likely have an insufficient outer diameter at the ends.

[Means to solve the problem]

The present invention eliminates the above-mentioned drawbacks of conventional slurry film forming apparatuses. Two film-forming rollers are arranged parallel to each other in a substantially horizontal manner, and a second film-forming roller is provided below the second film-forming roller.
A third film-forming roller is arranged in parallel with a predetermined gap in the vertical direction from the film-forming roller, and the surface of the second film-forming roller facing the third film-forming roller has a tip thereof facing the third film-forming roller. Arrange a doctor plate that is in contact with the second film forming roller, and place the net conveyor almost horizontally at a position with an appropriate gap from the third film forming roller and not higher than the level of the third film forming roller. The base fabric is placed between the first and second film forming rollers, then the second film forming roller. A cement layer and a base fabric layer are alternately formed by passing the cement slurry between the third film forming rollers and continuously guiding it onto the net conveyor, and supplying the cement slurry onto the base fabric via the hopper. This is a cement slurry film forming device for cement pipes.

〔Example〕

The apparatus of the present invention will be described with reference to FIGS. 1-3.

Since the present invention is an improvement over the conventional device described above, members common to the conventional device are designated with the same reference numerals.

As shown in FIG. 1, the device of the present invention differs from the conventional device (FIG. 4) in the following points.

That is, below the second film forming roller 3, there is a third film forming roller 1 at a predetermined distance in the vertical direction from the second film forming roller 3.
1 in parallel. A scraper 12 is provided on the lower surface side close to the third film forming roller 11.

In this case, the scrapers 9 and 12 are used to scrape off the slurry on the film forming roller 2.11 that has been scraped off from the base fabric B, and the scraped slurry is collected by a common slurry collection belt conveyor 10. be done.

The driven roller 6 of the net conveyor 4 transfers the slurry on the third film forming roller 11 to the net conveyor 4.
The net conveyor 4 is provided with an appropriate gap from the film forming roller 11 so as not to transfer and adhere to the film, and the level of the net conveyor 4 is arranged slightly lower than the level of the third film forming roller 11.

To explain the operation of the device of the present invention, a base fabric B such as cheesecloth is first placed. between the second film forming rollers 2 and 3, then the second film forming rollers 2 and 3; The net conveyor 4 is inserted between the third film forming rollers 3 and 11.
Lead upwards in a continuous manner. On the other hand, a slurry film is formed on the base fabric B by the slurry S supplied via the hotter 1.

The gap between each film forming roller fixes the axial position of the second film forming roller 3, the first film forming roller 2 is horizontal as shown by arrow 13, and the third film forming roller 11 is shown as arrow 14. It is convenient to move and adjust vertically.

Second. After passing between the third film-forming rollers, the slurry that has not adhered to the second film-forming rollers is separated by a scraper 8, and the slurry thickness is tertiary adjusted between the scraper 8 and the third film-forming rollers. . The thickness of the slurry S formed on the base fabric B in the longitudinal direction is extremely uniform since the net 7 is not present.

While the secondary and tertiary control of the slurry film in the conventional device is incomplete, in the device of the present invention, all of the first to tertiary controls function, so the slurry film thickness in the length direction can be reduced. Control is complete.

As shown in FIG. 2, second and third film forming rollers 3, 1
The slurry film on the base fabric B transferred from the gap 1 to the net conveyor 4 does not have the ears 15 that were present on the third film forming roller. 1
The slurry is removed by adhering to the surface of the slurry 1, scraped off by the scraper 12, and collected by the slurry collection belt conveyor 10, so that it does not adhere to the net 7 of the net conveyor 4. Therefore, contamination of the net 7 is prevented. That is, the third film forming roller 1
1 can be said to have the function of a take-up roller. FIG. 3 shows a part of a cross section in the width direction of a slurry film obtained according to the present invention.

〔Effect of the invention〕

With the configuration as described above, the following effects can be obtained according to the present invention.

■ There are three control points that allow complete thickness control.
In addition, since there is no net of the net conveyor at this location, the slurry thickness is extremely uniform.

■ All the slurry ejected from the base fabric on the third film forming roller adheres to the surface of the third film forming roller and is removed.
There is no need to wash the net, and there is no need to form a portion of only slurry that does not need to be wound on the winding shaft for making a cement tube by winding the slurry film together with the base fabric in a subsequent process. Therefore, a slurry film having a uniform thickness in the width direction can be obtained.

(2) All the edges of the slurry film transferred to the third film forming roller can be collected by the collection belt conveyor and returned to the hopper via the mixing device, improving the slurry yield.

[Brief explanation of drawings]

Fig. 1 is a schematic side view of the apparatus of the present invention, Fig. 2 is a front view showing the main parts of the apparatus of the invention, and Fig. 3 is a partial cross-sectional view in the width direction of a slurry film obtained by the apparatus of the present invention. FIG. 4 is a schematic side view of a conventional apparatus, and FIGS. 5 and 6 are partial cross-sectional views in the width direction of a slurry film obtained by the conventional apparatus. 1... Hopper, 2... First film forming roller,
3... Second film forming roller, 4... Net conveyor,
11...Third film forming roller, B...Base fabric, S...
...Cement slurry.

Claims (1)

[Claims] 1. A device that forms a cement slurry film of a certain thickness on a base fabric such as cheesecloth when manufacturing cement pipes in which cement layers and base fabric layers are formed alternately, and which uses pre-blended cement. Below the hopper for supplying slurry, first and second film forming rollers are arranged parallel to each other with a predetermined gap therebetween, and below the second film forming roller, the second film forming roller is installed. A third film-forming roller is arranged in parallel with a predetermined gap in the vertical direction from the film-forming roller, and the surface of the second film-forming roller facing the third film-forming roller has a tip end facing the second film-forming roller. A doctor plate (in contact with the film roller) is arranged, and the net conveyor is placed in a substantially horizontal position with an appropriate gap from the third film forming roller and at a position not higher than the level of the third film forming roller. The base fabric is passed between the first and second film-forming rollers, then between the second and third film-forming rollers, and continuously guided onto the net conveyor, and passed through the hopper. A cement slurry film forming device for cement pipes that supplies cement slurry onto a base fabric.