JPH01301207A - Lining of inner face of pipe - Google Patents

Abstract

PURPOSE:To form a mortar lining with low water ratio nearly at the same low acceleration and in the same required time as in case of centrifugal projection laying, by giving micro-vibration to a pipe by means of a small projection of press roller while the pipe is rotated after applying mortar to the inner face of the pipe. CONSTITUTION:Outer peripheral face of both ends of a pipe 1 is rotatably supported by a plurality of rotating rollers 2 and a press roller 3. Application of mortar 9 to the inner face of the pipe 1 is implemented by rotating a screw 14 and a rotating blade 12, a kneader 17 being operated, and projecting the mortar 9 from the rotating blade 12. After the application of mortar 9 is finished, the pipe 1 is rotated at a speed of 15 to 30 revolutions per second, which can provide a centrifugal force corresponding to the acceleration of 5 to 30 G. In this case the press roller 3 rotates with the pipe 1 and a small projection 8 hits the outer surface of the pipe 1 to give micro-vibration to the pipe 1. Therefore, the mortar 9 laid on the inner face of the pipe 1 is fluidized by the micro-vibration to the pipe 1 and at the same time smoothed by means of centrifugal force due to rotation of the pipe 1. In such a manner, a smooth mortar lining 19 with low water ratio is formed in the pipe 1 for a short time.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for lining the inner surface of a metal pipe such as a cast iron pipe for forming a mortar lining on the inner surface of the pipe.

BACKGROUND OF THE INVENTION In the conventional lining construction methods of this type, two methods are generally used: centrifugal force construction and centrifugal projection construction.

The former type of centrifugal force construction involves pouring mortar with good fluidity at a high water ratio onto the inner surface of a rotating pipe and spreading it evenly. This method forms a mortar lining with a low water ratio by spinning for ~10 minutes to dehydrate and compact the mortar. In addition, in the latter centrifugal projection construction, mortar with a high water ratio, although lower than in the former case, is projected in the radial direction by a mortar projector and evenly distributed on the inner surface of the pipe, and the pipe is subjected to an acceleration of 20 to 30 G. This is a method of forming a smooth mortar lining by applying it for 15 to 30 seconds at a speed that produces centrifugal force.

Problems to be Solved by the Invention However, among the above conventional methods, according to centrifugal force construction,
To dewater and compact the high water ratio mortar lining,
Not only is it necessary to rotate the pipe for a long time at a speed that generates high acceleration, but the bending and ellipse of the pipe can cause uneven thickness of the mortar lining, and the problem of having to correct the ellipse of the pipe. was there. In addition, according to centrifugal projection construction, although the water ratio of mortar is relatively high, it is hydrophilic and
Since no compaction is performed, the mortar lining tends to crack, and since the mortar lining is soft immediately after construction, it is prone to sagging and peeling.

The present invention has been developed in view of these problems, and is capable of forming a mortar lining with a low water ratio similar to that achieved by centrifugal force application, with the same low acceleration and required time as centrifugal projection construction. The purpose is to

Means for Solving the Problems In order to solve the above-mentioned conventional problems, the method for lining the inner surface of a pipe according to the present invention involves lining the outer circumferential surface of the pipe with a plurality of rotating rollers and a presser roller having small protrusions on the outer circumferential surface. The mortar choreographer, which is rotatably supported and equipped with rotating blades for projecting mortar in the radial direction at the tip of the mortar conveying section, is a device that distributes mortar on the inner surface of the tube, and then rotates the tube. The structure is such that a mortar lining is formed on the inner surface of the tube by applying slight vibrations to the tube using the small protrusions.

Function: In the structure of the present invention described above, the mortar distribution device can distribute mortar with a low water ratio onto the inner surface of the pipe. Also, when the tube is rotated, the presser roller rotates together with the tube, and its small protrusions strike the outer circumferential surface of the tube, causing the tube to tighten slightly.
jtg! Let me do jJ. Therefore, the mortar distributed on the inner surface of the tube is fluidized by the slight vibrations of the tube, and is smoothed by the centrifugal force caused by the rotation of the tube. As a result, a mortar lining with a low water ratio is formed on the inner surface of the tube.

EXAMPLE Hereinafter, an example of the present invention will be described based on FIGS. 1 to 5.

In FIGS. 1 and 2, first, the outer circumferential surface of both ends of the tube 1 is rotatably supported by a plurality of rotating rollers 2 and a presser roller 3. As shown in FIG. Pipe 1 is a metal pipe such as a cast iron pipe.
The rotating rollers 2 are made of metal and support the lower part of the tube 1, and at least one of them is equipped with a rotational drive device (not shown).
are connected appropriately. As shown in FIGS. 3 and 4, the presser roller 3 includes a metal roller 7 rotatably supported on a rotating shaft 5 fixed to a bracket 4 via two ball bearings 6. The top of tube 1 is held down. At least one wear-resistant small protrusion 8 is fixed on the outer peripheral surface of the roller 7. Next, the mortar 9 is evenly distributed on the inner surface of the tube 1 by a device 10. , is a hardened mortar kneaded at the minimum water ratio required for the hydration reaction of cement (maximum slump value of 6 cm or less), and is completely lacking in fluidity. As shown, the mortar conveying section 11, which is equipped with a rotary blade 12 at the tip of the mortar conveying section 11, uses a screw conveyor to force-feed the mortar 9, which lacks fluidity, to the rotary blade 12. The zero-rotation vane 12 in which the screw 14 is rotatably provided inside the tube 13 is for projecting the mortar 9 from the mortar conveyance section 11 onto the inner surface of the tube 1 in the radial direction. The rear end of the mortar conveying section 11 has a plurality of blades 16 planted in the radial direction on the outer periphery of a boss section 15 that is rotatably supported at the tip.
As shown in FIG. 1, it is connected to a kneader 17. Kneading 1117 involves kneading the mortar 9 and transferring it to the mortar conveying section 1.
1, and is placed movably on a rail 18 laid in the axial direction of the pipe 1. The mortar 9 is choreographed onto the inner surface of the tube 1 by rotating the screw 14 and the rotary blade 12 while running the kneading R17, and by projecting the mortar 9 from the rotary blade 12.
When the choreography of mortar 9 is finished, accelerate tube 1 by 5 to 30.
Rotate for 15-30 seconds at a speed that provides a centrifugal force equivalent to G. At that time, the presser roller 36 rotates together with the tube 1, and the small protrusion 8 strikes the outer circumferential surface of the tube 1, causing the tube 1 to move slightly 1fj.
Make it move. Therefore, the mortar 9 distributed on the inner surface of the tube 1 is fluidized by the slight vibrations of the tube 1 and smoothed by the centrifugal force caused by the rotation of the tube 1. In this way, a smooth mortar lining 19 with a low water ratio is formed on the inner surface of the tube 1 in a short time. Since this mortar lining 19 has a low water ratio, there is no risk of cracking, and since centrifugal force cannot be applied for a long time, the cement paste layer will not separate into the surface layer.

By the way, Table 1 shows the comparative test results of various construction methods conducted by the inventor.
According to test numbers 6 to 10), the same low acceleration and required time as in the case of centrifugal projection construction (test numbers 3 to 5), and the same as in the case of centrifugal force construction (test numbers 1 to 2). This shows that it is possible to form a smooth mortar lining with a low water ratio.

The construction method of the present invention can also be applied to a method for forming a cylindrical body using mortar or concrete, a method for lining the inner surface of a cylindrical body using mortar or concrete, and the like.

Effects of the Invention As described above, according to the present invention, since mortar with a low water ratio is used, it is possible to form a mortar lining with a low water ratio without the risk of cracking. In addition, since high centrifugal force is not applied to the mortar lining for a long period of time, the cement paste layer does not separate to the surface layer.Furthermore, the mortar is fluidized by the small vibrations of the tube caused by the small protrusions of the presser roller, so the rotation of the tube A smooth mortar lining can be formed even if the centrifugal force based on the

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway explanatory diagram showing an embodiment of the present invention, Fig. 2 is a sectional view taken along the line ■-■ in Fig. 1, Fig. 3 is a front view of the presser roller of the present invention, Fig. 4 3 is a sectional view taken along the line IV-IV in FIG. 3, and FIG. 5 is a partially cutaway perspective view of the mortar choreography device of the present invention. DESCRIPTION OF SYMBOLS 1... Pipe, 2... Rotating roller, 3... Press roller, 8... Small protrusion, 9... Mortar, 10...
Mortar choreography is a device, 11...mortar conveyance section, 12
... Rotating vane, 19... Mortar lining. Agent Yoshihiro Morimoto Figure 3 Figure a

Claims (1)

[Claims] 1. The outer peripheral surface of the pipe is rotatably supported by a plurality of rotating rollers and a presser roller having small protrusions on the outer peripheral surface, and the tip of the mortar conveying section is equipped with rotating blades for projecting mortar in the radial direction. A mortar lining is formed on the inner surface of the tube by applying a slight vibration to the tube using the small protrusion while rotating the tube after distributing mortar on the inner surface of the tube using a mortar choreographing device comprising: A method of lining the inner surface of a pipe.