JP4092287B2 - Drain pipe prevention tool - Google Patents

Description

  The present invention relates to an anti-drawing tool for a water collecting pipe, and an object thereof is to prevent the water collecting pipe from being pulled out by pulling out a drill pipe to the front of the surplus portion and installing a tip cone at the surplus portion.

  In general, when collecting groundwater with a large amount of drainage, it is extremely difficult to insert the water collection pipe. However, when the casing is pulled out, earth and sand together with the groundwater flows into the casing, resulting in a jamming phenomenon. Phenomenon that is pulled out together.

  In the case of such a phenomenon, as a countermeasure against the past, a carbon steel pipe (gas pipe) for SGP piping is used as the water collecting pipe instead of the hard vinyl chloride pipe water collecting pipe, and a metal crown is attached to the tip of the gas pipe to penetrate the rock. I have devised it so as not to get out. However, gas pipes had to be managed early for many years because of the environment such as water and soil conditions.

Therefore, as shown in Patent Document 1, a technique for preventing a water collecting pipe embedded in the ground from coming out of the soil has been disclosed.
Japanese Unexamined Patent Publication No. 2000-110170

In the invention of the above-mentioned Patent Document 1, the base end portions of a plurality of diameter-enlarged bars are pivotally fixed inside the distal end of the fixed cylinder, and the spring is housed in the sliding cylinder that fits into the fixed cylinder the biasing of the tip of the enlarged diameter bar through the slit of the fixed cylinder and the sliding cylinder is a configuration adapted to the enlarged diameter extending outside the tube. However, since the diameter expansion bar is a rod shaft, the diameter does not increase by itself unless the spring is biased. Then, the tip of the spring's receiving part had to be extended.

Accordingly, in order to solve the problems of the prior art and achieve the object of the invention, the present invention provides a pull-out prevention device for a water collecting pipe, a bending base at the top end surface of a truncated cone cone body to be attached to the tip of the water collecting pipe. a plurality of leaf spring over the end the entire length of the tip is flat shaped while disposed toward the radially top of the cone body bent base end portion of the plurality of leaf springs via a mounting member and a bolt It is fixed to the end face .

  Since the present invention is configured as described above, the following effects can be obtained. In other words, by providing a plurality of leaf springs with their own elastic repulsive force on the cone body attached to the tip of the water collection pipe, the diameter of the drill pipe is as small as possible against the elastic repulsive force (nominal It is confined to the inner diameter of 95 mm). And when it remove | deviates from a drill pipe, it will expand to the maximum diameter (125 mm), Therefore Pull-out prevention of the water collection pipe inserted in the drilling hole can be performed very reliably.

In this case, since the plurality of leaf springs are attached close to (about 25 mm) the tip of the water collecting pipe, there is very little extra digging forward from the tip of the water collecting pipe by the drilling bit at the tip of the drill pipe . Further, since the contact distance with the water collecting pipe is short when the drill pipe is pulled out, the pulling action generated in the water collecting pipe is small, and the time for applying the pushing pressure to prevent the drawing action can be shortened.

  Next, the best mode for carrying out the present invention will be described. The maximum diameter of the leaf spring of the tip cone for preventing the withdrawal of the water collecting pipe is 125 mm, and the nominal diameter of the drill pipe can be relatively smoothly inserted into the inner diameter cross section of 95 mm, and can correspond to the drilling diameters of 95 mm and 115 mm. It is like that.

  The connecting portion of the tip cone is tapered and can withstand a pulling force of about 2.0 kN just by inserting it into the tip of the water collecting pipe and hitting it with a small hammer to a specified point with a step.

  This tip cone body installation method is designed to prevent the drainage pipe from coming out by pulling out the drill pipe to the front of the surplus portion and placing the tip cone at the surplus portion.

Reference numeral 1 denotes a water collecting pipe, which is generally a hard vinyl chloride pipe of the standard “VP-40”. 2 is a cone body, the head 2 ₁ form a truncated cone, and the body portion 2 ₂ a stepped portion to allow charging to a depth of tapping a small hammer setting the tip of the water collecting pipe 1 Is molded. The cone angle θ in the illustrated example is set to 35 degrees. 3 is a relatively elongated leaf spring, one end portion causes along the conical surface 2 ₂ of the cone body 2, in Bangasa shaped open wants against the top end face 2 ₃ by bending the base end portion 3 ₁ In addition, a plurality of sheets (six in the illustrated example) are arranged radially. In the illustrated example, the thickness t of the leaf spring 3 is set to 1.2 mm, and the length L is set to 83 mm. 4 is a mounting seat plate with holes, the bent base end portion 3 of _the largest diameter R = 125 mm of the leaf spring 3 of the top end surface to the leaf spring plate mounted radially the cone body by fixing by spot welding or the like is there. 6 is a bolt mounting through hole 5 of the seat plate 4 on top end surface 2 ₁ of the cone body 2.
"Specific work process examples"

Has an inner diameter of nominal diameter 95mm crawler drill, and the drill pipe 8 having a drilling bit 9 with the blade portion 10 of the drilling bit at the distal end, continue to drilling in set sideways depth from the slope. Then, the drill pipe 8 and the inner rod 7 are continuously inserted in accordance with the depth of the drilling hole H, and the drill pipe and the inner rod reach a predetermined depth. (Fig. 4)

  The drill pipe 8 and the inner rod 7 that have reached a predetermined depth are pulled out only by the inner rod 7 while leaving the drill pipe 8. (Fig. 5)

  The water collecting pipe 1 with the cone body 2 attached to the opening at the tip is inserted into the drill pipe 8 in which the inner rod 7 has been pulled out. At this time, the leaf spring 3 that opens in the shape of a umbrella is squeezed while resisting the elastic repulsive force, and is pushed forward in a state of being completely stored in the drill pipe. (Fig. 6)

When the tip of the water collecting pipe 1 reaches the tip of the drill pipe 8 and the insertion of the water collecting pipe is completed, the drill pipe 8 is pulled out. At this time, when the drill pipe 8 starts to be pulled out, the water collecting pipe 1 also has a pipe pulling action together with the drill pipe, so that a pressing force is appropriately applied to the water collecting pipe 1 so as not to come out. Then, the drill pipe 8 is withdrawn when the tip section is more than the tip 3 ₂ of the leaf spring 3 of the cone body 2, the plate springs 3 which has been narrowed in the pipe is expanded to drilling H by the elastic repulsive force Press contact with the inner surface. In this state, when a pulling-out action is generated in the water collecting pipe, the tip of the leaf spring 3 that is radially expanded radially bites into the inner surface of the drilling hole, thereby preventing the collecting pipe from coming off. (Fig. 7)

It is a front view of the drawing-out prevention tool of the water collecting pipe which concerns on this invention. It is a longitudinal cross-sectional view which follows the 2-2 line of FIG. It is a longitudinal cross-sectional view of the state which inserted the water collection pipe with a cone main body into the drill pipe. 4 to 7 are explanatory views showing work steps using the water collecting pipe pull-out preventing device according to the present invention, and FIG. 4 is a longitudinal section in which a drill pipe and an inner rod are drilled to a predetermined depth and inserted. FIG. It is a longitudinal cross-sectional view of a state where only the inner rod is pulled out from FIG. It is a longitudinal cross-sectional view of the state which has inserted the water collecting pipe with a cone into the drill pipe which pulled out the inner rod. It is a longitudinal cross-sectional view of the state which has pulled out the drill pipe leaving the water collecting pipe reaching the drilling hole tip.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Water collecting pipe 2 ... Cone body 3 ... Leaf spring 4 ... Leaf spring attachment member 5 ... Hole of attachment member 6 ... Bolt 7 ... Inner rod 8 ... Drill pipe 9 ... Drilling bit 10 ...... Blade part of drill bit

Claims (1)

Flat across the entire length of the tip (3 ₂ ) from the bent base end (3 ₁ ) on the top end surface (2 ₃ ) of the truncated cone cone body (2) to be attached to the tip of the water collecting pipe (1) a plurality of leaf springs which are molded (3) while located radially directed, cone body bent base end portion of the plurality of leaf springs (3 ₁₎ through a mounting member (4) and the bolt (6) A water collecting pipe pull-out preventing device characterized by being fixed to the top end surface (2 ₃ ) of (2).