JPS5848688B2 - Processing method for fixing the end of PC steel wire in concrete pile - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a figure-8-shaped PC steel wire head fixing plate in a concrete pile, and more particularly to a method for processing a fixing hole in a PC steel wire head.

In the conventional processing method, the first step: drilling the tap pilot hole, the second step
Process: Belly button pressing process, 3rd process: Figure 8 hole punching process, 4th process: Tap process, as it was processed from the 4th process,
In the head fixing hole (hereinafter referred to as PC hole) of the figure 8 PC steel wire processed by this processing method, so-called sag and distortion occur along the end face of the PC hole and its periphery.

This is especially unsuitable for use as a joint end plate where flatness is essential, and the appearance is also unsatisfactory.

Also, when inserting the PC steel wire into the PC hole, the upper part of the PC steel wire head may protrude from the end surface of the fixing plate.
Even if you want to make the PC hole deeper than the standard dimensions, with the current processing method, there is a risk of shear cracks occurring in the machined part, so although it is possible to machine it deep, it is extremely dangerous. It is.

In order to satisfy these requirements, drilling using a drill press can solve the problem, but the processing takes a long time and increases costs.

Therefore, the present invention was proposed in an attempt to eliminate such current defects.

Hereinafter, one example of the present invention will be described in detail based on the attached drawings.

1 is an 8-shaped PC steel wire head fixing plate called a joint.

(Hereinafter, it will be simply referred to as a fixing plate.) As a first step, the fixing plate 1 is subjected to a pilot drilling process for tapping holes 2.

As a second step, a hole 3 is punched out on the side of the tapped hole 2.

The diameter of the upper part of this hole 3 is made as large as possible, but the diameter of the lower part can be made comfortably smaller than the diameter of the PC steel wire.

As a third step, a hollow press-drawn hole 4 is formed from the upper surface of the hollow hole 3 to form a seat for the head of the PC steel wire.

At the same time, when pressing the navel press-drawn hole 4, a protrusion 5 is formed on the back surface of the fixing plate 1.

Of course, in such processing, pressing is performed from the upper surface with a belly button press punch, and at the same time, a die corresponding to the projection 5 is brought into contact with the rear surface.

As the fourth step, a figure 8 hole punching process is performed.

That is, using a figure-8 hole punch and guide pin on the surface,
This processing can be performed by abutting a concave die for the guy into which the protruding bevel fits on the back side.

Through this process, the figure 8 hole 6 is processed and at the same time the pilot hole 2 and the drop hole 3 of the tap are completed as a tapped hole and a hole for inserting a PC steel wire, respectively.

As a fifth step, the tap hole is tapped.

1. Since the embodiment of the present invention relates to the steps described above, the most noticeable effect is particularly in the second step of punching holes.

Since the current Karo construction method does not have this, it has various deficiencies that will be described later. However, the process of the present invention has this hole punching process, so the pressing force of the third process can be reduced. The hole can be formed extremely smoothly, and there is no sag on the hole end face or any distortion around it.

That is, all of the sag or distortion that occurs during press working with the belly button press punch is absorbed by the forehole, and no sag or distortion occurs on the hole end face or its surroundings.

Hereinafter, a comparison will be made between a product processed using the current processing method and a product processed using the present invention.

As described above, the processing method of the present invention has extremely significant industrial effects compared to conventional processing methods.

[Brief explanation of the drawing]

The figures show one embodiment of the present invention, in which Figure 1 is a plan view of the fixing plate, Figure 2 is a sectional view taken along the line A-A in Figure 1, and Figures 3 to 5 show various processing methods of the present invention. It is a longitudinal side view explaining a process. Explanation of symbols, 1... Fixing plate, 2... Tapped hole, 3... Discarded hole, 4... Hen pressed and drawn hole, 5...・・・Protrusion, 6...8 figure hole.

Claims (1)

[Claims] 1. Drill a pilot hole 2 on the figure 8-shaped PC steel wire head fixing plate 1, then punch a hole 3 on the side of the tapped hole 2,
After that, a hollow press-drawn hole 4 is formed in the hollow hole 3, and a protrusion 5 is formed on the back surface thereof, and then the tapped hole 2, the hollow hole 3, and the hollow press-drawn hole 4 are communicated with each other. A method of processing an end fixing seat of a PC steel wire in a concrete pile by punching a figure-8 hole 6 and tapping the tap hole 2.