JPS6257713A - Eccentricity measuring instrument for extrusion press - Google Patents

Abstract

PURPOSE:To directly measure the mutual eccentricity of the center at the outlet and inlet sides of a stem and container by fitting a center measuring panel on the inner face of the container inlet port and outlet port and by pressing the center indicating member engaged with the stem tip thereto. CONSTITUTION:The center indicating member 4 composed of a center 4a, sleeve 4b, etc. is fitted to the tip part of a stem 3. The center measuring panels 5, 6 that the center 5a, 6c are clarified are provided attachably and detachably on the inner face of the inlet port and outlet port of a container as well. In case of the measurement of the eccentricity, the measuring panel 6 is first fitted to the container inlet port and after pressing the center indicating member 4 fitted to the stem 3 thereto, the eccentricity is found by comparing the marked position and the center 5a by removing the measuring panel 5. It is similarly measured with the measuring panel 6 at the outlet port side as wel. Consequently the eccentricity mutual at the center at the outlet and inlet sides of the stem 3 and container 10 can directly be measured and with the correction thereof with the wall deviation of the extrusion steel pipe can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device for measuring the amount of eccentricity between a stem and each center on the entrance and exit sides of a container in an extrusion press method, which is one of the seamless steel pipe manufacturing methods.

[Prior art]

The extrusion press method, which is one of the methods for manufacturing seamless steel pipes, is carried out through the following work steps. First, the perforated heated billet is transported to the front of the container together with the dummy block, and while a mandrel is inserted into the dummy block and billet, the billet and dummy block are pushed into the container using a stem fitted onto the mandrel. Next, by pressurizing the stem and moving the billet forward, the billet is continuously passed through the concentric hole formed by the mandrel and the die, which is housed in a goo holder whose one end is fitted into the inlet of the platen and the other end is fitted into the inner surface of the container. The material is plastically deformed to form a pipe.

If the center of the stem does not match the center of the container entry side or the center of the container exit side in the above work process, a large uneven thickness may occur in the manufactured seamless steel pipe, or the outer surface of the stem may come into contact with the inner surface of the container. and damage one. Therefore, various methods have been proposed in the past for measuring the amount of eccentricity and the direction of deviation of the center of the stem with respect to the center of the container.

For example, Japanese Patent Publication No. 59-6726 discloses the following. Targets are installed on each of the main structural members such as a pressurizing raw cylinder (stem) and a container holder (container) in an extrusion press so as to be lined up in a straight line in the long sleeve direction. Each target is a circular object made of transparent material, and has a center and a standard scale of concentric circles centered on the center. Further, a telescope is installed at a position appropriately layered from the target in the long axis direction, and the telescope is aimed at the center of a target installed in the soil of one main component (for example, a container holder).

At this time, the amount of eccentricity is determined by reading the degree of misalignment between the telescope and the target on the other main components using a standard scale formed on the target camera 1-.

Also, as described in Japanese Patent Application Laid-Open No. 55-30673, X-
Considering the Y coordinate system, a projector that projects light in the X-axis and Y-axis directions toward the stem inserted into the container, and a base light shielding member in the X-axis and Y-axis directions of the container are provided,
By projecting light from the projector toward the stem, the light that has passed through the gap between the stem and the reference light shielding member is received by a linear sensor installed in front in the direction in which the light travels, and the number of bits of the received light is measured. There is a method of determining the amount of eccentricity by optically measuring the gap between the stem outer circumference and the reference point.

[Problem that the invention seeks to solve]

In the two measurement methods described above, the amount of eccentricity is simply determined from the relative positional relationship between the stem and the container.
There was a drawback that the amount of eccentricity between the center of the stem and the center of the container could not be directly determined.

Furthermore, although one of the major causes of uneven thickness is the misalignment between the stem center and the container center during pressurization, both measurements are performed while the stem is stationary, and the stem center and container center during pressurization. The drawback was that the amount of eccentricity from the center was not measured.

[Means for solving problems]

The present invention has been made in view of such circumstances, and by pressing a member to show off the center fitted to the tip of the stem to the center measurement board fitted to the inner surface of the container entrance and the inner surface of the container outlet, It is an object of the present invention to provide an eccentricity measuring device for an extrusion press that can directly measure the amount of eccentricity between a stem and the center of a container inlet/outlet side.

The eccentricity measuring device according to the present invention pushes a hollow heated billet into a container using a stem while inserting a mandrel into the inner surface of the billet, and then pressurizes and advances the stem to open a concentric hole formed by a die and a mandrel. In an extrusion press for extruding the hollow heated billet into a tube,
a center indicating member that is fitted to the tip of the stem and whose tip has a conical shape; and a disk-shaped center measuring board that is fitted to the inner surface of the container entrance and the inner surface of the container outlet, and the center is displayed on the surface thereof. and the center pointing member iiJ
The stem is pressed against the center measuring board, and the eccentricity between the stem center and the center on the container entry side and between the stem center and the center on the container exit side is measured based on the difference between the pressed position and the center. .

〔Example〕

Hereinafter, the present invention will be explained based on drawings showing embodiments thereof. FIG. 1 is a cross-sectional view showing the container inlet side of the eccentricity measuring device according to the present invention, and FIG. 2 is a cross-sectional view showing the outlet side. The container 10 includes a cylindrical liner l whose inner diameter is slightly larger than the outer diameter of the stem 3, and a liner holder 2 that fits around the liner l. A stem 3 is fitted onto a mandrel (not shown) and moves in the longitudinal direction.
The heated billet is pressed into a die (not shown).
It is extruded into a container holder through a concentric opening formed by a mandrel and a mandrel, and becomes a tube.

The center indicating member 4 fitted to the tip of the stem includes a center 4a, a sleeve 4b, a stem adapter 4c, a coil spring 4d, and a spring stopper 4e. A male thread 4g is formed on the outer circumferential surface of the proximal end of the stem adapter 4C, which has a stepped cylindrical shape with an outer diameter larger at the distal end than at the proximal end. A tapered center 48 whose distal end is conical and whose diameter becomes smaller from the large diameter part of the cone toward the proximal end has a flange 4f at its proximal end and a male thread 4h at its distal end,
Its inner surface is fitted into the sleeve 4b having a tapered hole that fits into the proximal taper of the center 48 from the distal end side of the sleeve 4b, with the distal end of the center 48 protruding. Then, the fitted center 48 and sleeve 4b are inserted into the stem adapter 4c from the proximal end side until the flange 4f is locked at the proximal end surface of the stem adapter 4C.

In addition, on the outer peripheral surface of the stem adapter 4c of the sleeve 4b,
A coil spring 4d is arranged surrounding this, and one end of this is in contact with the distal end surface of the stem adapter 4c.
Further, the other end is restrained by a spring stopper 4e having a female screw 41 that is screwed into a male screw 4h at the tip of the sleeve 4b.

Then, the male thread 4g formed on the stem adapter 4c of the center indicating member 4 configured as described above is screwed together with the female thread 3a formed on the inner circumferential surface of the tip end of the stem 3. and stem 3 are combined.

Here, a stem adapter 4c that constitutes the center indicating member 4,
Since both the sleeve 4b and the center 48 have the same axis as the stem 3, the conical tip of the center 48 coincides with the center of the stem 3 in FIGS. 1 and 2.

Next, we will explain the center measuring panels 5 and 6 that should be installed on the inner surface of the container entrance and the container outlet, respectively. The center measurement board 5, which has a stepped disc shape, has a small diameter portion approximately equal to the inner diameter of the liner 1, and the center measurement board 5 is placed at the proximal end of the liner 1 (container IO population) concentrically therewith. mated. - The force center measuring board 6 has an outer diameter equal to the inner diameter of the gland 7 at the tip end, an outer diameter equal to the inner diameter of the liner l at the base end, and a stepped hole on the inner surface of the base end. Consisting of a holder 6b having a through hole with a smaller diameter than the fixed hole, and a stepped disc-shaped center disk 6a that fits into the stepped hole of the holder 6b, the center disk 6a is fitted into the stepped hole of the holder 6b. After the die holder is fitted into the part where it is fitted during the extrusion press operation, that is, the inner peripheral edge of the gland 7,
Move the container 10 in the direction of the white arrow and attach it to the holder 6b.
Fit the outer surface of the proximal end of the liner to the inner surface of the exit side of the liner l. As shown in FIG. 3, a cross consisting of two straight lines passing through the center and orthogonal to each other is marked on the end surfaces of the large diameter portions of the center measuring plate 5 and the center plate 6a, that is, the surfaces in contact with the tips of the centers 48. The center 5a of the center measurement boards 5 and 6,
6c are clearly indicated.

Here, the center measurement board 5 is fitted concentrically to the inner surface of the entrance of the liner l, which is a component of the container IO, and the center measurement board 6 is fitted concentrically to the inner surface of the exit side of the liner l. The centers 5a and 6c are respectively containers 10
It represents the center position on the population side and exit side.

Furthermore, as shown in FIG.
It is inserted into the container 10 before the stem 3 is inserted into the container 10, and moves forward as the stem 3 moves forward, and eventually the holder 6b is inserted into the container 10. and applies pressure to the dirt.

Next, a specific method of measuring the eccentricity between the stem center and the center on the container entry side, and between the stem center and the center on the container exit side using the apparatus configured as described above will be described. First, the center measuring board 5 is fitted to the liner 1 at the container IO port, and the integrally assembled center indicating member 4 is screwed to the stem 3. Next, the stem 3 is advanced by °ζ towards the population side of the container 10 (in the direction of the white arrow in FIG. 1), and the center 4a is pressed against the center measurement board 5 to make a mark. The position of the mark made at the tip of the center 48 represents the center of the stem 3, and the center 5a represents the center of the container for 10 people. By comparing the center 5a, it is possible to measure the eccentricity 9 between the center of the stem 3 and the center of the container for 10 people, as well as the direction of eccentricity.

Next, after fitting the tip side of the center measuring board 6 to the ground 7,
After moving the container IO and fitting the proximal end side of the center measurement board 6 to the exit side inner surface of the liner 1, and inserting the pressure ring 8 into the container 10, the stem 3 is inserted into the container 10. , move this forward toward the inside of the container 10 (in the direction of the white arrow in Figure 2), press the tip of the center 48 against the center measurement plate 6 to mark the °ζ mark, and then remove the center surface plate 6. Comparing the marked position with the center 6c,
Since the mark represents the center of the stem 3 and the center 6c represents the center inside the container 10, the amount of eccentricity between the center of the stem 3 and the center of the exit side of the container 10 as well as the direction of eccentricity can be measured.

At this time, the holder 6b is passed from the stem 3 through the pressure ring 8.
When the pressure applied to the die is the same as that during actual pressing, the eccentric direction can be measured when the die is eccentrically placed under the same pressure as during pressing.

In this embodiment, the center measuring board 6 has a divided structure into the center board 6a and the holder 6b, but it may have an integral structure.

〔effect〕

FIG. 4 shows that the stem 3 is first inserted into the container 10 and the center is aligned by adjusting the gap between the outer peripheral surface of the stem 3 and the inner peripheral surface of the container 10 equally in the circumferential direction, and then the stem 3 is applied with each pressure. FIG. 4 is a measurement diagram showing an example of the result of pressing and marking the center 48 tip of the center indicating member 4 on the center measuring board 6 using the apparatus according to the present invention. In Figure 4, (a) shows the measurement results when only the prefill pressure is used, and (b) shows the measurement results when the pressure of the hydraulic cylinder that pushes the stem is lookkg/ca'i'.
, (T) is 12Qkg/cm2. (1) is 140
kir/am2. (E) is 160kg/am2.
(Force) represents the measurement result when it is 180 kg/cm2, and in Fig. 4, the origin is the center 6c of the center measuring board 6.
In this regard, . indicates the position of the mark made at the center 48, and the numerical value in (1) indicates the eccentricity (unit: fi) in each of the X-axis and Y-axis directions from the center 6c.

As can be understood from FIG. 4, even if the centers are adjusted in advance without applying pressure, applying pressure will cause the center 6c of the center measuring board 6 to be aligned with the position of the mark made at the center 48. Misalignment occurs, and the degree of misalignment varies depending on the magnitude of the pressing force. However, since this deviation is a major factor in the occurrence of uneven thickness, by correcting this deviation, uneven thickness can be significantly reduced.

Therefore, as described above, the device according to the present invention, which is capable of measuring the eccentricity between the stem center and the center of the outlet side of the container even during pressurization, can prevent the occurrence of uneven thickness, and has an excellent effect on steel pipe manufacturing using the extrusion press method. play.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing the container entrance side of the eccentricity measuring device according to the present invention, Fig. 2 is a cross-sectional view also showing the container outlet side, Fig. 3 is a front view of the center measuring board, and Fig. 4 is the present invention. It is a measurement diagram when using the eccentricity measuring device according to .

Claims (1)

[Claims] 1. Push the hollow heated billet into the container using the stem while inserting the mandrel into the inner surface of the billet, and then push the stem forward under pressure through the concentric opening formed by the die and the mandrel. In the extrusion press for extruding the hollow heating billet into a tube, a center indicating member is fitted to the tip of the stem and has a conical tip; It is equipped with a disk-shaped center measuring board whose center is displayed on the surface, and the center indicating member is pressed against the center measuring board, and the center of the stem and the center of the container entry side are determined based on the difference between the pressed position and the center. and an extrusion press eccentricity measuring device, characterized in that it is configured to measure the amount of eccentricity between the center of the stem and the center of the outlet side of the container.