JPH06218601A - End face processor for plastic covered steel pipe - Google Patents

Abstract

PURPOSE:To make a device simple, efficient, and of superior finishing by providing a processing head equipped with a cutting edge and a steel pipe inner face support head having a stopper. CONSTITUTION:After a steel pipe 25 is accepted in an end face processor line, the steel pipe 25 is clamped by a steel pipe clamp cylinder 23. A processing head 2 and a cutting edge 4 are forced to advance so as to cut a plastic covered end face of a plastic covered part 26. A cutting completion position is decided by a recess position of an air hydrocylinder 10, which is controlled by a fine control stopper 11. As a result, centering of the steel pipe 25 in a processing head 2 is carried out by insertion of a steel pipe inner face support head 7 and free support structure of a steel clamp device 22. Thus superior finishing quality is provided without leaving any uncut finishing face.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an end surface processing apparatus for plastic coated steel pipes, and more particularly to an end surface processing apparatus capable of accurately finishing the end surface of a lining portion of a plastic coated steel tube within a predetermined dimension online. Is.

[0002]

2. Description of the Related Art Conventionally, a plastic-coated steel pipe in which polyethylene or the like is lined on the outer surface of the steel pipe has been used for applications such as weather resistance and corrosion resistance. In order to manufacture such a plastic-coated steel pipe, steel pipes cut to a predetermined length are connected in advance with a connecting tool, the connected steel pipes are passed through a lining device, and the steel pipe and the outer peripheral surface of the connecting tool are continuously connected. The plastic is coated to form a plastic coating.
After that, the plastic lining portion is run and cut at the steel pipe connecting portion, the connecting tool is removed, and the end surface of the plastic lining portion is finished to obtain a product.

However, the conventional end-face finishing of a plastic-coated steel pipe is manually performed online because of its strict tolerance. Therefore, it requires a lot of manpower, and there is a problem in terms of cost and efficiency. Therefore, an end surface finishing device for a plastic-coated steel pipe by automation is proposed. For example, as disclosed in Japanese Patent Laid-Open No. 3-281102, the processing head starts to move forward while rotating toward a steel pipe held by an automatic chucking device together with a backing plate, and moves forward to a predetermined position by fast-forwarding. When approaching the steel pipe end surface, the speed controller works, the cutting feed advances the machining head,
It is known as a processing device that cuts the end surface of the plastic coating part where the cutting tool bit projects from the steel pipe by this cutting feed.

[0004]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In Japanese Patent Publication No. 81102, the backing plate is projected from the cutting edge position of the processing head by a predetermined dimension, and during processing, the processing head and the backing plate move forward while maintaining this positional relationship. The finishing plate is finally contacted with the end surface of the steel pipe by cutting the steel plate, and the finishing processing is finished when the automatic chuck device is pushed against the spring force of the elastic slide device. in this way,
Since the automatic chuck device receives the pressing force of the backing plate, it must have an elastic slide device as an element, which makes the device extremely complicated.

Further, when the steel pipe is fast-forwarded to a predetermined position and approaches the end face of the steel pipe, the speed controller works to perform cutting feed, but the end face position of the steel pipe is not always at a constant position but within an error at the time of receiving. Variation occurs. Therefore, the installation position of the speed controller for switching from the rapid feed to the cutting feed has to be installed on the front side due to the variation, and there is a problem that the cutting feed amount becomes large and the efficiency becomes poor. Furthermore, since the center of the processing head and the center of the steel pipe are not always constant due to bending of the steel pipe, etc., there may be uncut portions of the coating part due to the radial limit of the backing plate and the cutting edge position, and there is a concern about quality problems after end face processing. To be done.

[0006]

In order to solve the above-mentioned problems, the inventors of the present invention have made as a result of keen creation, and as a result, the position of the processing head equipped with a cutting blade and the position of the end of the steel pipe, instead of the contact plate method. The equipment is extremely simple and highly efficient by using a completely different original method in which the steel pipe inner surface support head for the purpose of grasping and centering of the steel pipe and the machining head is separated so that it can move back and forth with respect to the machining head. (EN) Provided is an end surface processing device for a plastic-coated steel pipe having good quality. The gist of the invention is to install a processing device capable of advancing and retreating in the longitudinal direction of a coated steel pipe, and in this processing device, a processing head having a hollow cutting shaft and a rotatable cutting blade mounted on the front surface, The hollow portion of the working head is movable back and forth, and a truncated cone-shaped guide head is provided at the tip end, and a steel pipe inner surface support head having a stopper that is connected to this and abuts against the steel pipe end face of the coated steel pipe is provided. This is an end face processing device for plastic coated steel pipes.

[0007]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a partial cross-sectional side view showing an embodiment of the end surface processing apparatus according to the present invention. FIG. 2 is an enlarged view of the machining head and the end surface machining part of FIG. 1, (a) is a state diagram of a normal standby position before the start of cutting, and (b) is a state immediately before the start of cutting when the steel pipe inner surface support head abuts the steel pipe end surface. The state diagram, (c) shows the state diagram of the cutting end position when the machining head advances. Figure 3
(A)-(c) is explanatory drawing which shows the process of the end surface processing of a plastic coating steel pipe.

In FIG. 1, the processing apparatus 1 is an air cylinder 16 for shifting the processing apparatus, and is guided by a rail guide 17 along a rail 18 installed on a fixed bed 21 in the length direction of a plastic-coated steel pipe 25. Move forward and backward. The stroke of the air cylinder 16 is determined by the sum of the pipe end variation dimension A at the time of receiving, the inner surface insertion dimension B of the steel pipe inner surface support head 7 and a slight margin C,
In the case of the embodiment, 100 mm + 50 mm + 50 mm is 2
It was set to 00 mm.

On the other hand, the processing head 2 is constructed so as to rotate in a casing 14 of the processing apparatus via a bearing 15 and a drive motor 5 via a pulley and a belt 6.
The machining head 2 has a hollow shaft center and a steel pipe inner surface support head 7
Has a structure that allows it to move back and forth. On the front surface of the machining head 2, two cutting blades 4 are arranged in a well-balanced manner in a circumferentially symmetrical position and are housed in a cutting blade holder 3.

Further, the steel pipe inner surface support head 7 is attached to the tip of the center shaft 9 by a bolt 12 via a pressing plate 13, and has several types according to the size of the steel pipe and can be replaced. The rear end of the center shaft 9 is connected to an air-hydro cylinder 10 for feeding the cutting blade and shifting the steel pipe inner surface support head. The center shaft 9 includes an intermediate sleeve 19 and a metal bearing 8
The intermediate sleeve 19 is supported via the bearings 20 and is fixed to the machining head 2. Further, the air-hydro cylinder 10 is a double rod type, and the retreat limit is adjusted by the fine adjustment stopper 11 for positioning the end of cutting. The stroke of the air-hydro cylinder 10 is determined by the sum of the end surface machining allowance D of the plastic coating material and a slight margin E, and in the case of the present embodiment, each is 10 mm + 5.
It was 15 mm in mm.

When the end face of the plastic-coated steel pipe 25 is processed,
With the steel pipe clamp device 22, the chuck 24 is opened and closed by the vertical movement of the clamp cylinder 23 to clamp. Further, the pressure settings of the air cylinder 16, the air hydro cylinder 10 and the steel pipe clamp cylinder 22 are set so that clamp cylinder 22> air hydro cylinder 10> air cylinder 16 by a force acting in the pipe length direction on the steel pipe. .

[0012]

Next, the operation of the present invention will be described. First, when the steel pipe is received in the end face processing line, the steel pipe 25 is clamped by the steel pipe clamp cylinder 23. Next, replace the air cylinder 16 that was in the backward limit with the air hydro cylinder 10.
Moves forward in the forward limit state. Steel pipe inner surface support head 7
Comes into contact with the steel pipe end surface 27 and stops in the middle of the stroke.
At that time, the back pressure of the air-hydro cylinder 10 is a pressure corresponding to the pressing force of the air cylinder 16. When the back pressure of the air-hydro cylinder 10 is gradually reduced from this state to allow oil to escape, the air-hydro cylinder 10 retracts, and at the same time, the air cylinder 16 that was stopped halfway starts to move forward and is installed in the processing apparatus body 1. The processing head 2 and the cutting blade 4 that are present advance to cut the plastic-coated end surface. The cutting speed is adjusted by the back pressure oil flow rate control valve of the air-hydro cylinder 10, so that the optimum cutting speed can be easily obtained.

The cutting end position is determined by the backward limit position of the air-hydro cylinder 10, and the position is adjusted by the fine adjustment stopper 11. In the case of leaving a 0.1 mm coating on the finished surface, in the case of the present embodiment, since the position of the cutting edge of the cutting blade 4 fixed to the processing head and the steel pipe end surface contact step size of the steel pipe inner surface support head 7 are 15 mm, a fine adjustment stopper. 1
The position of 1 is set to 14.9 mm.

As a result, the steel pipe 25 is centered with respect to the machining head 2 by inserting the steel pipe inner surface support head 7 and the free supporting structure of the steel pipe clamp device 22, and has a good quality with no uncut portion on the cut finished surface. Also, since the retreat limit of the air-hydro cylinder 10 becomes the cutting end position and that position can be reliably performed with the mechanical stopper, a stable cutting end face alignment system can be obtained and the cutting allowance can be easily adjusted with the fine adjustment stopper 11. Became. further,
Even with variations in the steel pipe end surface when receiving the steel pipe, the steel pipe inner surface support head 7 in the air cylinder 16 causes the steel pipe end surface 2 to move.
It became possible to follow up in a short time until it touched 7. In addition,
In the above embodiment, one end face processing of the outer surface plastic coated steel pipe has been described, but it goes without saying that both ends of the plastic coating material can be alternately finished by disposing this apparatus at both ends.

[0015]

As described above, according to the present invention, a machining head equipped with a cutting blade and a steel pipe inner surface support head for grasping the positions of the ends of the steel pipe and centering the steel pipe and the machining head are machined. By using a completely different original system that is separated so that it can move back and forth with respect to the head, the conventional elastic slide device is not required, the structure is extremely simple, and the end face processing device for plastic coated steel pipe with high efficiency and good finish It was possible to provide.

[Brief description of drawings]

FIG. 1 is a partial sectional side view showing an embodiment of an end surface processing apparatus according to the present invention,

2 is an enlarged view of the processing head and the end surface processing portion of FIG.
(A) is a state diagram of a normal standby position before the start of cutting, (b) is a state diagram of the steel pipe inner surface support head abutting the end face of the steel pipe immediately before the start of cutting, and (c) is a state of the machining head advanced and the cutting end position Figure showing the figure,

FIG. 3 is an explanatory view showing a process of processing an end surface of a plastic steel pipe.

[Explanation of symbols]

 1 Processing Device Main Body 2 Processing Head 3 Cutting Blade Holder 4 Cutting Blade 5 Drive Motor 6 Pulley, Belt 7 Steel Pipe Inner Surface Support Head 8 Metal Bearing 9 Center Shaft 10 Air Hydro Cylinder 11 Fine Adjustment Stopper 12 Bolt 13 Holding Plate 14 Processing Device Main Body Casing 15 , 20 bearing 16 air cylinder 17 rail guide 18 rail 19 intermediate sleeve 21 fixed bed 22 steel pipe clamp device 23 clamp cylinder 24 chuck 25 steel pipe 26 plastic coating 27 steel pipe end surface 28 plastic coating end surface 29 connector

Front Page Continuation (72) Inventor Yasuhiro Sueuchi 1 Kimitsu, Kimitsu-shi, Chiba Nippon Steel Corp. Kimitsu Works Ltd.

Claims (1)

[Claims] 1. A processing device is installed so as to be able to move back and forth in the length direction of a coated steel pipe, and in this processing device, a processing head having a hollow cutting shaft and a rotatable cutting blade mounted on the front surface, A plastic-coated steel pipe characterized in that a hollow head is provided with a guide head of a truncated cone shape at a tip end thereof and a steel pipe inner surface support head having a stopper connected to the guide head and abutting against a steel pipe end face of the coated steel pipe. Edge processing device.