JPS58166015A - Manufacture of covered metallic pipe - Google Patents

Abstract

PURPOSE:To prevent the covering of effective portions from being damaged when several metallic pipes conveyed in a row are heated and the external surfaces are covered to manufacture covered metallic pipes by a method wherein the end portions of said connected pipes is detected after the covering process, and metallic pipes are conveyed while holding this end portion and then cooled. CONSTITUTION:Metallic pipes W, W successively supplied are connected in advance by a connecting jig 2 that is inserted into the inside of the rear end of the foregoing metallic pipe W and the inside of the front end of the succeeding pipe W, are passed through a heater 1a, heated, then, passed through a circular die 1b, to obtain a covered metallic pipe W' where the outer surface of the metallic pipe W is covered with anticorrosive layer. the end portion of the connecting pipe is detected by a detector 4 and the neighboring portion of said connecting pipe end is hung by wires 7a, 7b to feed the covered metallic pipe W'. These wires 7a, 7b are made to hold the pipe ends that will be cut off later. Thus, the covered portion of the metallic pipe undergoes no damage.

Description

DETAILED DESCRIPTION OF THE INVENTION The method for manufacturing the Fi-coated metal tube of the present invention Kla L, and #
Specifically, the present invention relates to a method for preventing damage to the coating portion when manufacturing a coated metal tube by heating the metal tube and subjecting its outer surface to KIIWI treatment.

When metal tubes are used in their original state, problems often arise in their corrosion resistance, appearance, etc., and as a countermeasure to these problems, anti-corrosion treatments and coating treatments such as painting are carried out. Ordinary coated metal pipes use hot-melt adhesives, and do not require heating of the metal pipes, and even after being coated, they can be cooled with water using the Java method and transported on conveyor rolls. There will be no damage to the covered parts.

However, depending on the intended use, a coated metal tube with high adhesion may be required, and the method for coating this type of metal tube is generally to heat the metal tube and then apply extrusion coating. When conveying on a conveyor roll while cooling with water after applying a certain coating treatment, damage to the coating at the bottom of the metal tube that comes into contact with the conveyor roll, such as denting of the bottom of the metal tube due to the weight of the metal tube itself, There are problems such as dark contact scratches with the conveyor roll and poor adhesion of the coated layer.

Zero-fired #4Fi was developed to solve this problem, and when manufacturing metal tubes that were coated with tube heating, it caused damage to the lower coating of the metal tube that came into contact with the conveyor roll during transportation. The purpose is to provide a method that does not cause

The method for manufacturing a coated metal tube according to the present invention is a method for manufacturing a coated metal tube by heating a plurality of metal tubes that are connected and conveyed one after another and applying a coating treatment to the outer surface of the tube. The present invention is characterized in that the end of the connecting pipe is detected, the end of the connecting pipe is held and conveyed, and the coated metal pipe is cooled.

The method of the present invention will be explained below based on an open view showing an example thereof. FIG. 1 is a schematic side view showing equipment for carrying out the method of the present invention. IFi extrusion coating equipment with metal "IIW" fed in succession.

W is connected in advance by a connecting jig 2 fitted into the rear end of the preceding metal tube W and the inside of the tip of the slowly moving metal tube W, and a driving force is applied by the pinch roll 3 to connect the metal tube W as shown in the white figure. The outer peripheral surface of the metal tube W is coated with an anti-corrosion layer by passing it forward in the direction of the drawing arrow and heated to 170 to 190° C. to 170 to 190° C. to form a coated metal tube. This is a device for obtaining W'.

Immediately downstream of the extrusion covering device 1, there is a suspension starting device 5.
is provided. This suspension starting device 5Fi is composed of a rail 5m for placing and guiding the trolley 6, a support member 5b for supporting the downstream end of the rail 51, and a cylinder 5c having a rond tip connected to the upstream end of the rail 5m. 5c
The rail 5a is rotated about the support member 5b by the advancing and retracting movement of the carriage 6 and the rail 5a on which it is placed.
It is possible to keep the rail 5a in a horizontal state vB (the state shown by the line ! in the figure) and in a state in which the upstream side of the rail 5a is slightly inclined downward (the state shown by the broken line !l in the figure). Furthermore, rail 5
Needless to say, a stopper (not shown) is provided to prevent the cart 6 from rolling and falling when the cart 6 is slightly inclined. Two wires 7a and 7b are connected to the upstream side and the downstream side of the nine bogie 6 placed on the rail 5a so that both wires 7a and 7b form a U-shape when viewed from the front.
The wires 7m and 7b are suspended so that the attachment part to the pipe can be removed, and the distance between the wires 7m and 7b is such that when the coated metal pipe W is suspended, the end of the pipe that is to be cut off is held. The total length of the wires 7a, 7b is such that the wires 7a, 7b surround the lower half of the coated metal tube V coming out of the extrusion coating device 1 when the trolley 6 is held horizontally. The length is necessary and sufficient to allow it to be hung.

Now, the trolley 6 is placed in a slightly inclined state to wait for the coated metal tube V coming out from the extrusion target device l, but the lengths of the wires 7m and 7b are set to the lengths described above. For this reason, in this standby state, the coated metal tube V coming out of the extrusion target device 1 can easily pass through the darkness of the wires 7m and 7b suspended in a U-shape.

In addition, the trolley 6 waiting at a predetermined position on the rail 51 is also used for detection using an eddy current sensor in order to confirm that the end of the coated metal tube V passes through the midpoint between the suspended wire 7m and the wire 7b. A detector 4 is provided, and the detector 4
The probability that the V end of the metal pipe to be welded passes through the midpoint of the wire m
lTo operate one cylinder 5C at the same time, truck 6
is a horizontal spoon, and the coated metal tube V is preceded by a wire 7b.

The rear end is also covered by a coated metal tube V followed by 7 m of wire.
The tips of each are suspended.

After that, the trolley 6 with the coated metal tube V suspended thereon is moved forward by the driving force of the pinch rolls 3 that advance the metal tube W, and is placed on the extension line of the rail 5m, using the shirt method. It is transferred onto a forward rail 8 on which water cooling equipment is installed in parallel. From the upstream side of the advance rail 8#f, there is an upstream horizontal section 8m where the truck 6 is transferred from the rail 5a, and an upward slope g8 that slopes upward at an inclination angle of about 1°.
b. An intermediate horizontal portion 8c having a length sufficient for water cooling.
.

A descending slope part 8 that slopes downward with an inclination angle of about 2@
d and a downstream horizontal portion 8e corresponding to its most downstream end. Nine bogies 6Fi are transferred onto the upstream horizontal portion 8a of the advance rail 8, and as shown in FIG.
While suspending the front end and rear end of the pinch roll 3,
It is moved further forward by the driving force of , and moves to the intermediate horizontal portion 8C via the upwardly inclined portion 8b. In this state, the trolley 6 is lifted upward by the upward slope portion 8b compared to the case where it is placed on the upstream horizontal portion 8a, and is in good condition, and the coated metal pipe V is placed on the wire 7m. ,
This prevents accidents such as separation from 7b.

The trolley 6 on which the wires 7m and 7b are hung is sufficient to suspend the tip and rear end of the continuously conveyed coated metal pipe V, respectively, and the trolley 6 suspends the wires 7m and 7b. The coated metal tube V is conveyed while being suspended.

When the trolley 6 is further advanced while suspending the coated metal tube V, passing through the downward slope section 8d and reaching the downstream horizontal section 8c, the coated metal tube W, which has been cooled to an appropriate temperature, is removed from the carriage 6. It is detached from the suspended wires 7m and 7b and placed on a plurality of conveyor rolls 9 arranged at this position and downstream thereof. When the coated metal tube V is placed on the conveyor roll 9, the wire 7
m.

7bij Manually removed from the trolley 6, the coated metal pipe W
' is a trap so that it is transported to the subsequent process by the driving force of the conveyor roll 9.

Further, a hoist crane 10 is installed at a downstream horizontal portion 8c of the forward rail 8, and the hoist crane I
From OK, the wire 7!1゜7b is removed as described above, lifted up through the 7 hooks of the 9 bogie 6/fi, and transferred onto the reverse rail ll which is provided in parallel above the forward rail 8. After that, it is pushed back by an appropriate drive # to above the upstream horizontal portion 8 of the forward rail 8. Then, the trolley 6Fi is transferred onto the rail 5m of the trolley tilting device 5 by appropriate means, and the above-described operation is further repeated.

When carrying a nine-covered metal tube V that has been coated with tube heating using the equipment described above, in order to hold the coated metal tube V while it is cooling, the end of the tube that is to be cut off later is connected with a wire of 7 m, 7b, the lower part of the metal tube V to be cut will not come into contact with the conveyor roll 9 in a state where cooling is insufficient except for the tube end. Therefore, damages such as dents in the lower part of the metal tube due to the weight of the coated metal tube V itself, contact flaws with the conveyor 0-7L/9, and poor adhesion of the coating layer are avoided from occurring in the effective portion of the coated metal tube V. It becomes 0T ability to do.

In this embodiment, wires 7m and 7b are suspended from the trolley 6 as a method of holding the end of the coated metal tube V.
A method of suspending the coated metal pipe V was adopted, and a trolley 6 was installed in parallel above the forward rail 8 to return the trolley 6 to its original state after completing the conveyance of the coated metal pipe V. It was decided to adopt a method of pushing back on the backward rail ll, but as shown in Fig. 3, the covered metal tube V was covered using clamping tools 12m and 12b that move the end of the covered metal tube V in parallel up and down. Immediately after the treatment, the coated metal tube V is conveyed from the top and bottom by being held in the state s) shown by the broken line in the figure by running the clamping device 12 on the forward rail 13 as it is, and when the conveyance is completed, the coated metal tube V is is released from the clamping device 12ae12b (as shown by the solid line in the figure), and then the clamping device 12
is horizontally moved to the installation position of a backward rail 14 provided on the side of the forward rail 13 and parallel thereto, and on the backward rail 14, the clamping device 12 is moved in the direction opposite to the direction in which the coated metal tube V travels. It is also possible to adopt a method of running the vehicle and returning it to its original state.

As described in detail above, the present invention detects the end of the metal tube that should be cut off after the metal tube is conveyed while cooling it after being coated with tube heating, and while holding the end of the metal tube. Since the metal tube is transported, the effective part of the metal tube will not be damaged. Therefore, the present invention is highly effective in maintaining high quality when manufacturing a coated metal tube by applying a coating treatment that involves tube heating, such as a high adhesion type.

[Brief explanation of the drawing]

Fig. 1 is a schematic side view showing the equipment for carrying out the method of the present invention, Fig. 2 is a perspective view showing a coated metal pipe suspended from a trolley with 92 wires, and Fig. 3 The figure is a schematic diagram showing another embodiment of the method of the present invention. W... Metal tube V... Covered metal tube 1... Extrusion target device 3... Pinch roll 4... Detector 5.
... Hanging support starting device 6 ... Cart 7m, 7b ... Wire 9 ... Conveyor roll patent Applicant Sumitomo Metal Industries Co., Ltd. Agent Patent attorney Noboru Kono Figure 2 1F! 3 diagram

Claims (1)

[Claims] 1. Heating multiple metal tubes that are connected and conveyed in succession,
In the method of manufacturing a coated metal pipe by coating the outer surface thereof, detecting the end of the connecting pipe after the coating treatment, transporting the connecting pipe while holding the end, and cooling the coated metal pipe. A method of manufacturing a coated metal tube characterized by: