JPS5919146A - Manufacture of fluid transport pipe - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a transport pipe used for relatively low pressure fluid transport such as lubricating oil transport or working pneumatic transport to pneumatic machines.

Steel pipes, which are easy to bend and deform and are easy to cut, and are easy to install, have been commonly used for such fluid transportation, but they are heavy and expensive, and when bent with a small radius of curvature, the bent part collapses flat. There was a problem in that the cross-sectional area of the pole 0111 became smaller and it was difficult to restore the flattened part due to plastic deformation.

Focusing on this fact, the present invention has been developed to provide a pipe that is easy to bend and cut, comparable to or even easier to handle than copper pipes, yet lightweight and relatively inexpensive (can be manufactured locally, and has a flat surface). The purpose of the present invention is to provide a method for manufacturing such a transport pipe that can be easily restored after being crushed.

The details will be explained below based on FIG. 1.

The transport pipe 1 to which the present invention is applied basically consists of a thin metal inner pipe 2 and a thick synthetic resin film Nll3 covering the outer periphery of the metal inner pipe 2.
It consists of.

To explain one example of this manufacturing method, first, a synthetic resin 1 such as polyethylene is thinly applied to both the front and back surfaces of a thin blank plate made of aluminum or an aluminum alloy to form the films 4 and 5.

Next, the blank plate is passed through a slitter to obtain a 11ν plate with a constant width. Then, the 11th plate is bent parallel to its elongated direction and carved into a tubular thin metal inner tube 2 with edges 2a and 2b overlapping inside and outside. Finally, the outer circumference of the metal inner tube 2 is
An elastically deformable synthetic resin coating 3 made of the same material as this is coated on the outer periphery of the metal inner tube 14 to a thickness smaller than that of the metal inner tube 2.

The transport pipe 1 thus formed can be easily cut with a knife or the like, and can also be freely bent and held in its shape. Then, when bent, the metal inner tube 2
It is maintained in its bent state by plastic deformation, and the thick synthetic resin coating 30 has a moderate elastic force.

Due to the change in the circumferential length of the metal inner tube 2 due to some relative displacement between the overlapping edges 2a and 2b of the metal inner tube 2, the bent portion is prevented from becoming unduly flat.

In addition, the inner circumferential film 5 of the metal inner tube 2 makes the inside of the inner tube 2 excellent in corrosion protection and chemical resistance, and the close contact between the inner circumferential film 5 and the outer circumferential film 4 allows the space between the overlapping edges 2a and 2b to be improved. A sealing effect can be obtained. Further, the thick synthetic resin coating 3 is integrally formed with the outer circumferential membrane 4 of the metal inner tube 2 in a close contact manner.

Note that 1 synthetic resin films 4 and 5 are applied not only to both the front and back sides of the band but also to the cut end surfaces of the edges 2a and 2b by passing the band through a synthetic resin solution bath after obtaining the band from the raw board. It may also be formed by coating.

The end of this fluid transport pipe 1 is inserted into and externally fitted into a connecting pipe section 7 provided in a hard plastic plastic or metal joint 1-6, and a collar 8 made of plastic plastic is attached to the outer periphery of the insertion part. By fitting the nut 9 into the joint 6 and tightening it from its outer periphery, the tapered cam surface 10 of the nut 9 tightens and deforms the collar 8 toward the axis, thereby connecting the tip of the transport pipe 1 to the connecting pipe section. 7 and fix it by pressure. Then, this joint 6 is used by being connected to a joint of the target device or a relay joint.

As explained above, according to the present invention, a fluid transport pipe consisting of a thin-walled metal inner pipe 2 made of aluminum or aluminum alloy and a thick-walled synthetic resin coating 3 is obtained, and this transport pipe can be bent and cut like a copper pipe. It is equally or even easier to perform, and can be made lighter and cheaper than IPI pipes. In addition, the metal inner tube 2 is formed by bending a band-shaped aluminum or aluminum alloy plate into a tubular shape and forming a thin-walled tube whose circumferential length can be slightly changed by overlapping both end edges 2a and 2b. Since it is covered with the synthetic resin coating 3, the cross section will not become extremely flat like a steel pipe even if it is bent with a small radius of curvature, and even if it is slightly flattened, the elasticity of the synthetic resin coating 3 will change when it is stretched after bending. It can easily be restored to a circular shape by the restoring force, and is extremely effective in terms of its function as a fluid transport pipe.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a transport pipe obtained according to the present invention, FIG. 2 is an enlarged cross-sectional view of the transport pipe, and FIG. 3 is a cross-sectional view of a joint attachment part. 2...Metal inner tube. 3...Synthetic resin coating. 4.5...Synthetic resin membrane.

Claims (1)

[Claims] (1) A step of forming a thin synthetic resin film on both the front and back sides of a strip made of aluminum or aluminum alloy, bending the strip with the synthetic resin film formed into a tubular shape, and overlapping the edges of the strip. A fluid transport tube comprising the steps of: molding a thin metal inner tube by forming a thin metal inner tube; and forming an elastically deformable synthetic resin coating that is thicker than the thickness of the core inner tube on the outer periphery of the outer synthetic resin membrane of the inner tube. manufacturing method.