CN1123203A

CN1123203A - Mathod for making double-layer metal tube

Info

Publication number: CN1123203A
Application number: CN 94118477
Authority: CN
Inventors: 林荣灿
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-11-16
Filing date: 1994-11-16
Publication date: 1996-05-29

Abstract

The mfg. method involves cutting one first metallic tube piece and one second metallic tube piece respectively. The inside diameter of second metallic tube piece is greater than outside diameter of first metallic tube piece. Both metallic tube pieces are respectively fixed. A forming device is forcedly passed through the interior of first metallic tube piece, and the outside surface of first metallic tube piece is tightly closed to the inside surface of second metallic tube piece. USE-can be used for manufacturing double-layer metallic tube piece.

Description

The manufacture method of bimetal pipe

The present invention relates to a kind of method for metal working, particularly at the manufacture method of bimetal pipe.

Some metal material, for example: stainless steel, copper, aluminium etc., its unit price is quite high, so, if the material that these are relatively more expensive is directly brought when making pipe fitting, the cost and the price of the industrial product that adopts this stainless steel tube, copper pipe, aluminum pipe are higher with causing, under certain conditions and be not inconsistent economic principle.

The object of the present invention is to provide a kind of manufacture method of bimetal pipe, the internal layer of the bimetallic tube that it is made is a carbon steel material, outer then can be expensive material such as stainless steel, copper, aluminium, then can be cheaply more many under the condition of equal pipe wall thickness than individual layer stainless steel tube, copper pipe, aluminum pipe.

Below will provide preferred embodiment in conjunction with the accompanying drawings technology contents of the present invention to be given a detailed account.

Fig. 1 is that first pipe fitting does not insert the interior situation of second pipe fitting as yet.

Fig. 2 is that first pipe fitting inserts the interior situation of second pipe fitting.

Fig. 3 mainly is the schematic diagram that shows shaped device 30.

Fig. 4 is a product structure schematic diagram of the present invention.

At first, moulding also cuts first pipe fitting 10 of a suitable length, and the material of this first pipe fitting 10 can be carbon steel.

Continue it, in addition moulding and cut second pipe fitting 20 that gives measured length, the material of this second pipe fitting 20 can be stainless steel, copper or aluminium etc., the internal diameter of this second pipe fitting 20 is slightly larger than the external diameter of this first pipe fitting 10, the pipe wall thickness t2 of this second pipe fitting 20 approximately be first pipe fitting 10 pipe wall thickness 1/3rd to the sixth, such as, when the pipe wall thickness of first pipe fitting 10 be 1.6cm (centimetre) time, the pipe wall thickness of this second pipe fitting 20 is about 0.5cm.

Then, this second pipe fitting 20 is fixed, as shown in Figure 1 and Figure 2 this first pipe fitting 10 is inserted in these second pipe fittings 20 again, and the front end that makes this first pipe fitting 10 is by block.

Then, make a shaped device 30 pass through first pipe fitting 10 by force, and go out, because the front end of first pipe fitting 10 is by block, so unlikely being pushed goes forth by the front end of first pipe fitting 10 from rear end 12 beginnings of carbon steel pipe 10; As shown in Figure 3, the hardness of the material that this shaped device 30 is adopted is than the material hardness height of first pipe fitting 10, it has a large-diameter portion 32 that is positioned at the guide shaft portion 31 of leading portion and is positioned at back segment, the external diameter of this guide shaft portion 31 is slightly less than the internal diameter of this first pipe fitting 10, the outer radial periphery face of this large-diameter portion 32 is external convex arc shape, its largest circumference outside dimension than " internal diameter of second pipe fitting 20 " deduct " external diameter of first pipe fitting 10 " add " internal diameter of first pipe fitting 10 " also slightly bigger, this guide shaft portion 31 is entered in first pipe fitting 10 this shaped device 30 smoothly, this large-diameter portion 32 then enlarges the caliber of this first pipe fitting 10, be close to the internal face of this second pipe fitting 20 as shown in Figure 4 with the outer peripheral face that makes this first pipe fitting 10, and become the pair of lamina pipe.

The very thin thickness that focuses on second pipe fitting 20 of its skin of the present invention is an example with the copper pipe, can possess the color characteristic attractive in appearance and antirust of copper, and compare with the individual layer copper pipe of same thickness, can significantly reduce manufacturing cost, and promote the competitiveness in market, very have a value on the industry.

The bimetallic tube that is coated on carbon steel pipe as for stainless steel tube then can be applicable to the place of an a little abrasion performance, this is as saying: be installed with a standpipe below the seat cushion of bicycle, this standpipe is plugged in the middle slope tube top section of vehicle frame, the regulating part of adjusting slope tube top in this just can more be pressed into standpipe or pull out elongated, adjust the height of seat cushion whereby, with the height that adapts to the cyclist or ride appearance, and known base riser is to be material with the carbon steel pipe, plate one deck chromium on this carbon steel pipe surface, to reach wear-resisting effect,, the thickness of coating is restriction to some extent but, at most be plated to 4 μ m (micron), when if the thickness of coating reaches 5 μ m (micron), the attached outstanding power of coating is promptly very poor, promptly begin to occur peeling off phenomenon after using length, therefore so thin coating is after standpipe is spurred repeatedly up and down, the standpipe surface promptly presents the noticeable wear phenomenon, in the near future carbon steel pipe promptly can begin corrosion because of exposing to wind and rain, if attempt directly makes carbon steel pipe into whole stainless steel tube, material cost is but up to eight of carbon steel pipe, nine times, but though abrasion performance, but increase the cost of bicycle on foot, be not inconsistent economic principle, the present invention just can solve this bottleneck problem.

Claims

1. the manufacture method of a bimetal pipe is characterized in that, it includes following step:

(a) moulding and cut first metal tube of a suitable length;

(b) moulding and cut second metal tube that gives measured length, the internal diameter of this second metal tube is slightly larger than the external diameter of this first metal tube, and the pipe wall thickness of this first metal tube is that giving of the second metal tube pipe wall thickness decided multiple;

(c) this second metal tube is fixed;

(d) this first metal tube is inserted in this second metal tube, and the front end of this first metal tube is given block;

(e) make a shaped device begin to make a forcible entry into from the rear end of this first metal tube, and the front end by first metal tube, the hardness of the material that this shaped device adopted is than the material hardness height of first metal tube, it has one and is positioned at the guide shaft portion of leading portion and the large-diameter portion that is positioned at back segment, the external diameter of this guide shaft portion is slightly less than the internal diameter of this first metal tube, the outer radial periphery face of this large-diameter portion is external convex arc shape, and the external diameter that the internal diameter that its maximum radial circumference external diameter is a bit larger tham second metal tube deducts first metal tube is added the internal diameter of first metal tube.

2. the method for claim 1 is characterized in that: this first pipe fitting employing carbon steel, second pipe fitting employing stainless steel.

3. the method for claim 1 is characterized in that: this first pipe fitting employing carbon steel, second pipe fitting employing copper.

4. the method for claim 1 is characterized in that: this first pipe fitting employing carbon steel, second pipe fitting employing aluminium.

5. the method for claim 1 is characterized in that: the wall thickness of this second pipe fitting approximately be first pipe fitting wall thickness 1/3rd to the sixth.