WO2003010356A1

WO2003010356A1 - Method for manufacturing pipe formed product and pipe formed product

Info

Publication number: WO2003010356A1
Application number: PCT/JP2002/007454
Authority: WO
Inventors: Kenichi Henmi
Original assignee: Sanoh Kogyo Kabushiki Kaisha
Priority date: 2001-07-23
Filing date: 2002-07-23
Publication date: 2003-02-06
Also published as: JP2003034877A

Abstract

A method for manufacturing a pipe formed product such as a fuel delivery pipe having a pipe-shaped portion capable of applying Ni plating also on the surface of brazing material at a weld part to prevent cracks in plating from occurring, characterized by comprising the steps of forming a complete-shaped body to form the pipe formed product by working and forming steel materials and applying non-electrolyte Ni plating to the complete-shaped body by immersing the complete- shaped body in Ni plating solution.

Description

Description Method for producing pipe molded product and pipe molded product

The present invention relates to a method for producing a pipe molded product and a pipe molded product, and more particularly to a method for producing a highly corrosion-resistant pipe molded product such as a fuel delivery pipe used for parts of an automobile, and a pipe molded product. Background art

Since fuel such as gasoline flows inside the fuel delivery pipe, if the inside is eroded by oxidation or the like, rust pieces and the like may be conveyed into the engine, which is not preferable. Therefore, high corrosion resistance is required inside the fuel delivery pipe.

When the fuel delivery pipe is molded using an aluminum material or the like, the aluminum material has strong corrosion resistance against oxidation and the like, so that the inside of the fuel delivery pipe does not need to be plated.

However, when a fuel delivery pipe is made of an iron material, it is necessary to plate the inside of the fuel delivery pipe to prevent oxidation and the like. When the fuel delivery pipe is made of an iron material, after forming the fuel delivery pipe, a complicated concave portion is formed inside the pipe, so that the entire inside of the fuel delivery pipe is uniformly formed. Plating is not easy.

Therefore, in the past, in the manufacture of fuel delivery pipes, an iron plate and a pipe were subjected to Ni plating in advance, followed by bending and welding to form a product shaped body. Then, the outer surface of the product is subjected to a printing process such as Zn or ZnNi, and then a chromate process. In this case, the inner surface of the fuel delivery pipe is subjected to Ni plating, and the outer surface thereof is subjected to plating such as Ni plating, Zn or ZnNi, and chromate treatment. In addition, in these plating processes, the electroless Ni plating process was not performed, and the electrolytic Ni plating process was performed. Conventionally, there has been a problem that the Ni plate is not applied to the cut surface because the cutting process or the like is performed on the iron plate material or the tube material which has been previously plated with Ni.

There was a problem that the Ni plating was not applied to the surface of the mouth material used during welding. ₍ If the Ni plating was thick, bending cracking could cause plating cracks. Gasoline may come into direct contact with the steel material on the side surfaces, and the Ni layer, which is a barrier layer, is interrupted on the outer side surface, resulting in a problem of reduced corrosion resistance.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a pipe molded product that solves the above-mentioned problems of the prior art and enables the manufacture of a tubular product such as a highly corrosion-resistant fuel delivery pipe.

In order to achieve the above object, the present invention relates to a method for producing a pipe molded product having a pipe-shaped portion, comprising: Forming; and dipping the completed shaped body in a Ni plating liquid to perform electroless Ni plating.

Further, the method is characterized by comprising, following the electroless Ni plating step, a step of applying a Zn plating or a Zn alloy plating, a step of performing a chromate treatment, and a step of performing an organic coating treatment.

Further, it is a pipe molded product having a pipe-shaped portion, and in a state where a completed shape to be the pipe molded product is formed, an electroless N formed on a surface of the completed shape is formed. It is characterized by having a Ni plating layer by i plating.

The Ni plating layer is formed on the inner surface and the outer surface of the completed shape, and the Zn formed on the Ni plating layer on the outer surface of the completed shape is formed. It is characterized by comprising a Zn plating layer formed by plating or a Zn alloy alloy, a chromate treatment layer formed on the Zn plating layer, and an organic coating treatment layer formed on the chromate treatment layer. And

The Ni plating layer is formed on an inner surface and an outer surface of the completed shape, and the Ni plating on the inner surface and the outer surface of the completed shape. A Zn plating layer formed on the plating layer by Zn plating or Zn alloy plating; a chromate treatment layer formed on the Zn plating layer; and an organic layer formed on the chromate treatment layer. And a coating treatment layer.

Further, the pipe molding is a fuel delivery pipe.

Further, the pipe molded product is characterized in that the pipe length is at least three times the pipe diameter.

In the above invention, the finished shape is formed by processing and forming the steel material, and the finished shape is subjected to the electroless Ni plating. Also, since it is not necessary to newly perform a bending process or the like, it is possible to eliminate the occurrence of cracks, and since there is no need to dispose electrodes, the inner surface of the pipe-shaped portion is not required. Also Ni plating can be applied. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a perspective view showing a fuel delivery pipe pipe as an example of a molded pipe.

FIG. 2 is a diagram showing a manufacturing process of a molded pipe.

FIG. 3 is a cross-sectional view showing the surface of the molded pipe. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a schematic configuration of a fuel delivery pipe 1 as an example of a tubular product. The fuel delivery pipe 1 includes a plurality of cylindrical pipes 2 and a long and thin connecting pipe 3 for connecting the pipes 2 to each other to feed and discharge fuel. The pipe part 2 is connected to the connecting pipe 3 like a branch pipe, and a branch part is formed at the connecting part of the connecting pipe 3 of the connecting pipe 3. Fuel is supplied from the B side and sent out to the A side.

Here, the tubular product targeted by the embodiment of the present invention has a longer length in the flow direction than the diameter of a pipe forming a fluid flow path, such as a fuel delivery pipe 1, for example. , Whose length in the channel direction is at least 3 times longer than the pipe diameter It is. If the length in the direction of the flow path is three times or more longer than the diameter of the pipe in this way, when the product Ni (electroformed Ni) is subjected to electrolytic Ni plating via a pair of electrodes, Even if one electrode is attached to the product shape and an electric field is applied, the electric field does not spread sufficiently to the back of the tube due to the shielding effect of the cylindrical conductor. For this reason, the electrolytic plating reaction occurs only in a length range of about 1.5 times the pipe diameter from the pipe end, and it is impossible to perform uniform plating on the inner wall surface of the product shape without unevenness. . Here, the diameter of the pipe refers to the thickness of the cylindrical body such as a rectangular parallelepiped.

When manufacturing the fuel delivery pipe 1, as shown in FIG. 2, first, in ST 1, an iron plate material and an iron tube material are cut and formed into a predetermined shape according to a known processing method. The formed parts are connected to each other by welding to finish the finished product.

Next, surface treatment of the product shape body is performed in ST2. In this surface treatment, a product shape body that has been completed in shape to become the fuel delivery pipe 1 is placed in a predetermined plating solution tank, and electroless Ni plating is performed by a known method. The electroless Ni plating is a plating performed using, for example, a Ni—P alloy. The product shape (finished shape) is rotated in the plating liquid tank or the plating liquid in the plating liquid tank is stirred so that the Ni plating liquid flows into the inside of the product shape. In this case, since the Ni plating is an electroless plating, it is not necessary to pass a current through the electrode, and the uniform distribution is achieved simply by applying a mechanical relative movement between the Ni plating liquid and the product. It is possible to apply the Ni plating without. Then, the Ni mask is applied to both the outer surface and the inner surface of the product shape body.

Next, in ST 3, mainly for the purpose of surface treatment of the outer surface of the product shape, after the electroless Ni plating, an additional Zn alloy alloy or Z is added to protect the Ni plating layer. Perform n Meseki. Then, a chromate treatment is performed as a final surface treatment, and a surface treatment for forming an organic film on the surface is further performed as necessary.

As a result, while the Ni surface is applied to the inner surface of the product shape, the Ni surface, the Zn alloy plating or Zn surface, and the chromate treatment are applied to the outer surface of the product shape. An organic coating process is performed. Next, in ST4, post-processing of the surface treatment is performed to obtain a fuel delino linophil 1 as a finished product.

As described above, according to the present embodiment, after a shape-completed product shape is processed and finished with a steel material, the product shape is subjected to electroless Ni plating. Ni plating can also be applied to the surface of the brazing material, and it is not necessary to perform new bending, etc., so that cracking does not occur even when the thickness of the Ni plating is large. Gasoline can be prevented from directly touching the steel material inside, and the corrosion resistance is reduced on the outer surface because the Ni layer, which is the barrier layer, is interrupted. In addition, since the Ni plating is an electroless plating, by performing a mechanical relative movement between the Ni plating liquid and the product shape without disposing an electrode, Inner surface of product It can be subjected to a uniform dark circles without N i plated.

Further, in addition to the electroless Ni plating, a Zn-based alloy plating or Zn plating, a chromate treatment, and an organic coating treatment can further enhance corrosion resistance against an external environment. As shown in FIG. 3, the pipe molded product is composed of an electroless Ni plating Ni layer 11 formed on the outer surface and the inner surface of the steel material 10, and a Ni plating layer 11 formed on the Ni material. The Zn plating layer 12 formed by the formed Zn plating or Zn alloy alloy, the chromate treatment layer 13 formed on the Zn plating layer 12, and the chromate treatment layer 13 formed on the Zn plating layer 13 And an organic coating treatment layer 14 formed.

In addition to the electroless Ni plating, the outer surface of the product is treated with Zn alloy plating or Zn plating, chromate treatment, and organic coating treatment only on the outer surface of the product. Performance can be efficiently enhanced. In this case, the molded pipe is provided with a Ni plating layer 11 made of an electroless Ni plating on the inner surface of the steel 10 and a Ni plating made of the electroless Ni plating on the outer surface of the steel 10. The print layer 11, the Zn print layer 12 formed on the Ni print layer 11 by the Zn print or Zn alloy print, and the Zn print layer 12 formed on the Zn print layer 12. It has a chromate treatment layer 13 and an organic coating treatment layer 14 formed on the chromate treatment layer 13. In the above description, the pipe molded product is not limited to a tubular one such as a cylindrical tube, but may be any one having a cavity (dent) formed therein. It may have openings at both ends.

Further, the fuel delivery pipe 1 is taken as an example of the high corrosion resistant pipe, but the high corrosion resistance pipe is not limited to this, and any pipe having a recess therein may be used. Further, the fuel delivery pipe is not limited to the cylindrical pipe shown in FIG. 1, but may be formed in a rectangular parallelepiped by sheet metal and have openings at both ends.

The steel material may be iron or an alloy of iron and another metal as long as it is an iron material that corrodes when it comes into direct contact with gasoline or the like.

Further, the Zn plating may be a Zn alloy or a plating of Zn metal. As described above, according to the configuration of the present invention, a completed shape is formed by processing and forming a steel material, and the completed shape is subjected to electroless Ni plating. Things can be manufactured. Further, by forming a Zn plating layer, a chromate treatment layer, and an organic coating treatment layer on the electroless Ni plating Ni plating layer, a highly corrosion resistant pipe molded product can be supplied.

Claims

The scope of the claims

1. A method for manufacturing a pipe molded product having a pipe-shaped portion, wherein a step of processing and forming a steel material to form a completed molded product to be a pipe molded product; A method of electroless Ni plating by dipping in a plating liquid.

2. Following the step of electroless Ni plating, a step of applying a Zn plating or Zn alloy plating, a step of performing a chromate treatment, and a step of performing an organic coating treatment are provided.

The method for producing a pipe molded product according to claim 1, wherein:

3. The molded pipe is a fuel delivery pipe

The method for producing a pipe molded product according to claim 1, wherein:

4. The method for producing a molded pipe according to claim 1, wherein the length of the molded pipe is at least three times the diameter of the pipe.

5. A pipe molded product having a pipe-shaped portion,

In the state where the completed shape to be formed into the pipe molded product is formed, a Ni plating layer formed by electroless Ni plating formed on the surface of the completed shape is provided.

A molded pipe product characterized by the above-mentioned.

6. The Ni plating layer is formed on an inner surface and an outer surface of the completed shape body,

A Zn plating layer formed on the Ni plating layer on the outer surface of the completed shaped body by Zn plating or Zn plating alloy plating; and a chromate formed on the Zn plating layer. 6. The molded pipe according to claim 5, comprising a treatment layer and an organic coating treatment layer formed on the chromate treatment layer.

7. The Ni plating layer is formed on an inner surface and an outer surface of the completed shape body,

A Zn plating layer or a Zn plating alloy layer formed on the Ni plating layer on the inner surface and the outer surface of the completed shape body; and a Zn plating layer formed on the Zn plating layer. Chromated layer and the 6. The molded pipe according to claim 5, comprising a formed organic film treatment layer. .

8. The molded pipe according to claim 5, wherein the molded pipe is a fuel delivery pipe.

9. The molded pipe according to claim 5, wherein the length of the molded pipe is at least three times the diameter of the pipe.