JPS59169635A - Manufacture of gas cylinder - Google Patents

Abstract

PURPOSE:To obtain a product of high quality by cold drawing of a blank in making the body of a cylinder by drawing a blank blanked from a steel plate by trimming the peripheral of opening in the course of working. CONSTITUTION:After annealing a blank 1 blanked from a steel plate, the blank is worked successively to a cylindrical body 2a-2c by drawing of the first - third processes. Then, the periphery of the flange part 3 of the cylindrical body 2c is removed by trimming and semimanufactured product 4 is formed. Thus, generation of cracks from the periphery of flange part is eradicated, and cracking of the part is prevented by succeeding drawing work. Works similar to the above are made on the semimanufactured product 4 by drawing works of the fifth - eighth processes to obtain a cylindrical body 5d. The outer periphery of the flange part 6 is trimmed for sizing and the second semimanufactured product 7 is obtained. Further, the spread of opening of the semimanufactured product 7 is corrected and a cylinder 8 in which the opening part is made linear is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of manufacturing a gas cylinder, and more particularly to a method of manufacturing a gas cylinder by cold drawing from a steel plate.

The gas cylinder is made of cold rolled steel plate (SPC-) according to JIS standards.
E, 5PC-EN), but non-disposable types do not use the above steel plate, and have a higher Mn content than these materials.
It is made of special steel containing a lot of carbon. By the way, when many drawing processes are performed, such as for gas cylinders, cracks occur in the vertical walls and flange portions of the product due to work hardening and age hardening, making it virtually impossible to manufacture by drawing processes. For this reason, in the past, pipe materials were used, the pipes were heated, and one end of the pipes was melted and integrated by roll forming while hot. In addition, the other end is heated in the same way, and the cap is formed in the hot state.
They were manufacturing gas cylinders.

The present invention has been made in view of these conventional circumstances, and includes making a blank from a steel plate by blanking processing,
The object of the present invention is to provide a method of manufacturing a gas cylinder by annealing the blank to form a spheroid and drawing the annealed blank.

In order to achieve the above object, the present invention performs cold drawing on a blank, but in order to prevent cracks from occurring at the flange due to work hardening and work strain, trimming is performed during processing to prevent the flange from forming. By removing small cracks that occur in the parts and continuing the drawing process again, we are able to obtain high-quality products.

In addition, the molding of the mouthpiece is done using the same process as before.
I'll get two. Furthermore, in order to minimize the phenomenon that the thickness of the top plate becomes thinner, which is a characteristic of gas cylinders,
It is important to determine the drawing ratio and the layout shape.

Next, a concrete example of carrying out the method of the present invention will be explained with reference to illustrated embodiments.

Blank 1 punched from a steel plate is annealed and then 1fl
From this, the cylindrical bodies 2a, 2b, and 2c are sequentially processed in the third drawing process, and then a trimming process is performed to remove the periphery of the flange portion 3 of the cylindrical body 2C obtained in the third drawing process to obtain a semi-finished product. form 4. This prevents cracking from occurring around the flange portion, and prevents cracking in that portion during subsequent drawing processing.

Next, the blank product 4 is processed again into cylindrical bodies 5a, 5b, and 5C by drawing in the fifth to eighth steps, and then drawn to round the bottom wall of the cylinder to form a cylindrical body 5d. do.

Further, the outer edge of the flange portion 6 of the cylindrical body 5d is trimmed to determine the dimensions, and a second blank 7 is obtained.

Furthermore, in the next step, the enlargement of the opening of the second blank 7 is corrected, and the cylinder body 8 is formed into a straight line.

In this example, the diameter of the blank was 270 mm, but the outer diameter of the cylinder body after the first to tenth steps was 50 mm.
It has a cylindrical shape with a diameter of 8 mm and a height of 300 to 305 mm.

The opening of the cylinder body 8 is then formed into a mouthpiece by a necking process (not shown) to form a cylinder.

As explained below, in the present invention, trimming is performed during the drawing process to remove fine cracks that appear around the opening, making it possible to draw the blank in the cold, thereby increasing productivity. It has the effects of reducing labor costs, reducing equipment costs, and improving quality.

[Brief explanation of the drawing]

Figure 1 is a plan view of the blank, Figure 2 is a process diagram for obtaining a semi-finished product, Figure 3 is a process diagram for obtaining a second semi-finished product, and Figure 4 is a cross-sectional view of the cylinder body. . l... Blank 2.5... Cylindrical body 8.
...Cylinder body 4.7...Semi-finished product patent applicant AIDA Engineering Co., Ltd. Agent Patent attorney Kiyoshi Nakayama (and one other person) Figure 1 Figure 2 C (A) (B) (C) (D)

Claims (1)

[Claims] A method for producing a gas cylinder, in which a blank punched from a steel plate is formed into a cylindrical semi-finished product by drawing, the periphery of the opening is trimmed during processing, and the cylinder body is formed by drawing again.