CN112264771A

CN112264771A - Manufacturing process of pressure vessel cylinder

Info

Publication number: CN112264771A
Application number: CN202011392995.2A
Authority: CN
Inventors: 王红新; 张会明; 方金艳; 魏目青; 张超; 闫黎明
Original assignee: Shandong Binglun Haizhuo Hydrogen Technology Research Institute Co ltd; Yantai Moon Compressor Co ltd
Current assignee: Shandong Binglun Haizhuo Hydrogen Technology Research Institute Co ltd; Yantai Moon Compressor Co ltd
Priority date: 2020-12-03
Filing date: 2020-12-03
Publication date: 2021-01-26

Abstract

The invention discloses a pressure vessel barrel manufacturing process, which mainly comprises the steps of carrying out incomplete cutting blanking on a plurality of openings which have larger diameters, are close to the edges of the barrel or welding seams and are adjacent in a local range and influence the rolling quality of the barrel, and cutting off joints after rounding the barrel, so that the stress concentration at the openings during rolling of the barrel can be obviously reduced, the structural strength and the continuity of the openings are improved, the roundness of the barrel is improved, and the rolling quality of the barrel is ensured.

Description

Manufacturing process of pressure vessel cylinder

Technical Field

The invention relates to a manufacturing process of a pressure vessel cylinder.

Background

Pressure vessel equipment is widely applied to various industries, and a cylinder body formed by rolling a steel plate is one of important parts in the pressure vessel equipment. In order to facilitate the installation and welding of the connecting pipe on the steel plate cylinder, corresponding holes need to be formed in the cylinder body.

Under traditional operation mode, the production process of barrel includes processes such as steel sheet unloading, sandblast, steel sheet book system, longitudinal joint welding, barrel school circle, trompil setting-out, manual trompil, trompil are polished. With the application of advanced blanking technologies such as numerical control plasma cutting, numerical control flame cutting and the like, the tapping operation flow is simplified, and the tapping operation flow comprises the working procedures of steel plate pre-tapping blanking, steel plate rolling, longitudinal seam welding, cylinder body rounding and the like.

The pre-hole-opening blanking refers to that a three-dimensional model of the cylinder body is unfolded through three-dimensional software, and holes are directly cut out through numerical control equipment during blanking. The pre-tapping blanking has the advantages of simplifying the production flow of the cylinder body, improving the production efficiency, reducing the working strength of workers and the like, but after pre-tapping, the tapping generates stress concentration in a local range in the steel plate rolling process, and particularly, when the diameter of the tapping is larger, the structural continuity of a nearby area is lost, the strength and stability of the cylinder are affected, and the cylinder body cannot be rolled or the out-of-roundness of the cylinder body is out of tolerance after rolling.

Chinese utility model patent with publication number CN201618558U discloses a "reinforcing structure with large opening for thin-wall pressure vessel". The Chinese utility model with the publication number of CN203202482U discloses a deformation-preventing structure for welding a thin-wall cylinder and a large-diameter dense calandria. The Chinese patent application with the application publication number of CN110871300A discloses a dense hole opening method and a circular anti-deformation support for a large-diameter thin-wall sleeve. The technical means for solving the out-of-roundness problem through the published technologies are that a reinforcing device is arranged at the position of the hole, and the defect of complex operation exists generally.

The application publication number of the invention is CN104889581A, which discloses a deformation preventing process for welding dense connecting pipes on a thin-wall cylinder, and the process also adopts a technical means of arranging a reinforcing device at the position of a hole, in addition, the process adopts a mode that holes are formed on the cylinder at intervals in a crossed mode, and the holes are cut discontinuously and locally, and the premise is that the holes are formed on the cylinder, and the cylinder is processed and rolled during the hole forming, so that the operation is complex, and the technical problems are difficult to fundamentally solve.

Disclosure of Invention

The invention aims to solve the technical problem of providing a pressure vessel cylinder manufacturing process, which reduces stress concentration when a cylinder steel plate with a pre-opening hole is rolled and avoids the problems that the cylinder cannot be rolled or the cylinder is not circular too much after being rolled due to the opening under special conditions.

The technical scheme of the invention is as follows:

a manufacturing process of a pressure vessel cylinder is characterized by comprising the following steps:

step one, drawing a track line: drawing an opening outer edge trajectory line on the front surface of the pressure container cylinder flat plate, wherein the opening outer edge trajectory line consists of a pre-cutting trajectory line and a to-be-cut trajectory line, the to-be-cut trajectory lines are at least one pair, and two of each pair of to-be-cut trajectory lines are opposite to each other; for non-orthogonal circular holes: drawing an auxiliary track line of the auxiliary hole on the inner side of the track line to be cut, and enabling the outermost point of the auxiliary track line to coincide with the central point of the corresponding track line to be cut;

step two, pre-drilling holes: cutting along the pre-cutting trajectory line to connect the plate material at the opening position with the periphery thereof depending on the trajectory line part to be cut; cutting auxiliary holes along the auxiliary track line for the non-orthogonal circular holes;

thirdly, sand blasting: removing oxide skin and iron rust on the surface of the flat plate;

step four, rolling: rolling the barrel flat plate into a barrel shape;

fifthly, welding longitudinal seams;

sixthly, rounding;

seventh step, cutting ribs: for the orthogonal round hole, drawing a circle along the pre-cut seam formed by the pre-opening hole to form a secondary cutting line, and then cutting and removing the plate material at the opening part along the secondary cutting line; and for the non-orthogonal round holes, connecting the outermost side of the adjacent pre-cutting seams and the auxiliary holes to form an arc line as a secondary cutting line, and then cutting and removing the plate at the opening part along the secondary cutting line.

Preferably, the design method of the outer edge trajectory line of the opening hole comprises the following steps: and importing a three-dimensional model of the cylinder into the three-dimensional software for expansion, and importing the expanded model into the layout CAD software.

On the premise of meeting the requirement of opening holes, the size of the auxiliary hole is as small as possible.

A flaw detection step may be further provided between the sixth step and the seventh step.

And a polishing step after cutting the ribs can be further included.

Compared with the prior art, the invention has the beneficial effects that:

firstly, stress concentration at the opening part can be reduced when the barrel is rolled through incomplete cutting, the structural strength and the continuity of the opening part are improved, and the rolling quality of the barrel is ensured.

The invention integrates the two procedures of blanking and hole opening into a whole, simplifies the whole process of cylinder processing, reduces the difficulty of post hole opening (secondary hole opening), and improves the cleanliness of the cylinder.

Drawings

FIG. 1 is a schematic view of a cylinder before rib cutting (orthogonal holes) according to an embodiment of the present invention.

FIG. 2 is a schematic view of a second cylinder before rib cutting (orthogonal hole) according to an embodiment of the present invention.

FIG. 3 is a schematic view of a three-cylinder body before rib cutting (eccentric hole) according to an embodiment of the present invention.

Detailed Description

The invention is further illustrated by the following examples and figures.

The embodiment of the manufacturing process of the pressure vessel cylinder body comprises the following steps of:

step one, drawing a track line: drawing an opening outer edge trajectory line on the front surface (namely the outer side surface of the cylinder body) of the pressure container cylinder body flat plate material, wherein the opening outer edge trajectory line consists of at least one pair (two) of pre-cutting trajectory lines and to-be-cut trajectory lines, and the two to-be-cut trajectory lines of each pair are opposite to each other. For orthogonal circular holes: the two opposite directions of each pair of the to-be-cut track lines mean that the midpoint of the two track lines continuously passes through the center of a circle. For non-orthogonal circular holes: the two mutually opposite directions of each pair of to-be-cut track lines mean that the midpoints of the two track lines continuously pass through the center of a circle and the projection line segments of the two track lines in the horizontal direction are superposed. In addition, for non-orthogonal circular holes: and drawing an auxiliary track line of the auxiliary hole on the inner side of the track line to be cut, and enabling the outermost point of the auxiliary track line to coincide with the central point of the corresponding track line to be cut. The auxiliary holes are used for confirming the vertex positions of the connecting positions of the incomplete opening holes of the asymmetric holes.

The size design of the auxiliary hole depends on the thickness of the plate and the precision of cutting equipment, and the size of the auxiliary hole is as small as possible on the premise of meeting the requirement of hole opening.

Examples of the trajectory line design means are: and importing a three-dimensional model of the cylinder into the three-dimensional software for expansion, and importing the expanded model into the layout CAD software.

Step two, pre-drilling holes: cutting along the pre-cutting track line to connect the plate material at the opening position with the periphery thereof depending on the position of the track line to be cut.

For non-orthogonal circular holes: and cutting the auxiliary hole along the auxiliary track line.

Thirdly, sand blasting: and removing oxide skin and iron rust on the surface of the flat plate.

Step four, rolling: and rolling the barrel flat plate into a barrel shape.

And fifthly, welding longitudinal seams.

And sixthly, correcting the circle. And (4) according to the material condition and the processing technology requirement, a flaw detection step can be set after rounding.

Seventh step, cutting ribs:

referring to fig. 1 and 2, for orthogonal circular holes, a circle is drawn along a precut 1 formed by pre-drilling to form a secondary cutting line 2, and then the panel blank at the drilled part is cut and removed along the secondary cutting line 2.

Referring to fig. 3, for non-orthogonal circular holes, the outermost side of the connecting adjacent precut 1 and auxiliary hole 3 is drawn with an arc line as a secondary cutting line 2, and then the plate material at the open hole is cut and removed along the secondary cutting line 2.

Eighth, grinding: and polishing the welding seam and the opening edge.

Example one

As shown in fig. 1, the present embodiment relates to the opening of orthogonal circular holes.

And incomplete cutting is carried out along the left-right symmetry direction of the cylinder body in the pre-hole opening process.

Example two

As shown in fig. 2, the present embodiment relates to the opening of another orthogonal circular hole.

When pre-drilling holes, the holes are symmetrically and incompletely cut along the circumferential direction of the cylinder body up, down, left and right.

EXAMPLE III

As shown in fig. 3, the present embodiment relates to the opening of non-orthogonal circular holes.

And cutting an auxiliary hole 3 for confirming the vertex position of the connecting part of the eccentric hole during pre-drilling.

The following is a roundness comparative example of two perforated cylinders made of the same cylinder specification and material.

The examples in table 1 are for orthogonal hole incomplete cut blanks of the invention and the comparative examples are for orthogonal hole complete cut blanks. And respectively unfolding the cylinder models in three-dimensional software and respectively guiding the cylinder models into layout CAD software. In the embodiment, holes are drilled for carrying out vertical symmetrical incomplete cutting, and the total length is kept to be 120 mm; the comparative example was completely vented.

TABLE 1

Name (R)	Examples	Comparative examples
			Diameter of cylinder	800mm	800mm
Thickness of cylinder	10mm	10mm
			Length of cylinder	300mm	300mm
Diameter of opening	φ150mm	φ150mm
			Hole-opening mode	The upper part and the lower part are symmetrical and incompletely cut, and the total length is 120mm	Complete cutting

And rolling, longitudinally welding and rounding after blanking. And cutting off the joints in the embodiment after rounding.

And then, measuring the out-of-roundness of the cylinder at the position of the opening and the periphery of the opening by using a standard clamping plate and a feeler gauge, wherein the measurement results are shown in the table 2.

TABLE 2

Name (R)	Examples	Comparative examples
			Maximum cylinder out-of-roundness/mm	2.6	5.2

It can be seen from table 2 that the present invention is effective in solving the problem of out-of-roundness of the cylinder.

The process of the invention is particularly suitable for the opening of the cylinder body at the following special positions and sizes: in the first type, the diameter DN is more than or equal to 93 mm; in the second category, the aperture DN within 200mm from the edge of the cylinder or the edge of the welding seam is not less than 60 mm; and in the third category, the nearest distance between the cutting seams of adjacent holes is less than 100mm, and the aperture DN is more than or equal to 60 mm.

Claims

1. A manufacturing process of a pressure vessel cylinder is characterized by comprising the following steps:

step four, rolling: rolling the barrel flat plate into a barrel shape;

fifthly, welding longitudinal seams;

sixthly, rounding;

seventh step, cutting ribs: for the orthogonal round hole, drawing a circle along the pre-cut seam (1) formed by pre-opening to form a secondary cutting line (2), and then cutting and removing the plate material at the opening along the secondary cutting line (2); for the non-orthogonal round holes, the outermost side of the connecting adjacent precutting seams (1) and the auxiliary holes (3) draws an arc line to serve as a secondary cutting line (2), and then the plate materials at the opening part are cut and removed along the secondary cutting line (2).

2. The process for fabricating a cylinder for a pressure vessel according to claim 1, wherein the design method of the outer edge trajectory of the opening comprises: and importing a three-dimensional model of the cylinder into the three-dimensional software for expansion, and importing the expanded model into the layout CAD software.

3. A process for making a cylinder for a pressure vessel according to claim 1 wherein the size of the auxiliary holes is minimized while meeting the requirements for opening.

4. A process for manufacturing a cylinder for a pressure vessel according to claim 1, wherein a flaw detection step is provided between the sixth step and the seventh step.

5. The process for making a pressure vessel cylinder according to claim 1, further comprising a grinding step after the cutting of the ribs.