Machining process for precision forming of large thin-wall storage tank hemispheroid

Abstract

The invention discloses a machining process for precision forming of a large thin-wall storage tank hemispheroid. The machining process comprises the steps of plasma gas cutting, punch forming, cutting, shaping, finish turning of an inner spherical surface, finish turning of an outer spherical surface and surface treatment. The diameter of the hemispheroid of a large thin-wall storage tank is phi925, the wall thickness of the hemispheroid is delta 3.9<0><+0.3>, the ovality of the hemispheroid is phi 0.3; and the diaphragm type storage tank is high in size requirement and high in numerical control machining difficulty, and particularly, the diaphragm type storage tank is made of aluminum alloy and is insufficient in strength and rigidity, large in machining deformation and high in machining difficulty, so that the diaphragm type storage tank is a hemispheroid with larger diameter, the surface linear speed changes along with changes of the height of a part, different main shaft rotatingspeeds need to be selected according to different annular belts during turning, and therefore the machining difficulty is further improved. According to the machining process, ultrasonic measurementand special tool expansion clamping are explored and adopted for numerical control machining, the wall thickness tolerance of an upper hemisphere and a lower hemisphere of the storage tank is 3.9<0><+0.3>, the ovality is phi 0.3, the tensile strength sigma b after heat treatment is larger than or equal to 340 MPa, and the elongation is larger than 10%.

Description

technical field

[0001] The invention belongs to the technical field of storage tank manufacturing, and in particular relates to a processing technology for precise forming of a hemisphere of a large thin-walled storage tank. Background technique

[0002] As the main pressure vessel of the aerospace power system, the tank is used to store liquid media (such as propellants, etc.), carry a certain pressure, and realize functions such as pressure supply. The performance of the tank directly affects the service life and reliability of the spacecraft. sex. According to different structures and working principles, storage tanks are mainly divided into surface tension storage tanks, diaphragm storage tanks, capsule storage tanks, membrane box storage tanks, etc. Regardless of the storage tank, the shell is the main load-bearing part , its structure and performance directly affect the performance of the tank. At present, the diameter of most of the large thin-walled rotary parts pr...

Examples

Embodiment 1

[0048] Such as figure 1 , figure 2 , image 3 As shown, a processing technology for precision forming of a large thin-walled storage tank hemisphere, including plasma gas cutting, stamping forming, cutting, shaping, finishing the inner spherical surface, finishing the outer spherical surface, and surface treatment steps, specifically includes the following steps:

[0049] (1) Plasma gas cutting: first calculate the size of the blank, then use plasma gas cutting equipment to cut the outer circle, and then punch the blank and cut it;

[0050] (2) Stamping forming: Grinding and cleaning with a pneumatic grinding wheel. Steps (1) The cutting slag on the edge of the billet cut by plasma gas, and then using a 2000T hydraulic drawing forming die and an aluminum alloy special annealing furnace to repeat drawing forming and annealing four times. Then carry out the fifth drawing forming to obtain the hemispherical semi-finished product;

[0051] Using 2000T hydraulic drawing forming...

Embodiment 2

[0060] Such as figure 1 , figure 2 , image 3 As shown, a processing technology for precision forming of a large thin-walled storage tank hemisphere, including plasma gas cutting, stamping forming, cutting, shaping, finishing the inner spherical surface, finishing the outer spherical surface, and surface treatment steps, specifically includes the following steps:

[0061] (1) Plasma gas cutting: first calculate the size of the blank, then use plasma gas cutting equipment to cut the outer circle, and then punch the blank and cut it;

[0062] (2) Stamping forming: Grinding and cleaning with a pneumatic grinding wheel. Steps (1) The cutting slag on the edge of the billet cut by plasma gas, and then using a 2000T hydraulic drawing forming die and an aluminum alloy special annealing furnace to repeat drawing forming and annealing four times. Then carry out the fifth drawing forming to obtain the hemispherical semi-finished product;

[0063] Using 2000T hydraulic drawing forming...

Embodiment 3

[0072] Such as figure 1 , figure 2 , image 3 As shown, a processing technology for precision forming of a large thin-walled storage tank hemisphere, including plasma gas cutting, stamping forming, cutting, shaping, finishing the inner spherical surface, finishing the outer spherical surface, and surface treatment steps, specifically includes the following steps:

[0073] (1) Plasma gas cutting: first calculate the size of the blank, then use plasma gas cutting equipment to cut the outer circle, and then punch the blank and cut it;

[0074] (2) Stamping forming: Grinding and cleaning with a pneumatic grinding wheel. Steps (1) The cutting slag on the edge of the billet cut by plasma gas, and then using a 2000T hydraulic drawing forming die and an aluminum alloy special annealing furnace to repeat drawing forming and annealing four times. Then carry out the fifth drawing forming to obtain the hemispherical semi-finished product;

[0075] Using 2000T hydraulic drawing forming...

technical field

[0001] The invention belongs to the technical field of storage tank manufacturing, and in particular relates to a processing technology for precise forming of a hemisphere of a large thin-walled storage tank. Background technique

[0002] As the main pressure vessel of the aerospace power system, the tank is used to store liquid media (such as propellants, etc.), carry a certain pressure, and realize functions such as pressure supply. The performance of the tank directly affects the service life and reliability of the spacecraft. sex. According to different structures and working principles, storage tanks are mainly divided into surface tension storage tanks, diaphragm storage tanks, capsule storage tanks, membrane box storage tanks, etc. Regardless of the storage tank, the shell is the main load-bearing part , its structure and performance directly affect the performance of the tank. At present, the diameter of most of the large thin-walled rotary parts pr...

Examples

Embodiment 1

[0048] Such as figure 1 , figure 2 , image 3 As shown, a processing technology for precision forming of a large thin-walled storage tank hemisphere, including plasma gas cutting, stamping forming, cutting, shaping, finishing the inner spherical surface, finishing the outer spherical surface, and surface treatment steps, specifically includes the following steps:

[0049] (1) Plasma gas cutting: first calculate the size of the blank, then use plasma gas cutting equipment to cut the outer circle, and then punch the blank and cut it;

[0050] (2) Stamping forming: Grinding and cleaning with a pneumatic grinding wheel. Steps (1) The cutting slag on the edge of the billet cut by plasma gas, and then using a 2000T hydraulic drawing forming die and an aluminum alloy special annealing furnace to repeat drawing forming and annealing four times. Then carry out the fifth drawing forming to obtain the hemispherical semi-finished product;

[0051] Using 2000T hydraulic drawing forming...

Embodiment 2

[0060] Such as figure 1 , figure 2 , image 3 As shown, a processing technology for precision forming of a large thin-walled storage tank hemisphere, including plasma gas cutting, stamping forming, cutting, shaping, finishing the inner spherical surface, finishing the outer spherical surface, and surface treatment steps, specifically includes the following steps:

[0061] (1) Plasma gas cutting: first calculate the size of the blank, then use plasma gas cutting equipment to cut the outer circle, and then punch the blank and cut it;

[0062] (2) Stamping forming: Grinding and cleaning with a pneumatic grinding wheel. Steps (1) The cutting slag on the edge of the billet cut by plasma gas, and then using a 2000T hydraulic drawing forming die and an aluminum alloy special annealing furnace to repeat drawing forming and annealing four times. Then carry out the fifth drawing forming to obtain the hemispherical semi-finished product;

[0063] Using 2000T hydraulic drawing forming...

Embodiment 3

[0072] Such as figure 1 , figure 2 , image 3 As shown, a processing technology for precision forming of a large thin-walled storage tank hemisphere, including plasma gas cutting, stamping forming, cutting, shaping, finishing the inner spherical surface, finishing the outer spherical surface, and surface treatment steps, specifically includes the following steps:

[0073] (1) Plasma gas cutting: first calculate the size of the blank, then use plasma gas cutting equipment to cut the outer circle, and then punch the blank and cut it;

[0074] (2) Stamping forming: Grinding and cleaning with a pneumatic grinding wheel. Steps (1) The cutting slag on the edge of the billet cut by plasma gas, and then using a 2000T hydraulic drawing forming die and an aluminum alloy special annealing furnace to repeat drawing forming and annealing four times. Then carry out the fifth drawing forming to obtain the hemispherical semi-finished product;

[0075] Using 2000T hydraulic drawing forming...

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