Manufacturing method of large 2205 / 2507 duplex stainless steel static mixer

Abstract

The invention provides a manufacturing method of a large 2205 / 2507 duplex stainless steel static mixer, which can effectively solve the problems of improving the product quality and prolonging the service life, the static mixer comprises an upper flange plate, a pipe body, an SK type spiral blade and a lower flange plate, and the manufacturing method comprises the following steps of: determining the length of the pipe body, processing the upper flange plate and the lower flange plate, forming grooves in the corresponding surfaces of the two flange plates, and manufacturing the pipe body. The two ends of the pipe body are provided with the bosses, the bosses are arranged in the grooves, the upper flange plate and the lower flange plate are welded to the two ends of the pipe body respectively after the bosses are embedded into the two ends of the pipe body to be positioned, a pressing mould is manufactured, the SK type spiral blade is pressed, and the pressed SK type spiral blade is welded into the pipe body 2 according to requirements. The method is scientific and reasonable in design, easy to operate, good in product quality, long in service life, high in production efficiency, capable of reducing cost and increasing efficiency, suitable for industrial batch production, innovative in static mixer equipment manufacturing method and huge in economic and social benefits.

Description

Technical Field

[0001] The invention relates to mechanical manufacturing, in particular to a manufacturing method of a large 2205 / 2507 duplex stainless steel static mixer for an alumina high-efficiency thickener. Background Art

[0002] Static mixer is a key supporting equipment of the feeding system of alumina high-efficiency thickener. It uses multiple mixing spiral unit blades fixed in the pipe and arranged at a certain angle to change the flow state of the material in the pipe, so as to achieve the purpose of good dispersion and full mixing of the feed slurry. The reason why it is called a "static" mixer is that there are no moving parts in the pipeline, only static elements. The spiral unit blades will be impacted by the slurry in the static mixer and are vulnerable parts. Their quality and service life directly affect the use effect and service life of the static mixer. In particular, with the continuous improvement of the production capacity of the domestic alumina industry in recent years, the specifications of the sedimentation tanks have been continuously increased, and the feed pipe diameter of the static mixer has increased from D From N300 to DN700, the pipe body is mostly made of fiberglass or other corrosion-resistant materials. The traditional large-scale static mixer spiral unit blades are made by manual sheet metal hammering during manufacturing. The torsion angle of the spiral unit blades does not meet the design requirements, and the external dimension error is large. At the same time, there are mechanical knocking pits on the surface, which cannot guarantee the product quality and lead to a short service life. If the above problems cannot be effectively solved during manufacturing, the use effect and service life of the static mixer will be seriously affected, which will directly affect the production efficiency and economic benefits of the alumina high-efficiency thickener. Therefore, how to develop a manufacturing method for a static mixer and improve product quality and service life is a technical problem that needs to be solved urgently. Summary of the invention

[0003] In view of the above situation, in order to overcome the shortcomings of the prior art, the purpose of the present invention is to provide a method for manufacturing a large 2205 / 2507 duplex stainless steel static mixer, which can effectively solve the problem of improving product quality and service life.

[0004] The technical solution provided by the present invention is a method for manufacturing a large 2205 / 2507 duplex stainless steel static mixer, the static mixer comprising an upper flange plate 1, a tube body 2, an SK type spiral blade 3 and a lower flange plate 4, the tube body 2 being a hollow tube body made of 2205 / 2507 duplex stainless steel with an inner diameter of DN700 and a wall thickness of 10 mm, and the manufacturing method comprising the following steps: (1) First, determine the length of the pipe body 2 according to the needs, process the upper flange plate and the lower flange plate, and grind the steel plate used to make the flange during the forming and installation surfaces to make the roughness meet the specified requirements, and the surface is smooth and free of barbs; (2) A circumferential safety positioning groove is formed on the corresponding side of the upper flange plate 1 and the lower flange plate 4, and corresponding bosses are provided at both ends of the tube body 2; (3) Place the bosses at both ends of the tube body 2 in the safety positioning grooves, and after being nested in the two ends of the tube body for positioning, vertically weld the upper flange plate 1 and the lower flange plate 4 to the two ends of the tube body 2 respectively; after welding, perform heat treatment to eliminate welding stress; (4) Making a pressing mold: The tire is composed of an upper positioning plate 5, a lower positioning plate 8, an upper tire 6 and a lower tire 7 which are vertically arranged. The upper tire 6 and the lower tire 7 are welded to the upper positioning plate 5 and the lower positioning plate 8 respectively, and the welded positioning plates are matched rectangular shapes. The upper tire 6 is welded to the upper positioning plate 5, and the lower tire 7 is welded to the lower positioning plate 8. Both the upper tire 6 and the lower tire 7 are solid structures formed by welding a plurality of steel plates with different heights on the left and right sides. The height of the steel plate on the left side of the upper tire 6 decreases successively, and the height of the steel plate on the right side increases successively. The height of the steel plate on the left side of the lower tire 7 increases successively, and the height of the steel plate on the right side decreases successively. The lower surface of the upper tire 6 matches the upper surface of the lower tire 7, so that the pressing surface forms a gradient arc structure with the same radius of curvature, thereby ensuring that the torsion angle of the spiral unit sheet 3 meets the requirements. The welding can be electric welding, explosion welding or hot pressure welding, and different welding methods can be used according to the specific requirements of the steel plate (known technology, no further details are given); (5) Pressed SK type spiral blades The upper tire 6 is welded to the upper positioning plate 5 and the upper positioning plate 5 is fixed to the force arm of the press through a rigid connection. The lower tire 7 is welded to the lower positioning plate 8 and fixed to the press platform to ensure the positioning of the upper and lower tires. Then, the 2205 / 2507 duplex stainless steel plate (hereinafter referred to as the steel plate) used to make SK type spiral blades is placed in the gap between the upper tire 6 and the lower tire 7. When pressing the spiral blades, the steel plate for making the spiral blades is placed on the lower tire 7, the upper tire 6 is pressed on the steel plate, the press is started, and pressing is performed to ensure that the longitudinal offset of the pressing center is ≤2mm, and the 2205 / 2507 duplex stainless steel plate is pressed into an SK type spiral blade; (6) Assembly The pressed SK type spiral blades are welded in the pipe body 2 by alternately and evenly positioning and welding a plurality of SK type spiral blades from the middle of the pipe body 2 to both ends along the central axis of the pipe body 2, and making the twist angle of the single blade cross 90° in both directions, and the left and right spiral angles are equal, so as to obtain a large 2205 / 2507 duplex stainless steel static mixer finished product.

[0005] The method of the present invention is novel and unique, scientific and reasonable, easy to produce and easy to operate. Through the correct installation of the upper and lower flange plates and the trough body feeding system, the material can be mixed more evenly when passing through the SK-type spiral blades pressed by the mold, and the optimization of the tube axis size also significantly increases the feed amount, shortens the production preparation time, and improves production efficiency. The structural design is reasonable and easy to use, which greatly reduces the work intensity of workers and improves production efficiency at the same time. The effect is good and it is suitable for mass production. It is an innovation in the manufacturing method of static mixer equipment with huge economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 It is a sectional front view of the static mixer of the present invention.

[0007] Figure 2 It is a multi-directional (a, b) three-dimensional structural diagram of the SK type spiral blade of the present invention.

[0008] Figure 3 This is a three-dimensional diagram of the pressing jig of the present invention pressed on a blade-making steel plate (the dotted line portion is the blade). DETAILED DESCRIPTION

[0009] The specific implementation modes of the present invention are described in detail below in combination with embodiments and specific situations.

[0010] The present invention discloses a method for manufacturing a large-scale 2205 / 2507 duplex stainless steel static mixer. The static mixer comprises an upper flange plate 1, a tube body 2, an SK-type spiral blade 3 and a lower flange plate 4. The tube body 2 is a hollow tube body made of 2205 / 2507 duplex stainless steel with an inner diameter of DN700 and a wall thickness of 10 mm. The manufacturing method comprises the following steps: (1) First, determine the length of the pipe body 2 according to the needs, process the upper flange plate and the lower flange plate, and grind the steel plate used to make the flange during the forming and installation surfaces to make the roughness meet the specified requirements, and the surface is smooth and free of barbs; (2) A circumferential safety positioning groove is formed on the corresponding side of the upper flange plate 1 and the lower flange plate 4, and corresponding bosses are provided at both ends of the tube body 2; (3) Place the bosses at both ends of the tube body 2 in the safety positioning grooves, and after being nested in the two ends of the tube body for positioning, vertically weld the upper flange plate 1 and the lower flange plate 4 to the two ends of the tube body 2 respectively; after welding, perform heat treatment to eliminate welding stress; (4) Making a pressing mold: The tire is composed of an upper positioning plate 5, a lower positioning plate 8, an upper tire 6 and a lower tire 7 which are vertically arranged. The upper tire 6 and the lower tire 7 are welded to the upper positioning plate 5 and the lower positioning plate 8 respectively, and the welded positioning plates are matched rectangular shapes. The upper tire 6 is welded to the upper positioning plate 5, and the lower tire 7 is welded to the lower positioning plate 8. Both the upper tire 6 and the lower tire 7 are solid structures formed by welding a plurality of steel plates with different heights on the left and right sides. The height of the steel plate on the left side of the upper tire 6 decreases successively, and the height of the steel plate on the right side increases successively. The height of the steel plate on the left side of the lower tire 7 increases successively, and the height of the steel plate on the right side decreases successively. The lower surface of the upper tire 6 matches the upper surface of the lower tire 7, so that the pressing surface forms a gradient arc structure with the same radius of curvature, thereby ensuring that the torsion angle of the spiral unit sheet 3 meets the requirements. The upper tire 6 and the lower tire 7 each have two sets of counterclockwise and two sets of clockwise to meet the needs of manufacturing SK type spiral blades; The cross section of each layer of steel plate of the upper tire 6 and the lower tire 7 is an oblique cross section, and the upper and lower parts are complementary, the left-hand tire is horizontally inward, and the left and right heights of each layer of steel plate change in an equal gradient; (5) Pressed SK type spiral blades The upper tire 6 is welded to the upper positioning plate 5 and the upper positioning plate 5 is fixed to the force arm of the press through a rigid connection. The lower tire 7 is welded to the lower positioning plate 8 and fixed to the press platform to ensure the positioning of the upper and lower tires. Then, the 2205 / 2507 duplex stainless steel plate (hereinafter referred to as the steel plate) used to make SK type spiral blades is placed in the gap between the upper tire 6 and the lower tire 7. When pressing the spiral blades, the steel plate for making the spiral blades is placed on the lower tire 7, the upper tire 6 is pressed on the steel plate, the press is started, and pressing is performed to ensure that the longitudinal offset of the pressing center is ≤2mm, and the 2205 / 2507 duplex stainless steel plate is pressed into an SK type spiral blade; When pressing the spiral blade, the steel plate for making the spiral blade is placed on the lower tire 7, and the upper tire 6 is pressed on the steel plate. The height between the upper positioning plate 5 and the lower positioning plate 8 is H, the height of the left side of the lower tire steel plate is A, and the height of the right side is B, the height of the left side of the upper tire steel plate is C, and the height of the right side is D, and the thickness of the steel plate is N. Then the sum of A, C, and N is equal to the height H between the upper and lower positioning plates, and the sum of B, D, and N is equal to the height H between the upper and lower positioning plates; when the horizontal thickness of the right-hand rotation increases, A gradually increases, B gradually decreases, and correspondingly C decreases and B increases, and the opposite is true for the left-hand rotation (see Figure 3 As shown), to ensure the matching of the blades; (6) Assembly The pressed SK type spiral blades are welded in the pipe body 2 by alternately and evenly positioning and welding a plurality of SK type spiral blades from the middle of the pipe body 2 to both ends along the central axis of the pipe body 2, and making the twist angle of the single blade cross 90° in both directions, and the left and right spiral angles are equal, so as to obtain a large 2205 / 2507 duplex stainless steel static mixer finished product.

[0011] The large-scale 2205 / 2507 duplex stainless steel static mixer of the present invention has a simple structure and is easy to produce and prepare. The standardized production saves manpower and material resources, improves work efficiency, ensures product quality, and increases the service life of the product by more than two times. It can be used for the production of spiral blades (units) of different specifications, realizes batch and rapid industrial production, can greatly save costs, and effectively improve production efficiency. Field tests and tests have shown that the cost can be saved by more than 40%, and the production efficiency can be increased by 2-3 times. It is an innovation in the large-scale stainless steel static mixer in the thickener series, and has huge economic and social benefits.

Claims

1. A method for manufacturing a large 2205 / 2507 duplex stainless steel static mixer, the static mixer comprising an upper flange plate 1, a tube body 2, an SK-type spiral blade 3 and a lower flange plate 4, wherein the tube body 2 is a hollow tube body made of 2205 / 2507 duplex stainless steel with an inner diameter of DN700 and a wall thickness of 10 mm, and the manufacturing method comprises the following steps: (1) First, determine the length of the pipe body 2 according to the needs, process the upper flange plate and the lower flange plate, and grind the steel plate used to make the flange during the forming and installation surfaces to make the roughness meet the specified requirements, and the surface is smooth and free of barbs; (2) A circumferential safety positioning groove is formed on the corresponding side of the upper flange plate 1 and the lower flange plate 4, and corresponding bosses are provided at both ends of the tube body 2; (3) Place the bosses at both ends of the tube body 2 in the safety positioning grooves, and after being nested in the two ends of the tube body for positioning, vertically weld the upper flange plate 1 and the lower flange plate 4 to the two ends of the tube body 2 respectively; after welding, perform heat treatment to eliminate welding stress; (4) Making a pressing mold: The tire is composed of an upper positioning plate 5, a lower positioning plate 8, an upper tire 6 and a lower tire 7 which are vertically arranged. The upper tire 6 and the lower tire 7 are welded to the upper positioning plate 5 and the lower positioning plate 8 respectively, and the welded positioning plates are matched rectangular shapes. The upper tire 6 is welded to the upper positioning plate 5, and the lower tire 7 is welded to the lower positioning plate 8. Both the upper tire 6 and the lower tire 7 are solid structures formed by welding a plurality of steel plates with different heights on the left and right sides. The height of the steel plate on the left side of the upper tire 6 decreases successively, and the height of the steel plate on the right side increases successively. The height of the steel plate on the left side of the lower tire 7 increases successively, and the height of the steel plate on the right side decreases successively. The lower surface of the upper tire 6 matches the upper surface of the lower tire 7, so that the pressing surface forms a gradient arc structure with the same radius of curvature, thereby ensuring that the torsion angle of the spiral unit sheet 3 meets the requirements. (5) Pressed SK type spiral blades The upper tire 6 is welded to the upper positioning plate 5 and the upper positioning plate 5 is fixed to the force arm of the press through a rigid connection. The lower tire 7 is welded to the lower positioning plate 8 and fixed to the press platform to ensure the positioning of the upper and lower tires. Then, the 2205 / 2507 duplex stainless steel plate (hereinafter referred to as the steel plate) used to make SK type spiral blades is placed in the gap between the upper tire 6 and the lower tire 7. When pressing the spiral blades, the steel plate for making the spiral blades is placed on the lower tire 7, the upper tire 6 is pressed on the steel plate, the press is started, and pressing is performed to ensure that the longitudinal offset of the pressing center is ≤2mm, and the 2205 / 2507 duplex stainless steel plate is pressed into an SK type spiral blade; (6) Assembly The pressed SK type spiral blades are welded in the pipe body 2 by alternately and evenly positioning and welding a plurality of SK type spiral blades from the middle of the pipe body 2 to both ends along the central axis of the pipe body 2, and making the twist angle of the single blade cross 90° in both directions, and the left and right spiral angles are equal, so as to obtain a large 2205 / 2507 duplex stainless steel static mixer finished product.

2. The method for manufacturing a large-scale 2205 / 2507 duplex stainless steel static mixer according to claim 1, characterized in that: The upper tire 6 and the lower tire 7 are provided with two sets of counterclockwise and two sets of clockwise to meet the needs of manufacturing SK type spiral blades.

3. The method for manufacturing a large 2205 / 2507 duplex stainless steel static mixer according to claim 1, characterized in that: The cross section of each layer of steel plate of the upper tire 6 and the lower tire 7 is an oblique cross section, and the upper and lower parts are complementary, the left-hand tire is horizontally inward, and the left and right heights of each layer of steel plate vary in equal gradients.

4. The method for manufacturing a large-scale 2205 / 2507 duplex stainless steel static mixer according to claim 1, characterized in that: When pressing the spiral blade, the steel plate for making the spiral blade is placed on the lower tire 7, and the upper tire 6 is pressed on the steel plate. The height between the upper positioning plate 5 and the lower positioning plate 8 is H, the height of the left side of the lower tire steel plate is A, and the height of the right side is B, the height of the left side of the upper tire steel plate is C, and the height of the right side is D, and the thickness of the steel plate is N. Then the sum of A, C, and N is equal to the height H between the upper and lower positioning plates, and the sum of B, D, and N is equal to the height H between the upper and lower positioning plates; when the horizontal thickness of the right-handed rotation increases, A gradually increases, and B gradually decreases, and accordingly C decreases and B increases. The opposite is true for the left-handed rotation to ensure the matching of the blades.

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