CN109048225B - Manhole processing technology of liquid storage tank - Google Patents
Manhole processing technology of liquid storage tank Download PDFInfo
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- CN109048225B CN109048225B CN201811036821.5A CN201811036821A CN109048225B CN 109048225 B CN109048225 B CN 109048225B CN 201811036821 A CN201811036821 A CN 201811036821A CN 109048225 B CN109048225 B CN 109048225B
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Abstract
The invention provides a manhole processing technology of a liquid storage tank, which comprises the following processing steps: taking an aluminum raw material, preheating and preserving heat for a period of time, then continuously heating to 500-550 ℃, and then pushing into a plate die for extrusion molding; conveying the formed aluminum material discharged from a discharge hole at one side of the plate die to a heat dissipation area through a transmission device, and cooling to room temperature to obtain an initial product; bending and rolling the primary product into a round aluminum material with a specified specification by a rolling machine; the invention has the advantages that the gaps of the two ends and the tail ends of the round aluminum material are welded, then the numerical control punching is carried out according to different specification requirements, and the subsequent finish machining is carried out, so that the invention is obtained by reasonable raw material selection, process and parameter improvement, welding beads are reduced by 90%, the airtight effect is good, the process period is effectively shortened, the time and the labor are saved, the manhole is integrally formed, the stability is strong, the comprehensive mechanical property is good, the cost is low, the operation is simple and convenient, and the industrial application is convenient.
Description
Technical Field
The invention relates to the technical field of manhole production and processing, in particular to a manhole processing technology of a liquid storage tank.
Background
The manhole is an opening on the side surface of the oil tank and the liquid storage tank, and is used for allowing a person to enter the tank for overhauling, cleaning and other operations, and is divided into an emergency pressure relief manhole, an explosion-proof fire-retardant breathing manhole, a tank top manhole, a tank wall manhole, a manhole with a core and the like. Manholes are typically made from 304, 316L stainless steel plate or carbon steel.
The manhole is a safety emergency ventilating device arranged on the top of the storage tank, and is usually matched with a fire preventer and a mechanical breather valve for use, so that the accident caused by the damage of the storage tank due to the sharp overpressure or vacuum in the tank caused by accident can be avoided, the manhole also has the function of safe fire resistance, and is a safety device for protecting the storage tank, and the manhole is particularly suitable for vault normal-pressure tanks which are capped by nitrogen for storing materials. The device has the advantages of constant pressure discharge, constant pressure suction, flexible opening and closing, safe fire resistance, compact structure, good sealing performance, safety, reliability and the like.
The manhole of the non-metal liquid storage tank is arranged on the top of the tank, and the manhole of the metal liquid storage tank is arranged on the lowest ring plate of the tank wall. The most of the round holes are round holes with the diameter of 600mm, the center of the round holes is 750mm away from the bottom plate, and the round holes are also called as passage doors for cleaning the liquid storage tank or for entering and exiting the liquid storage tank by maintenance personnel. And the manhole is used for lighting and ventilating during maintenance and cleaning of the liquid storage tank. The volume of the vertical liquid storage tank is 5000m3Set 1 ~ 2 manholes, 5000m3And 2 manholes are arranged above the manhole. The manhole should be installed no more than 90 ° from the oil and water line. When only one manhole is arranged, the manhole is opposite to the light hole on the top of the tank; when 2 manholes are provided, one of which is located opposite the light-transmitting hole and the other of which should be at least 90 ° apart from the first one. As the manhole is arranged on the lowermost layer body ring of the liquid storage tank, the leakage prevention is very important, the flatness of the joint surface of the two flanges is required to be ensured, the phenomenon of floating and twisting is avoided, and the reinforcing plate and the flanges are cut on the whole steel plate as much as possible without splicingAnd sealing rings are processed on the flange and the cover plate, special attention needs to be paid to protection in construction, a 3mm thick asbestos rubber gasket is used for sealing, fracture is not allowed, and when bolts are tightened on the manhole cover plate, force needs to be uniformly applied to a diagonal to prevent the deformation of the manhole cover.
At present, two steel flanges are butted, welded, formed and punched in most of the market, but the process is complex, the period is long, and the cost is high. At present, the manhole processing is also performed by adopting the aluminum material, but the more welding of the aluminum material, the more defects are caused, the more the welding of the aluminum material is, the more the gas tightness of the manhole is affected integrally, the damage to the welding bead of the base metal during the repair is caused, the attractiveness is affected, the stress deformation during the welding cannot be avoided, the technical requirement on a welder is very high, and otherwise, the effect of using the gas tightness cannot be achieved. Therefore, the improvement of the manhole processing technology of the liquid storage tank is urgently needed.
Disclosure of Invention
Aiming at the existing problems, the invention provides the manhole processing technology of the liquid storage tank, through reasonable process and parameter improvement, the welding bead is reduced by 90%, the airtight effect is good, the process period is effectively shortened, the time and the labor are saved, the manhole is integrally formed, the stability is strong, the comprehensive mechanical property is good, the cost is low, the operation is simple and convenient, and the manhole processing technology is convenient for industrial application. The manhole manufactured by the process can be used for but not limited to a liquid storage tank, and can also be used for manholes on oil tanks, oil tank trucks and the like.
In order to achieve the above object, the present invention adopts the following technical solutions:
a manhole processing technology of a liquid storage tank comprises the following processing steps:
1) taking an aluminum raw material, preheating and preserving heat for a period of time, then continuously heating to 500-550 ℃, pushing into a plate mold for extrusion molding, heating to 500-550 ℃, preserving heat for a period of time (softening occurs), and then carrying out extrusion molding;
2) conveying the formed aluminum material discharged from a discharge hole at one side of the plate die to a heat dissipation area through a transmission device, and cooling to room temperature to obtain an initial product;
3) bending and rolling the primary product into a round aluminum material with a specified specification by a rolling machine;
4) welding two end-to-end gaps of the round aluminum material, then cutting the section by a cutting machine, carrying out numerical control punching according to different specification requirements, and carrying out subsequent finish machining to obtain the product.
Preferably, the aluminum raw material is an aluminum bar or an aluminum ingot, wherein the aluminum content is more than 65 wt%, and the aluminum purity is more than 95%.
Preferably, the aluminum raw material also comprises boron, tungsten and magnesium, and the content of boron is less than 1.5 wt%, the content of tungsten is less than 0.6 wt% and the content of magnesium is less than 2.5 wt%.
Preferably, the preheating temperature in the step 1) is 450-.
Preferably, the extrusion molding power of the plate mold in the step 1) is 48-50kW, the pressure is 290-300T, and the advancing speed is 0.45-0.55 m/min.
Preferably, the cross section of the formed aluminum material in the step 2) is in a "]" shape.
Preferably, the heat dissipation area in the step 2) is air-cooled, and the cooling time is at least 1 h.
Preferably, the first product is rolled by the vertical setting's of step 3) medium-pressure rolling machine two rollers, and the below roller is the drive roll that links to each other with the motor, and the top is the driven voller, and motor 500: the 1 drives a speed reducer to be connected with the roll shaft in a transmission way.
Preferably, the two rollers of the rolling machine roll the primary product under the pressure of 1-1.5MPa for 4-5 times.
Due to the adoption of the technical scheme, the invention has the beneficial effects that: through reasonable raw material selection and process and parameter improvement, the manufactured manhole welding bead is reduced by 90%, the airtight effect is good, the process period is effectively shortened, time and labor are saved, the manhole is integrally formed, the stability is strong, the comprehensive mechanical property is good, the cost is low, the operation is simple and convenient, and the industrial application is facilitated.
The softening ductility of alloy inner structure has effectively been improved through preheating before the heating extrusion, balanced transmissibility is good, be favorable to later stage extruded smooth transition, in addition, extrusion parameter's reasonable injecion, the compaction homogeneity of section bar has effectively been improved, whole density grow, the rigidity reinforcing, afterwards, it passes through the book machine with it, with suitable extrusion number of times and extrusion pressure bending, it is unstable to have guaranteed that the inner structure that structure extension deformation caused, the inhomogeneous phenomenon of local atress, comprehensive steadiness is good, mechanical properties obviously improves.
In conclusion, the invention has the following advantages:
1. the welding bead is reduced by 90%, the airtight effect is good, and the defects of long welding time, high technical requirement on welding workers, short welding time and low labor cost of the prior art are overcome.
2. The profile is high in density and high in rigidity due to the special extrusion process, the bending process is examined for the profile, if the profile is defective, the bending process cannot be realized, the material and quality of a product are reflected to a great extent, the quality of a formed manhole is guaranteed, and the performance is stable.
3. Because the structure itself is integrated into one piece, does not have the key position and opens the welding, even receive strong impact and also can not ftracture, effectively protect cylinder body internal liquid not to reveal.
4. The cost is low, the operation is simple and easy to realize, and the requirement on the professional performance of personnel is not high.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a sectional view of a starting product of the present invention;
FIG. 2 is a schematic view of a round aluminum product of the present invention;
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without any inventive step, are within the scope of the present invention.
Example 1:
a manhole processing technology of a liquid storage tank comprises the following processing steps:
1) taking an aluminum raw material, preheating and preserving heat for a period of time, then continuously heating to 530 ℃, and pushing the aluminum raw material into a plate die for extrusion forming;
2) conveying the formed aluminum material discharged from a discharge hole at one side of the plate die to a heat dissipation area through a transmission device, cooling to room temperature (adopting air cooling, wherein the cooling time is at least 1h) to obtain an initial product (see figure 1, the cross section of the formed aluminum material is in a shape of' ]);
3) bending and rolling the primary product into a round aluminum material with a specified specification by a rolling machine (see figure 2); the rolling machine adopts the two rollers of perpendicular setting to roll the primary product, and the below roller is the drive roll that links to each other with the motor, and the top is the driven voller, and motor 500: 1, driving a speed reducer to be in transmission connection with a roll shaft, and rolling the primary product by a double roll of a rolling machine at a rolling pressure of 1.1MPa for 4 times;
4) welding two end-to-end gaps of the round aluminum material, then cutting the section by a cutting machine, carrying out numerical control punching according to different specification requirements, and carrying out subsequent finish machining to obtain the product.
Specifically, the aluminum raw material is aluminum bar or aluminum ingot, wherein the aluminum content is 68 wt%, the aluminum purity is higher than 95%, the aluminum raw material also comprises boron, tungsten and magnesium, the boron content is 1.5 wt%, the tungsten content is 0.5 wt%, and the magnesium content is 2 wt%.
In the step 1), the preheating temperature is 480 ℃, and the heat preservation time is 10 min; in the step 1), the extrusion forming power of the plate mould is 48kW, the pressure is 300T, and the propelling speed is 0.5 m/min.
Example 2:
a manhole processing technology of a liquid storage tank comprises the following processing steps:
1) taking an aluminum raw material, preheating and preserving heat for a period of time, then continuously heating to 550 ℃, and pushing into a plate die for extrusion molding;
2) conveying the formed aluminum material discharged from a discharge hole at one side of the plate die to a heat dissipation area through a transmission device, cooling to room temperature (adopting air cooling, wherein the cooling time is at least 1h) to obtain an initial product (see figure 1, the cross section of the formed aluminum material is in a shape of' ]);
3) bending and rolling the primary product into a round aluminum material with a specified specification by a rolling machine (see figure 2); the rolling machine adopts the two rollers of perpendicular setting to roll the primary product, and the below roller is the drive roll that links to each other with the motor, and the top is the driven voller, and motor 500: 1, driving a speed reducer to be in transmission connection with a roll shaft, and rolling the primary product by a double roll of a rolling machine for 5 times under the rolling pressure of 1.5 MPa;
4) welding two end-to-end gaps of the round aluminum material, then cutting the section by a cutting machine, carrying out numerical control punching according to different specification requirements, and carrying out subsequent finish machining to obtain the product.
Specifically, the aluminum raw material is an aluminum bar or an aluminum ingot, wherein the aluminum content is 70 wt%, the aluminum purity is higher than 95%, the aluminum raw material also comprises boron, tungsten and magnesium, the boron content is 0.5 wt%, the tungsten content is 0.5 wt%, and the magnesium content is 2.5 wt%.
In the step 1), the preheating temperature is 450 ℃, and the heat preservation time is 10 min; the extrusion forming power of the panel mould in the step 1) is 50kW, the pressure is 290T, and the propelling speed is 0.45 m/min.
Example 3:
a manhole processing technology of a liquid storage tank comprises the following processing steps:
1) taking an aluminum raw material, preheating and preserving heat for a period of time, then continuously heating to 550 ℃, and pushing into a plate die for extrusion molding;
2) conveying the formed aluminum material discharged from a discharge hole at one side of the plate die to a heat dissipation area through a transmission device, cooling to room temperature (adopting air cooling, wherein the cooling time is at least 1h) to obtain an initial product (see figure 1, the cross section of the formed aluminum material is in a shape of' ]);
3) bending and rolling the primary product into a round aluminum material with a specified specification by a rolling machine (see figure 2); the rolling machine adopts the two rollers of perpendicular setting to roll the primary product, and the below roller is the drive roll that links to each other with the motor, and the top is the driven voller, and motor 500: 1, driving a speed reducer to be in transmission connection with a roll shaft, and rolling the primary product by a double roll of a rolling machine for 5 times under the rolling pressure of 1.5 MPa;
4) welding two end-to-end gaps of the round aluminum material, then cutting the section by a cutting machine, carrying out numerical control punching according to different specification requirements, and carrying out subsequent finish machining to obtain the product.
Specifically, the aluminum raw material is an aluminum bar or an aluminum ingot, wherein the aluminum content is 65 wt%, the aluminum purity is higher than 95%, the aluminum raw material also comprises boron, tungsten and magnesium, the boron content is 1.2 wt%, the tungsten content is 0.6 wt%, and the magnesium content is 1.5 wt%.
In the step 1), the preheating temperature is 450 ℃, and the heat preservation time is 5 min; in the step 1), the extrusion forming power of the plate mould is 48kW, the pressure is 300T, and the propelling speed is 0.55 m/min.
Example 4:
a manhole processing technology of a liquid storage tank comprises the following processing steps:
1) taking an aluminum raw material, preheating and preserving heat for a period of time, then continuously heating to 500 ℃, and pushing the aluminum raw material into a plate die for extrusion forming;
2) conveying the formed aluminum material discharged from a discharge hole at one side of the plate die to a heat dissipation area through a transmission device, cooling to room temperature (adopting air cooling, wherein the cooling time is at least 1h) to obtain an initial product (see figure 1, the cross section of the formed aluminum material is in a shape of' ]);
3) bending and rolling the primary product into a round aluminum material with a specified specification by a rolling machine (see figure 2); the rolling machine adopts the two rollers of perpendicular setting to roll the primary product, and the below roller is the drive roll that links to each other with the motor, and the top is the driven voller, and motor 500: 1, driving a speed reducer to be in transmission connection with a roll shaft, and rolling the primary product by a double roll of a rolling machine at a rolling pressure of 1.2MPa for 4 times;
4) welding two end-to-end gaps of the round aluminum material, then cutting the section by a cutting machine, carrying out numerical control punching according to different specification requirements, and carrying out subsequent finish machining to obtain the product.
Specifically, the aluminum raw material is aluminum bar or aluminum ingot, wherein the aluminum content is 75 wt%, the aluminum purity is higher than 95%, the aluminum raw material also comprises boron, tungsten and magnesium, the boron content is 1 wt%, the tungsten content is 0.3 wt%, and the magnesium content is 1 wt%.
In the step 1), the preheating temperature is 460 ℃, and the heat preservation time is 10 min; in the step 1), the extrusion forming power of the plate mould is 50kW, the pressure is 300T, and the propelling speed is 0.5 m/min.
Example 5:
a manhole processing technology of a liquid storage tank comprises the following processing steps:
1) taking an aluminum raw material, preheating and preserving heat for a period of time, then continuously heating to 520 ℃, and pushing into a plate die for extrusion forming;
2) conveying the formed aluminum material discharged from a discharge hole at one side of the plate die to a heat dissipation area through a transmission device, cooling to room temperature (adopting air cooling, wherein the cooling time is at least 1h) to obtain an initial product (see figure 1, the cross section of the formed aluminum material is in a shape of' ]);
3) bending and rolling the primary product into a round aluminum material with a specified specification by a rolling machine (see figure 2); the rolling machine adopts the two rollers of perpendicular setting to roll the primary product, and the below roller is the drive roll that links to each other with the motor, and the top is the driven voller, and motor 500: 1, driving a speed reducer to be in transmission connection with a roll shaft, and rolling the primary product by a double roll of a rolling machine for 5 times under the rolling pressure of 1 MPa;
4) welding two end-to-end gaps of the round aluminum material, then cutting the section by a cutting machine, carrying out numerical control punching according to different specification requirements, and carrying out subsequent finish machining to obtain the product.
Specifically, the aluminum raw material is an aluminum bar or an aluminum ingot, wherein the aluminum content is 70 wt%, the aluminum purity is higher than 95%, the aluminum raw material also comprises boron, tungsten and magnesium, the boron content is 1 wt%, the tungsten content is 0.6 wt%, and the magnesium content is 2 wt%.
In the step 1), the preheating temperature is 450 ℃, and the heat preservation time is 10 min; the extrusion forming power of the panel mould in the step 1) is 50kW, the pressure is 290T, and the propelling speed is 0.5 m/min.
Through reasonable raw material selection and process and parameter improvement, the manufactured manhole welding bead is reduced by 90%, the airtight effect is good, the process period is effectively shortened, time and labor are saved, the manhole is integrally formed, the stability is strong, the comprehensive mechanical property is good, the cost is low, the operation is simple and convenient, and the industrial application is facilitated.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. The invention is limited only by the claims and their full scope and equivalents.
Claims (4)
1. A manhole processing technology of a liquid storage tank is characterized by comprising the following processing steps:
1) taking an aluminum raw material, preheating and preserving heat for a period of time, continuously heating to 500-550 ℃, pushing into a plate die, and carrying out extrusion forming, wherein the aluminum raw material is an aluminum bar or an aluminum ingot, the aluminum content is more than 65 wt%, the aluminum purity is more than 95%, the aluminum raw material also comprises boron, tungsten and magnesium, the boron content is less than 1.5 wt%, the tungsten content is less than 0.6 wt%, and the magnesium content is less than 2.5 wt%; preheating temperature is 450-; the extrusion molding power of the plate die is 48-50kW, the pressure is 290-300T, and the propelling speed is 0.45-0.55 m/min;
2) conveying the formed aluminum material discharged from a discharge hole at one side of the plate die to a heat dissipation area through a transmission device, and cooling to room temperature to obtain an initial product;
3) bending and rolling the primary product into a round aluminum material with specified specification by a rolling machine, wherein the rolling pressure of the rolling machine on the primary product is 1-1.5MPa, and the rolling times are 4-5 times;
4) welding two end-to-end gaps of the round aluminum material, then cutting the section by a cutting machine, carrying out numerical control punching according to different specification requirements, and carrying out subsequent finish machining to obtain the product.
2. The manhole processing technology of the liquid storage tank as claimed in claim 1, wherein: the section of the formed aluminum material in the step 2) is in a shape like a ']'.
3. The manhole processing technology of the liquid storage tank as claimed in claim 1, wherein: and (3) air cooling is adopted in the heat dissipation area in the step 2), and the cooling time is at least 1 h.
4. The manhole processing technology of the liquid storage tank as claimed in claim 1, wherein: step 3) medium-pressure rolling machine adopts the perpendicular two rollers that set up to roll the primary product, and the below roller is the drive roll that links to each other with the motor, and the top is the driven voller, and motor 500: the 1 drives a speed reducer to be connected with the roll shaft in a transmission way.
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| CN1099332C (en) * | 1998-09-28 | 2003-01-22 | 高志芳 | Method for manufacturing cap of container |
| US6379473B1 (en) * | 1999-05-28 | 2002-04-30 | Honda Giken Kogyo Kabushiki Kaisha | Method of manufacturing laminated ring using molten salt composition |
| CN102040059B (en) * | 2009-10-21 | 2012-05-02 | 西安轨道交通装备有限责任公司 | Tank car manhole and production process thereof |
| CN101972915B (en) * | 2010-08-04 | 2012-08-29 | 南京宝色股份公司 | Method for preparing corrosion-resistant non-ferrous metal pipeline |
| CN102672435A (en) * | 2012-05-28 | 2012-09-19 | 北京航星机器制造公司 | Integral forming method for thin-walled titanium alloy part with irregularly-shaped curved surface and die |
| CN104028598B (en) * | 2014-06-06 | 2016-04-20 | 中国航天科技集团公司长征机械厂 | A kind of bellows processing technology |
| CN104827243A (en) * | 2014-07-04 | 2015-08-12 | 巩宝钢 | Wheel rim manufacturing method and wheel rims |
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