CN113798801A - Forming method of thick helical blade - Google Patents
Forming method of thick helical blade Download PDFInfo
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- CN113798801A CN113798801A CN202111006729.6A CN202111006729A CN113798801A CN 113798801 A CN113798801 A CN 113798801A CN 202111006729 A CN202111006729 A CN 202111006729A CN 113798801 A CN113798801 A CN 113798801A
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- helical blade
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- helical
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- 238000000034 method Methods 0.000 title claims abstract description 43
- 239000000463 material Substances 0.000 claims abstract description 8
- 238000003466 welding Methods 0.000 claims abstract description 7
- 238000005520 cutting process Methods 0.000 claims description 8
- 229910000831 Steel Inorganic materials 0.000 claims description 4
- 239000010959 steel Substances 0.000 claims description 4
- 238000010008 shearing Methods 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 abstract description 23
- 238000005097 cold rolling Methods 0.000 abstract description 6
- 230000002349 favourable effect Effects 0.000 abstract description 3
- 238000012423 maintenance Methods 0.000 abstract description 2
- 238000005096 rolling process Methods 0.000 abstract 1
- 238000004364 calculation method Methods 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000005489 elastic deformation Effects 0.000 description 2
- 239000002699 waste material Substances 0.000 description 2
- 238000001514 detection method Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 239000002657 fibrous material Substances 0.000 description 1
- 210000001503 joint Anatomy 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 238000003892 spreading Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
- B23P15/04—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass turbine or like blades from several pieces
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
The invention discloses a forming method of a thick helical blade, which relates to the technical field of mechanical equipment maintenance and overhaul and comprises the following steps: a) calculating the shape and size of the helical blade; b) blanking to obtain a single blade; c) welding a required number of single blades together to form the spiral blade according to a given method; d) hoisting the helical blade and then performing stretch forming; e) excess material on the helical blade is sheared. The manufacturing method is simple, convenient and quick, can be quickly molded without special equipment, is convenient for manufacturing the helical blade with the thickness of more than 14mm, simplifies the manufacturing of the single thick helical blade by adopting a cold rolling and rolling process, reduces the manufacturing cost, shortens the purchasing period and avoids seriously influencing the production. The method is suitable for emergency, is convenient for quickly repairing equipment, and is favorable for quickly recovering production.
Description
Technical Field
The invention relates to the technical field of maintenance and overhaul of mechanical equipment, in particular to a forming method of a thick helical blade, which is used for quickly repairing the helical blade of a key component of a helical conveyor.
Background
At present, the screw conveyor is widely applied in various industries such as metallurgy, chemical industry, papermaking, light industry and the like, and the screw conveyor with the clean conveying function is more and more widely applied. During the use of screw conveyors, special scenarios are often encountered, such as: the metallurgical dust remover system just uses the humidification machine of unloading ash, and its host computer is screw conveyer really, and large-scale humidification machine of unloading ash often appears helical blade deformation, distortion because of adding water inhomogeneous, perhaps ash is inhomogeneous down, accidents such as main shaft fracture. Other special application scenes are involved, such as uneven flow of conveyed materials, small time and large time; for example, the conveyed material is not stable in humidity, for example, the conveyed material is not clean, fibrous materials are often mixed, and the like. In these cases, the helical blades may be deformed and twisted, and the main shaft may be broken.
In order to solve the problem, the spiral blade and the main shaft need to be modified, and the main shaft is thickened in a common method, and the thickness of the spiral blade is increased to more than 14mm, even 50mm under special conditions. The spiral blade of the spiral conveyor is generally formed by adopting a cold rolling winding forming method, blanking a flat plate and then cold rolling and coiling, and is suitable for mass production. However, the helical blade with the thickness of more than 14mm is less in use amount, and the single thick helical blade is manufactured by adopting a cold rolling process, so that the cost is high. Thick helical blades, once damaged, require custom-made. The normal purchasing process is as follows: and searching thick helical blade production enterprises and signing a contract. If no goods are available, the purchasing period can be long, less 10 days, more 1 month, which can cause long-time production halt and seriously affect production.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a forming method of a thick helical blade, which is simple, convenient and quick in manufacturing method, capable of forming quickly, free of special equipment, convenient for manufacturing the thick helical blade, simplified in manufacturing the single thick helical blade by adopting a cold rolling and coiling process and reduced in manufacturing cost. The purchasing period is shortened, and the production is seriously influenced by the wall surface. The method is suitable for emergency, is convenient for quickly repairing equipment, and is favorable for quickly recovering production.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
a method for forming a thick helical blade comprises the following steps: a) calculating the shape and size of the helical blade; b) blanking to obtain a single blade; c) welding a required number of single blades together to form the spiral blade according to a given method; d) hoisting the helical blade and then performing stretch forming; e) excess material on the helical blade is sheared.
The technical scheme of the invention is further improved as follows: in step d), the helical blade is vertically hoisted and then is subjected to stretch forming.
The technical scheme of the invention is further improved as follows: in step b), blanking according to the development length of the helical surface of one lead to obtain a single blade with the development length of one lead.
The technical scheme of the invention is further improved as follows: in step d), the stretching is stopped when the single lobe is stretched to reach 1.05 times the theoretical value of the lead.
The technical scheme of the invention is further improved as follows: in the step c), the single blade blank is pried along the radial direction CD cutting seam to enable the blade blank to be staggered up and down, then the single blades on the plurality of spiral surfaces are welded together in a staggered mode along the CD cutting seam in sequence, the obtained single blades are welded together in a staggered mode end to end in the spiral direction, and two surfaces of the joint of the single blades are all welded.
The technical scheme of the invention is further improved as follows: in step c), welding process connecting plates for drawing at the tail part of the last single blade or at the head and tail sides of the last single blade; in the step d), four hanging rings are symmetrically welded on the process connecting plate, and the steel wire ropes are respectively penetrated through the four hanging rings, so that the up-and-down tension is ensured to be opposite.
The technical scheme of the invention is further improved as follows: in step d), if the blade size is insufficient or the helical blade is not uniform, the helical blade is turned around and pulled again, and the helical blade is simultaneously hit by a hand hammer or a sledge hammer.
The technical scheme of the invention is further improved as follows: in step d), when the rigidity of the blade is relatively large, the whole spiral blade is heated.
The technical scheme of the invention is further improved as follows: in step c) or d), the helical blade is contacted with a supporting device, wherein the supporting device comprises a base, a supporting column arranged vertically, a first branch hinged on the supporting column, and a second branch hinged at the end of the first branch, and the end of the first branch or the second branch is contacted with the helical blade.
The technical scheme of the invention is further improved as follows: the position relation between the supporting device and the helical blade comprises that the supporting device is inserted in a helical channel enclosed in the helical blade, or two or more supporting devices are arranged around the helical blade, and the tail end of the first branch or the second branch of each supporting device is in contact with the helical blade.
Due to the adoption of the technical scheme, the invention has the technical progress that:
the invention ensures that the manufacturing method is simple, convenient and quick and can be quickly molded. The method does not need special equipment, is convenient for manufacturing the helical blade with the thickness of more than 14mm, simplifies the manufacture of the single thick helical blade by adopting a cold rolling process, and reduces the manufacturing cost. The purchasing period is shortened, and the production is seriously influenced by the wall surface. The method is suitable for emergency, is convenient for quickly repairing equipment, and is favorable for quickly recovering production.
The supporting device reduces vibration in the manufacturing process, prevents instability, prevents blades from being broken and increases stability.
And welding a process connecting plate for drawing on the tail part of the last single blade or the head and tail sides of the last single blade, so that the material waste caused by large deformation of the last single blade is prevented.
In the step d), when the rigidity of the blade is higher, the whole blade is heated to improve the plasticity, so that the effect of uniform shape can be obtained, and the product quality is improved.
Drawings
FIG. 1 is a schematic diagram of the apparatus of the present invention;
FIG. 2 is a development of the inner and outer helical lines of the helical blade of the present invention;
FIG. 3 is a schematic view of the calculation of the fan angle number and the outer helix development length of the helical blade of the present invention;
FIG. 4 is a schematic view of the inventive helical blade under force;
FIG. 5 is a schematic diagram of the device structure of another form of the invention;
FIG. 6 is a schematic view of another perspective of FIG. 5;
the device comprises a support column, a lifting ring, 2, a spiral blade, 4, a base, 5, a roller, 7, a support column lower section, 8, a support column upper section, 9, a first branch, 10 and a second branch.
Detailed Description
The present invention will be described in further detail with reference to the following examples:
as shown in fig. 1 to 6, a method for forming a thick helical blade includes the steps of:
a) calculating the shape and size of the sheet metal spread of the helical blade:
a1, calculating the expansion length of the inner spiral line and the outer spiral line of the spiral blade:
as shown in figure 2, according to the known conditions, the inner diameter D of the helical blade, the outer diameter D of the helical blade and the helical pitch of the lead H are made into a right triangle, one square edge is equal to the lead H, the other square edge is respectively inner, the projection length pi D of the outer helical line is shown in figure 2, and pi D is shown in figure 2.
1. Determining the developed length of the internal helical line
2. Determining the developed length of the internal helical line
a2, calculating the opening angle of the single external helical blade after expansion
As shown in fig. 3, when the spiral blade is manufactured, to contract inward, a notch needs to be cut from the outer circle, and the central angle corresponding to the notch is β. The outer circle radius R and the inner circle radius R of the outer helical blade blanking round blank are set to obtain the length of the whole circumferential arc of 2 pi R, and the length is pushed out
Beta: for cutting out the angle degree of the fan
L2: for the extended length of the external spiral
The value of beta corresponding to the empirical central angle is determined by the helix outside diameter D and the lead H,
a3, calculating the inner radius and the outer radius of the circular blanking after the single helical blade is unfolded
In order to avoid secondary processing and cause serious process waste during the self-control of the helical blade, the key lies in the size determination of the outer diameter and the inner diameter of the circular ring blank after the helical blade is unfolded during blanking. Knowing the value of the central angle beta and the length L of the helix developed in the blade1Length L of the outer spiral2And respectively calculating the inner radius R and the outer radius R of the spiral blade unfolded blanking round blank.
The value of the opening angle beta of the unfolded helical blade is as follows: push button
This indicates that the β value varies with the relationship between H and D.
According to
It can be derived that:
the same can be obtained:
and counting the number of required single blades according to the length of the original spiral shaft by referring to a metal plate unfolding calculation method of a conventional spiral blade and calculating according to the unfolding blanking of a spiral surface of one lead.
b) Blanking of thick helical blades to obtain single blades:
the sheet metal spreading calculation method of the conventional helical blade is referred, the blanking is spread according to a helical surface of a lead, a small fan-shaped notch with a central angle beta is not needed to be removed, and a seam CD is directly cut along the radius direction to obtain a single blade. Counting the number of required single blades according to the length of the original spiral shaft, and then, arranging a blank ring of spiral blades with a specified number according to the method, and cutting a seam CD along the radius direction.
c) A plurality of individual blades are welded to form the helical blade 2 and prepared for stretching:
and (3) prying the single blade blank along the radial direction CD cutting seam by adopting a proper tool to make the single blade blank staggered up and down, and then welding the single blades of the plurality of helicoids together in sequence along the CD cutting seam in a staggered manner. The obtained blades are welded end to end in a staggered mode in the spiral direction, and two faces of the butt joint of the single blades are all welded.
In order to prevent the last single blade from deforming greatly and being discarded, a process connecting plate for drawing is welded on the tail part of the last single blade or the head and the tail sides of the last single blade.
d) The stress state of the thicker blade is shown in fig. 4, a series of blades formed by combining a process connecting plate and a plurality of single blades are symmetrically welded with four hanging rings 1 on the process connecting plate, and steel wire ropes are respectively penetrated into the four hanging rings 1, so that the condition that the upper and lower tension forces are right and the shearing force cannot be generated is ensured. The welded helical blade 2 is subjected to stretch forming after vertical hoisting, tools such as a chain block and a travelling crane are used for pulling a steel wire rope connected with a hoisting ring in the stretching process, an even stretching force is given to the helical blade 2, the lead is gradually increased along with continuous stretching of the blade, and the stretching is stopped when a single blade is stretched to reach 1.05 times of the theoretical value of the lead. And then the helical blades 2 are unloaded for size detection, if the sizes of the individual blades are insufficient or uneven, the helical blades 2 are turned around and pulled again, and meanwhile, a hand hammer or a sledge hammer can be used for knocking, so that the elastic deformation is forced to be plastic deformation, and the phenomenon that the elastic deformation is over-bent due to stretching is avoided. When the rigidity of the blade is higher, the whole blade is heated to improve the plasticity, and the effect of uniform shape can be obtained.
e) The excess material on the screw blade 2 is sheared, mainly by removing the process connection plate.
In step c or d, the support means are used in contact with the helical blade 2. The supporting device comprises a base 4, a vertically arranged supporting column, a first branch 9, a second branch 10 and a spiral blade 2, wherein the first branch 9 is hinged on the supporting column, the second branch 10 is hinged at the tail end of the first branch 9, and the tail end of the first branch 9 or the tail end of the second branch 10 is in contact with the spiral blade 2. The bottom of base 4 is provided with gyro wheel 5, and the support column includes support column hypomere 7 and support column upper segment 8, and the support column is inside to be provided with hydraulic means, and hydraulic means is ejecting 8 upwards with support column upper segment. The first branches 9 are disposed on the outer side wall surface of the support column upper section 8, and the first branches 9 are uniformly distributed along the circumference of the outer side wall surface of the support column upper section 8, and generally, four first branches 9 are disposed. The upper section 8 of the supporting column is provided with a groove which is matched with the first branch 9 and the second branch 10, and when the supporting column is not used, the first branch 9 and the second branch 10 are retracted and placed in the groove. The first branch 9 and the second branch 10 may be provided with hydraulic control or may be simply manually actuated to control their positions.
The position relationship between the supporting device and the helical blade 2 is at least two, one is that the supporting device is inserted in a helical channel enclosed by the helical blade 2, as shown in fig. 1. The second is that two or more support means are arranged around the helical blade 2, the end of the first branch 9 or the second branch 10 of each support means being in contact with the helical blade 2, as shown in fig. 5 and 6.
Claims (10)
1. A method for forming a thick helical blade is characterized in that: the method comprises the following steps: a) calculating the shape and size of the helical blade; b) blanking to obtain a single blade; c) welding the required number of single blades together to form the helical blade (2) according to a given method; d) hoisting the helical blade and then performing stretch forming; e) shearing the excess material on the helical blade (2).
2. A method of forming a thick helical blade according to claim 1, wherein: in the step d), the helical blade (2) is vertically hoisted and then is stretched and formed.
3. A method of forming a thick helical blade according to claim 1, wherein: in step b), blanking according to the development length of the helical surface of one lead to obtain a single blade with the development length of one lead.
4. A method of forming a thick helical blade according to claim 3, wherein: in step d), the stretching is stopped when the single lobe is stretched to reach 1.05 times the theoretical value of the lead.
5. A method of forming a thick helical blade according to claim 3, wherein: in the step c), the single blade blank is pried along the radial direction CD cutting seam to enable the blade blank to be staggered up and down, then the single blades on the plurality of spiral surfaces are welded together in a staggered mode along the CD cutting seam in sequence, the obtained single blades are welded together in a staggered mode end to end in the spiral direction, and two surfaces of the joint of the single blades are all welded.
6. A method of forming a thick helical blade according to claim 3, wherein: in step c), welding process connecting plates for drawing at the tail part of the last single blade or at the head and tail sides of the last single blade; in the step d), four hanging rings (1) are symmetrically welded on the process connecting plate, and steel wire ropes are respectively penetrated through the four hanging rings (1) to ensure that the up-and-down tension is just opposite.
7. A method of forming a thick helical blade according to claim 3, wherein: in step d), if the blade size is insufficient or the helical blade (2) is not uniform, the helical blade (2) is turned around and pulled again, and the helical blade (2) is knocked by a hand hammer or a sledge hammer.
8. A method of forming a thick helical blade according to claim 1, wherein: in step d), when the blade rigidity is relatively high, the helical blade (2) is heated integrally.
9. A method of forming a thick helical blade according to claim 1, wherein: in step c) or d), the helical blade (2) is contacted using a support device comprising a base (4), a vertically arranged support column, a first branch (9) hinged on the support column, a second branch (10) hinged at the end of the first branch (9), the end of the first branch (9) or the second branch (10) being contacted with the helical blade (2).
10. A method of forming a thick helical blade according to claim 9, wherein: the position relation between the supporting device and the helical blade (2) comprises that the supporting device is inserted in a helical channel enclosed in the helical blade (2), or two or more supporting devices are arranged around the helical blade (2), and the tail end of the first branch (9) or the second branch (10) of each supporting device is in contact with the helical blade (2).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111006729.6A CN113798801A (en) | 2021-08-30 | 2021-08-30 | Forming method of thick helical blade |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111006729.6A CN113798801A (en) | 2021-08-30 | 2021-08-30 | Forming method of thick helical blade |
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| CN113798801A true CN113798801A (en) | 2021-12-17 |
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| CN202111006729.6A Pending CN113798801A (en) | 2021-08-30 | 2021-08-30 | Forming method of thick helical blade |
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1119135A (en) * | 1994-09-23 | 1996-03-27 | 黑龙江省宾西水泥厂 | Method for manufacturing screw blades and stretching machine for screw blades |
| CN101259512A (en) * | 2008-04-18 | 2008-09-10 | 李悦 | Forming method of spiral subsection blade |
| CN101386121A (en) * | 2008-10-31 | 2009-03-18 | 镇江华晨华通路面机械有限公司（中外合资） | Spiral feeding blade manufacture method and device |
| CN101456044A (en) * | 2008-12-30 | 2009-06-17 | 天津博瑞康机械制造有限公司 | Production method of helical discharging sedimentation centrifuge helical blade |
| CN101817446A (en) * | 2010-04-01 | 2010-09-01 | 聂俊 | Thickness-equaling and optimizing technology of spiral screw and manufacture technology |
| CN202963990U (en) * | 2012-11-08 | 2013-06-05 | 鲁西工业装备有限公司 | Screw conveying rod producing device |
| CN203030699U (en) * | 2012-11-26 | 2013-07-03 | 郑州正弘桩工机械制造有限公司 | Spiral blade stretch forming machine |
| CN104772609A (en) * | 2015-04-22 | 2015-07-15 | 柳州凡一科技有限公司 | Grain conveyer auger blade processing method |
| CN204549232U (en) * | 2015-04-02 | 2015-08-12 | 福建南方路面机械有限公司 | A kind of spliced abrasion-proof helical blade |
| CN211515779U (en) * | 2019-12-25 | 2020-09-18 | 余姚市浙东给排水设备有限公司 | Helical blade forming machine |
-
2021
- 2021-08-30 CN CN202111006729.6A patent/CN113798801A/en active Pending
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1119135A (en) * | 1994-09-23 | 1996-03-27 | 黑龙江省宾西水泥厂 | Method for manufacturing screw blades and stretching machine for screw blades |
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| CN101386121A (en) * | 2008-10-31 | 2009-03-18 | 镇江华晨华通路面机械有限公司（中外合资） | Spiral feeding blade manufacture method and device |
| CN101456044A (en) * | 2008-12-30 | 2009-06-17 | 天津博瑞康机械制造有限公司 | Production method of helical discharging sedimentation centrifuge helical blade |
| CN101817446A (en) * | 2010-04-01 | 2010-09-01 | 聂俊 | Thickness-equaling and optimizing technology of spiral screw and manufacture technology |
| CN202963990U (en) * | 2012-11-08 | 2013-06-05 | 鲁西工业装备有限公司 | Screw conveying rod producing device |
| CN203030699U (en) * | 2012-11-26 | 2013-07-03 | 郑州正弘桩工机械制造有限公司 | Spiral blade stretch forming machine |
| CN204549232U (en) * | 2015-04-02 | 2015-08-12 | 福建南方路面机械有限公司 | A kind of spliced abrasion-proof helical blade |
| CN104772609A (en) * | 2015-04-22 | 2015-07-15 | 柳州凡一科技有限公司 | Grain conveyer auger blade processing method |
| CN211515779U (en) * | 2019-12-25 | 2020-09-18 | 余姚市浙东给排水设备有限公司 | Helical blade forming machine |
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Application publication date: 20211217 |
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