CN115781196A - Cold machining process for pipe fitting elbow structure - Google Patents
Cold machining process for pipe fitting elbow structure Download PDFInfo
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- CN115781196A CN115781196A CN202211608573.3A CN202211608573A CN115781196A CN 115781196 A CN115781196 A CN 115781196A CN 202211608573 A CN202211608573 A CN 202211608573A CN 115781196 A CN115781196 A CN 115781196A
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- steel pipe
- elbow
- pipe
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Abstract
The invention discloses a cold machining process for a pipe fitting elbow structure, which comprises the following steps: s1, cutting a steel pipe: the method comprises the following steps of cutting the steel pipe in equal length through a laser cutting machine, and cutting the steel pipe in an inclined manner by adopting an inclined angle cutting mode; s2, filling a steel pipe; this application sets up through the laser cutting machine slope that will cut the steel pipe, and make this laser cutting machine can carry out height and angle modulation, thereby make the processing of elbow can carry out the change of size, simultaneously at the both ends and the middle part of steel pipe do not supporting through the centre gripping instrument of setting for and specific filler, can guarantee like this that the steel pipe is in the bending, can carry out a bending according to the setting for of filler, local collapse can not appear in the elbow inside of guaranteeing to produce out, the condition of direct rupture can not appear in the crooked outside of elbow simultaneously, the centre gripping instrument can make things convenient for the dismantlement of elbow and support the both ends of elbow simultaneously, guarantee the quality of elbow when producing.
Description
Technical Field
The invention belongs to the technical field of pipe fitting elbow processing, and particularly relates to a cold machining process for a pipe fitting elbow structure.
Background
The elbow can be formed by pushing one section of short pipe, the cold machining process of the elbow structure of the pipe fitting refers to stamping elbow, the seamless elbow batch production is the earliest forming process, the hot pushing method or other forming processes are used for replacing the common specification elbow production, but in some specifications, the yield is small, and the wall thickness is too thick or too thin. The product is still used when special requirements exist, the elbow stamping forming adopts a pipe blank with the same outer diameter as the elbow, the pipe blank is directly pressed and formed in a die by a press machine, before stamping, the pipe blank is placed on a lower die, an inner core and an end die are loaded into the pipe blank, an upper die moves downwards and starts to press downwards, and the elbow is formed through the restraint of an outer die and the support of an inner die.
In current pipe fitting elbow processing technology process, at first through putting into elbow stamping forming professional hydraulic press with the steel pipe, utilize the hydraulic press to carry out the in-process that punches to the elbow, because the inside of steel pipe lacks the fixed stay subassembly of joining in marriage, and then can lead to the steel pipe to be in the in-process of punching press one-tenth elbow, can cause the local of elbow to appear damaging, also can lead to the quality of elbow relatively poor simultaneously, the elbow quality level of producing is uneven.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a cold machining process for a pipe fitting elbow structure, which enables a laser cutting machine to adjust the height and the angle, so that the machining of an elbow can change the size, meanwhile, the two ends and the middle part of a steel pipe are respectively supported by a set clamping tool and a specific filler, thus the steel pipe can be ensured to be bent according to the setting of the filler when being bent, the situation that the inside of the produced elbow is locally collapsed is ensured not to occur, meanwhile, the outer side of the bent elbow is not directly broken off is ensured, meanwhile, the clamping tool can facilitate the disassembly of the elbow and support the two ends of the elbow, and the quality of the elbow in production is ensured. .
In order to achieve the purpose, the invention provides the following technical scheme: a cold machining process for a pipe fitting elbow structure comprises the following machining process steps:
s1, cutting a steel pipe: the method comprises the following steps of cutting the steel pipe in equal length through a laser cutting machine, and cutting the steel pipe in an inclined manner by adopting an inclined angle cutting mode;
s2, filling a steel pipe: filling the middle part of the inner cavity of the steel pipe, and filling and supporting the inner cavity of the steel pipe through the set bent steel;
s3, positioning the steel pipe: clamping two ends of the steel pipe through a specific clamping tool, and filling inner cavities at two ends of the steel pipe;
s4, stamping the steel pipe: the steel pipe clamped on the lower die is punched and formed by using a hydraulic press special for the elbow to form the elbow;
s5, taking out the steel pipe: and taking out the steel pipe subjected to press forming from the lower die, taking out the filling piece in the steel pipe, and taking out the clamping tools from two ends of the steel pipe.
The four-column hydraulic press is a special equipment for manufacturing the elbow, the stainless steel elbow is a pipe for changing the direction of a pipeline, and has the advantages of light weight, good corrosion resistance and good heat preservation performance, generally three types of 45 degrees, 90 degrees and 180 degrees are commonly used, the four-column hydraulic press is a main equipment for forming the stamping elbow, and the machine can be simultaneously suitable for forming processes of various materials such as cast iron elbows, stainless steel elbows, alloy steel elbows, malleable cast iron elbows, carbon steel elbows, elbows made of nonferrous metals and the like. The elbow forming four-column hydraulic press series products are provided with independent power mechanisms and electric systems, are controlled by buttons in a centralized manner, are adjusted, manually operated and semi-automatically operated by relays or PLC programmable controllers in process actions, and can be adjusted according to process requirements in working pressure and stroke ranges.
The performance characteristics of the elbow punch forming four-column hydraulic press are as follows:
the computer optimizes the structural design, and the four-column structure is simple, economic and practical; the frame structure has good rigidity, high precision and strong unbalance loading resistance.
The hydraulic control adopts a plug-in type basic system, the action is reliable, the service life is long, the hydraulic impact is small, and connecting pipelines and leakage points are reduced.
The electrical system controlled by the PLC has the advantages of compact structure, sensitive and reliable work and good flexibility.
The device has three operation modes of adjustment, single circulation of both hands and continuous work (with a feeding device).
Through the selection of the operation panel, not only can two forming processes of fixed distance and fixed pressure be realized, but also three process working cycles of cushion, cushion-free and ejection can be realized.
Preferably, the steel pipe is cut by a pair of laser cutting machines, the two laser cutting machines are arranged in an inclined symmetrical mode, the height of the steel pipe can be adjusted, the laser cutting machines are used for cutting the steel pipe in equal length, and the two laser cutting machines are used for cutting the steel pipe in equal length alternately.
Preferably, the steel pipe is filled with the filler, the filler is placed in the steel pipe, the middle part of the steel pipe is supported, the filler is matched with the bending form of the steel pipe, and the filler can be separated from the steel pipe.
Preferably, the steel pipe is positioned by fixing two ends of the steel pipe through a clamping tool, the butt joint end of the clamping tool and the steel pipe is set to be cylindrical, the clamping end of the clamping tool is inserted into the steel pipe, the steel pipe can be supported while the steel pipe is fixed, and the outer diameter of the clamping tool is matched with the inner diameter of the steel pipe.
Preferably, when the steel pipe is punched, the steel pipe is placed on the lower die through the clamping tool, then the upper die is pulled through the hydraulic press to punch the steel pipe, so that the steel pipe is bent to enter the lower die, and then the upper die and the lower die are extruded to punch the steel pipe.
Preferably, the steel pipe is taken out from the lower die by the clamping tool, and then the supporting block in the steel pipe is taken out by jacking the jacking rod, so that the next steel pipe is supported for use.
Compared with the prior art, the invention has the following beneficial effects:
this application sets up through the laser cutting machine slope that will cut the steel pipe, and make this laser cutting machine can carry out height and angle modulation, thereby make the processing of elbow can carry out the change of size, simultaneously at the both ends and the middle part of steel pipe do not supporting through the centre gripping instrument of setting for and specific filler, can guarantee like this that the steel pipe is in the bending, can carry out a bending according to the setting for of filler, local collapse can not appear in the elbow inside of guaranteeing to produce out, the condition of direct rupture can not appear in the crooked outside of elbow simultaneously, the centre gripping instrument can make things convenient for the dismantlement of elbow and support the both ends of elbow simultaneously, guarantee the quality of elbow when producing.
Drawings
FIG. 1 is a process flow diagram of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention provides a technical scheme that: a cold machining process for a pipe fitting elbow structure comprises the following machining process steps:
s1, cutting a steel pipe: the method comprises the following steps of cutting the steel pipe in equal length through a laser cutting machine, and cutting the steel pipe in an inclined manner by adopting an inclined angle cutting mode;
s2, filling a steel pipe: filling the middle part of the inner cavity of the steel pipe, and filling and supporting the inner cavity of the steel pipe through set bent steel;
s3, positioning the steel pipe: clamping two ends of the steel pipe through a specific clamping tool, and filling inner cavities at two ends of the steel pipe;
s4, stamping the steel pipe: the steel pipe clamped on the lower die is punched and formed by using a hydraulic press special for the elbow to form the elbow;
s5, taking out the steel pipe: and taking out the steel pipe subjected to the press forming from the lower die, taking out the filling piece in the steel pipe, and taking out the clamping tools from two ends of the steel pipe.
The four-column hydraulic press is a special equipment for manufacturing the elbow, the stainless steel elbow is a pipe for changing the direction of a pipeline, and has the advantages of light weight, good corrosion resistance and good heat preservation performance, generally three types of 45 degrees, 90 degrees and 180 degrees are commonly used, the four-column hydraulic press is a main equipment for forming the stamping elbow, and the machine can be simultaneously suitable for forming processes of various materials such as cast iron elbows, stainless steel elbows, alloy steel elbows, malleable cast iron elbows, carbon steel elbows, elbows made of nonferrous metals and the like. The elbow forming four-column hydraulic press has independent power mechanism and electric system, and adopts button centralized control, and the technological action adopts relay or PLC programmable controller to implement regulation, manual operation and semi-automatic operation, and its working pressure and stroke range can be regulated according to the technological requirements.
The performance characteristics of the elbow punch forming four-column hydraulic press are as follows:
the computer optimizes the structural design, and the four-column structure is simple, economic and practical; the frame structure has good rigidity, high precision and strong unbalance loading resistance.
The hydraulic control adopts a plug-in type basic system, the action is reliable, the service life is long, the hydraulic impact is small, and connecting pipelines and leakage points are reduced.
The electrical system controlled by the PLC has the advantages of compact structure, sensitive and reliable work and good flexibility.
Has three operation modes of adjustment, double-hand single circulation and continuous work.
Through the selection of the operation panel, not only can two forming processes of fixed distance and fixed pressure be realized, but also three process working cycles of cushion, cushion-free and ejection can be realized.
Wherein, the steel pipe cuts and goes on through a pair of laser cutting machine to the steel pipe, sets up two laser cutting machine slope symmetries to can adjust its height, utilize laser cutting machine to carry out the cutting of equidimension to the steel pipe, two laser cutting machine equidimension turn-by-turn are cut the steel pipe.
Laser cutting of pipes and profiles is performed by a combination of rotational and longitudinal movement of the workpiece relative to the laser cutting head. A burr-free and smooth cut end face in laser cutting can only be obtained if the desired distance between the nozzle and the workpiece is maintained with high precision at each tube position. If the laser cutting head is additionally pivoted by means of a tilting axis, it is possible to produce not only a perpendicular cutting end face but also a groove cut. This makes possible particularly complex profiles and intelligent plug connections of a plurality of steel, stainless steel or light and non-ferrous metal workpieces. The wall thickness can reach 15mm, and the length of pipe or section bar is only restricted by laser system size, therefore laser cutting machine can carry out the regulation of height and angle simultaneously, makes laser cutting machine can carry out the regulation of height according to the diameter of steel pipe, adjusts laser cutting machine's inclination according to the angle of elbow to make laser cutting machine can adapt to multiple operating mode.
Wherein, the inside of steel pipe is placed with the filler to the steel pipe packing, supports the middle part of steel pipe, makes the filler and the form looks adaptation of buckling of steel pipe, and the filler can break away from in the inside of steel pipe.
When filling the middle part of steel pipe through the filler, what at first considered is the support to the steel pipe middle part, and guarantee that the steel pipe can be smooth after crooked takes out from the steel pipe, and the shape of filling the supporting shoe will with the shape looks adaptation of steel pipe, guarantee that the steel pipe can be crooked to the radian of settlement, and make the steel pipe can not produce excessive dragging when crooked, excessive dragging can cause the drawing of steel pipe outside curved surface to split, inboard excessive extrusion can cause the inboard thickness of steel pipe to pile up, and then cause the steel pipe lateral surface to be too thin, the inboard thickness of steel pipe is too thick, consequently the crookedness of steel pipe and the shape of filler will the looks adaptation and guarantee that the steel pipe can not appear damaging at crooked in-process.
Wherein, the steel pipe location is fixed the both ends of steel pipe through clamping tool, sets the butt joint end of clamping tool and steel pipe to cylindrically to insert the inside of steel pipe with clamping tool's exposed core, can support the steel pipe when fixing the steel pipe, make clamping tool's external diameter and the internal diameter looks adaptation of steel pipe.
Its both ends of steel pipe centre gripping instrument here are the handle, be cylindricly in the one end with the steel pipe contact, and the internal diameter looks adaptation of cylindric external diameter and steel pipe, insert the both ends of steel pipe through the cylinder with the centre gripping instrument bottom, and then carry out the centre gripping to the steel pipe, support the both ends of steel pipe through cylindric centre gripping instrument simultaneously, guarantee that the steel pipe can keep the both ends of steel pipe when being bent by the pressure, make the both ends of steel pipe keep cylindricly, make the steel pipe can keep the shape of settlement in the bending.
When the steel pipe is stamped, the steel pipe is placed on the lower die through the clamping tool, then the upper die is drawn by the hydraulic press to stamp the steel pipe, so that the steel pipe is bent to enter the lower die, and then the upper die and the lower die are used for extrusion to further stamp and form the steel pipe.
The stamping is completed by a stamping die and stamping equipment, the high-speed pressure reaches hundreds of times or even more than thousands of times per minute, and each stamping stroke can obtain a stamping part, so the stamping has high production efficiency, convenient operation, easy realization of mechanization and automation, generally no generation of chips and crushed materials during stamping, less material consumption, no need of other heating equipment and lower cost of the stamping part, therefore, the stamping is a material-saving and energy-saving processing method, the size and shape precision of the stamping part are ensured by a die during stamping, the surface quality of the stamping part is generally not damaged, the service life of the die is generally longer, the stamping quality is stable, the interchangeability is good, and the stamping die has the characteristics of being the same as the stamping die.
When the hydraulic press special for the elbow pulls the upper die to punch the steel pipe in the lower die, the steel pipe is firstly placed in the lower die matched with the outer diameter of the steel pipe, then the top of the steel pipe is punched through the upper die, so that the steel pipe is bent to enter the lower die, clamping tools at two ends of the steel pipe can upwards tilt along with the bending of the steel pipe, and the steel pipe is taken out in a later period conveniently.
When the steel pipe is taken out, the steel pipe is taken down from the lower die through the clamping tool, then the supporting block in the steel pipe is jacked down through the jacking rod and taken out, so that the next steel pipe is supported for use, after the steel pipe is taken out flatly, the steel pipe is subjected to surface treatment, and then the steel pipe is packaged and put in storage.
When taking out the elbow from the lower mould, through lifting up the centre gripping instrument at elbow both ends, and then take out the elbow from the lower mould, then take out from the both ends of elbow between the centre gripping instrument, and then can make things convenient for the filler at elbow middle part to take out, the filler receives the extrusion of elbow inner wall at the middle part of elbow this moment, and then can not directly pour the filler out from the inside of elbow, need be ejecting through the inside filler of ejector pin with the elbow, and then can fill the support to next steel pipe with this filler.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (6)
1. A cold working process for a pipe fitting elbow structure is characterized in that: the processing technology comprises the following steps:
s1, cutting a steel pipe: the method comprises the following steps of cutting the steel pipe in equal length through a laser cutting machine, and cutting the steel pipe in an inclined manner by adopting an inclined angle cutting mode;
s2, filling a steel pipe: filling the middle part of the inner cavity of the steel pipe, and filling and supporting the inner cavity of the steel pipe through set bent steel;
s3, positioning the steel pipe: clamping two ends of the steel pipe through a specific clamping tool, and filling inner cavities at two ends of the steel pipe;
s4, stamping the steel pipe: the steel pipe clamped on the lower die is punched and formed by using a hydraulic press special for the elbow to form the elbow;
s5, taking out the steel pipe: and taking out the steel pipe subjected to the press forming from the lower die, taking out the filling piece in the steel pipe, and taking out the clamping tools from two ends of the steel pipe.
2. A cold working process for pipe elbow structures according to claim 1, characterised in that: the steel pipe is cut through a pair of laser cutting machines, the two laser cutting machines are arranged in a tilted symmetrical mode, the height of the steel pipe can be adjusted, the laser cutting machines are used for cutting the steel pipe in equal length, and the two laser cutting machines cut the steel pipe in equal length alternately.
3. A cold working process for pipe elbow structures according to claim 1, characterised in that: the steel pipe filling part is placed in the steel pipe, the middle part of the steel pipe is supported, the filler is matched with the bending form of the steel pipe, and the filler can be separated from the steel pipe.
4. The cold working process for pipe elbow structures according to claim 1, wherein: the steel pipe location is fixed the both ends of steel pipe through clamping tool, sets the butt joint end of clamping tool and steel pipe to cylindrically to insert the inside of steel pipe with clamping tool's exposed core, can support the steel pipe when fixing the steel pipe, make clamping tool's external diameter and the internal diameter looks adaptation of steel pipe.
5. The cold working process for pipe elbow structures according to claim 1, wherein: when the steel pipe is stamped, the steel pipe is placed on the lower die through the clamping tool, then the upper die is pulled through the hydraulic press to stamp the steel pipe, the steel pipe is bent to enter the lower die, and then the upper die and the lower die are used for extrusion so as to stamp and form the steel pipe.
6. A cold working process for pipe elbow structures according to claim 1, characterised in that: when the steel pipe is taken out, the steel pipe is taken down from the lower die through the clamping tool, and then the supporting block in the steel pipe is jacked down through the jacking rod and taken out, so that the next steel pipe is supported for use.
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CN202211608573.3A CN115781196A (en) | 2022-12-14 | 2022-12-14 | Cold machining process for pipe fitting elbow structure |
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CN202211608573.3A CN115781196A (en) | 2022-12-14 | 2022-12-14 | Cold machining process for pipe fitting elbow structure |
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Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101181727A (en) * | 2007-12-06 | 2008-05-21 | 浙江飞挺管业有限公司 | Process for making stainless steel thin-wall seamless elbows |
CN102430626A (en) * | 2011-11-23 | 2012-05-02 | 吉林昊宇电气股份有限公司 | Thin-wall equant (small)-radius elbow secondary forming device and secondary forming method thereof |
CN103978078A (en) * | 2014-05-16 | 2014-08-13 | 张明光 | Bending device and bending method for thin-walled tube |
CN107363138A (en) * | 2017-08-17 | 2017-11-21 | 燕山大学 | Elbow with straight section die forming method |
CN108817194A (en) * | 2018-04-28 | 2018-11-16 | 河南兴迪锻压设备制造有限公司 | A kind of more swan necks prepare mold and its hydraulic preparation method |
CN208408266U (en) * | 2018-06-06 | 2019-01-22 | 河北沧海核装备科技股份有限公司 | A kind of device for control elbow-punching forming |
CN111822563A (en) * | 2020-07-22 | 2020-10-27 | 芜湖市夯福机械模具有限公司 | Pipe elbow punch forming die |
CN216705590U (en) * | 2022-01-15 | 2022-06-10 | 胡雨卿 | Seamless stamping elbow die |
-
2022
- 2022-12-14 CN CN202211608573.3A patent/CN115781196A/en active Pending
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101181727A (en) * | 2007-12-06 | 2008-05-21 | 浙江飞挺管业有限公司 | Process for making stainless steel thin-wall seamless elbows |
CN102430626A (en) * | 2011-11-23 | 2012-05-02 | 吉林昊宇电气股份有限公司 | Thin-wall equant (small)-radius elbow secondary forming device and secondary forming method thereof |
CN103978078A (en) * | 2014-05-16 | 2014-08-13 | 张明光 | Bending device and bending method for thin-walled tube |
CN107363138A (en) * | 2017-08-17 | 2017-11-21 | 燕山大学 | Elbow with straight section die forming method |
CN108817194A (en) * | 2018-04-28 | 2018-11-16 | 河南兴迪锻压设备制造有限公司 | A kind of more swan necks prepare mold and its hydraulic preparation method |
CN208408266U (en) * | 2018-06-06 | 2019-01-22 | 河北沧海核装备科技股份有限公司 | A kind of device for control elbow-punching forming |
CN111822563A (en) * | 2020-07-22 | 2020-10-27 | 芜湖市夯福机械模具有限公司 | Pipe elbow punch forming die |
CN216705590U (en) * | 2022-01-15 | 2022-06-10 | 胡雨卿 | Seamless stamping elbow die |
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