CN115870704A - Internal expansion cold machining process for equal-diameter tee joint of pipe fitting - Google Patents
Internal expansion cold machining process for equal-diameter tee joint of pipe fitting Download PDFInfo
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- CN115870704A CN115870704A CN202211608547.0A CN202211608547A CN115870704A CN 115870704 A CN115870704 A CN 115870704A CN 202211608547 A CN202211608547 A CN 202211608547A CN 115870704 A CN115870704 A CN 115870704A
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Abstract
The invention discloses an internal expansion cold machining process of a pipe fitting equal-diameter tee joint, belonging to the technical field of metal machining processes, and comprising the following steps: blanking, namely calculating the blanking specification of a pipe blank according to the forming size of a three-way pipe fitting to be produced to select the pipe blank, wherein the surface of the pipe blank needs to be cleaned in advance and kept dry when a mould is selected, and the pipe blank is fixed in a three-way water expansion forming machine, and the periphery of the mould needs to be cleaned in advance to keep the integral cleaning degree when the mould is fixed; this application does benefit to through adopting the water bloated make-up machine and provides sufficient pressure, and liquid adopts the white emulsified water that easy mobility heat dispels soon, does benefit to the transmission efficiency who improves the medium, adopts laser cutting equipment, comes the cutting that is used for product or pipe embryo, does benefit to the efficiency that improves the cutting, improves the quality of cutting, and the accurate degree of further improvement cutting does benefit to the aesthetic measure that further improve equipment used.
Description
Technical Field
The invention belongs to the technical field of metal processing, and particularly relates to an internal expansion cold processing technology of a pipe equal-diameter tee joint.
Background
The production process of the three-way pipe is generally divided into two processes, namely an internal expansion cold working process, also called a hydraulic expansion process and a hot press forming process, wherein the forming materials suitable for the hydraulic expansion process are low carbon steel, low alloy steel and stainless steel with relatively low cold work hardening tendency, and comprise some nonferrous materials such as copper, aluminum, titanium and the like, so that the three-way pipe can be widely used.
In the existing internal expansion cold processing technology of the pipe equal-diameter tee joint, in order to reduce production cost, a hydraulic expanding machine is generally adopted in an expanding process, and meanwhile, a process flow is reduced, but in an actual use process, the reduction of the process flow and unreasonable equipment use often cause that insufficient pressure occurs in a product in a forming process to cause the tee joint to often have the condition of abnormal depression of the product, the condition causes that the yield is relatively low, the production cost is relatively high, meanwhile, the surface of the product also often has the condition of cracks, and in order to avoid the condition, the internal expansion cold processing technology of the pipe equal-diameter tee joint needs to be designed.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides an internal expansion cold machining process of a pipe fitting constant-diameter tee joint, which has the advantage of relatively high yield.
In order to achieve the purpose, the invention provides the following technical scheme: an internal expansion cold processing technology of a pipe equal-diameter tee joint comprises the following steps:
the method comprises the following steps: blanking, calculating the blanking specification of a pipe blank according to the forming size of a three-way pipe fitting to be produced, selecting the pipe blank, selecting a mould, cleaning the surface of the pipe blank in advance, keeping the surface dry, fixing the pipe blank in a three-way water expansion forming machine, fixing the mould, cleaning the surrounding environment in advance, and keeping the integral cleanness.
Step two: the expansion type is characterized in that a three-way water expansion forming machine is adopted, a switch of cooling water of a cooler needs to be switched on before the three-way water expansion forming machine is used, two horizontal plungers of the three-way water expansion forming machine move forwards to punch liquid in a die, two side cylinders of the three-way water expansion forming machine continuously move forwards synchronously to extrude a pipe blank, a supercharger inputs ultrahigh-pressure liquid into the die, the volume of the pipe blank is reduced after the pipe blank is extruded, the pressure of the liquid in the pipe blank is increased along with the reduction of the volume of the pipe blank, and when the required pressure of the expansion of a three-way branch pipe is reached, the pipe blank flows along the inner cavity of the die under the dual action of the ultrahigh-pressure liquid in the side cylinders and the die to expand the branch pipe.
Step three: cutting, namely, performing equidistant cutting on the preliminarily formed product to ensure that the product is an equal-diameter tee joint, cutting off parts with abnormal bulges on the surface, simultaneously, detecting the quality, removing the product with cracks and abnormal depressions on the surface to avoid influencing the quality of the whole batch,
step four: cleaning, namely putting the formed product into an ultrasonic cleaning pool for cleaning, controlling the ultrasonic frequency to be 20-30KHZ, simultaneously cleaning the surface and the inside of the product by adopting a soft brush at a working temperature of 50-70 ℃ to avoid the occurrence of stain adhesion, and then drying the product.
Step five: the polishing machine comprises a clamping assembly, a polishing mechanism, a clamp, a grinding and polishing machine and a control clamp, wherein the clamping assembly is used for clamping a product, the clamping assembly is used for clamping the product, the surface of the clamp is required to be smooth, air leakage is avoided, the clamp is prevented from scratching a three-way pipe, the grinding and polishing machine is used for grinding and polishing the three-way pipe, the corners of the product which are relatively sharp are required to be treated, the smoothness of the corners of the product is required to be ensured, after the grinding and polishing are finished, the product is required to be subjected to secondary cleaning treatment, and the surface of the product is coated with anticorrosive paint.
Preferably, if materials of proper types do not exist in the material selection process in the blanking process, a laser cutting knife is needed to cut the pipe blank.
Preferably, the hydraulic machine automatically releases pressure when the pressure of the three-way water expansion forming machine used in the expansion type is over-pressure in a certain time in the forming process, the pressure release time of the three-way water expansion forming machine in the expansion type is consistent with the product forming time, and the liquid adopted by the three-way water expansion forming machine is white emulsified water which is easy to flow and fast in heat dissipation.
Preferably, the cutting of product adopts laser cutting knife in order to guarantee the accurate degree of cutting.
Preferably, the grinding can also be carried out by using a shot blasting machine, and the shot blasting machine used for grinding needs to reduce the diameter of the steel shot and adopts the steel shot with the diameter kept between 0.2 and 0.5 cm.
Preferably, after the polishing is finished, sampling detection is required, the detection content of the sampling detection after the polishing is generally drawing test, flattening test, air pressure test, pressure resistance test, tensile strength and corrosion resistance, the drawing force of socket argon arc welding pipe fitting of a product required by the drawing test is 3 times of the national standard, the pipe fitting is required to be flattened to 1/3 of the outer diameter in the flattening test, but no crack or crack occurs, the air pressure test needs to ensure that the pipe fitting can normally pass through the 1.6Mpa air pressure test without damage, the pressure resistance test needs to ensure that the joint is not leaked under the conditions of 2.5Mpa and 5min of pressure maintaining after the pipe fitting is connected, the tensile strength needs to ensure that the elongation is not less than 35% of the pipe fitting of the product by not less than 520Mpa tensile force, and the corrosion resistance needs to ensure that the welding line of the product is not rusted after the salt spray test.
Compared with the prior art, the invention has the following beneficial effects:
the water-swelling forming machine is favorable for providing sufficient pressure intensity, and is favorable for improving the plasticity of metal to a certain extent, the liquid adopts white emulsified water which is easy to flow and can dissipate heat quickly, and is favorable for improving the transmission efficiency of a medium, meanwhile, the water-swelling forming machine can play a certain protection role by hydraulic pressure opportunity automatic pressure relief within a certain time when the pressure overpressure occurs in the forming process, and avoids the situation that the pressure is too large and only remains one time to damage, and is favorable for better protecting the equipment to a certain extent.
Drawings
FIG. 1 is a production flow chart of the present invention.
Detailed Description
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: an internal expansion cold processing technology of a pipe fitting constant diameter tee joint comprises the following steps:
the method comprises the following steps: blanking, namely calculating the blanking specification of a pipe blank according to the forming size of a three-way pipe fitting to be produced to select the pipe blank, wherein the surface of the pipe blank needs to be cleaned in advance and kept dry when a mould is selected, and the periphery of the pipe blank needs to be cleaned in advance when the mould is fixed in a three-way water-swelling forming machine to keep the integral cleanness when the mould is fixed.
Step two: the expansion type is characterized in that a three-way water expansion forming machine is adopted, a switch of cooling water of a cooler needs to be switched on before the three-way water expansion forming machine is used, two horizontal plungers of the three-way water expansion forming machine move forwards to punch liquid in a die, two side cylinders of the three-way water expansion forming machine continuously move forwards synchronously to extrude a pipe blank, a supercharger inputs ultrahigh-pressure liquid into the die, the volume of the pipe blank is reduced after the pipe blank is extruded, the pressure of the liquid in the pipe blank is increased along with the reduction of the volume of the pipe blank, and when the required pressure of the expansion of a three-way branch pipe is reached, the pipe blank flows along the inner cavity of the die under the dual action of the ultrahigh-pressure liquid in the side cylinders and the die to expand the branch pipe.
Step three: cutting, namely, performing equidistant cutting on the preliminarily formed product to ensure that the product is an equal-diameter tee joint, cutting off parts with abnormal bulges on the surface, simultaneously, detecting the quality, removing the product with cracks and abnormal depressions on the surface to avoid influencing the quality of the whole batch,
step four: and (2) cleaning, namely putting the formed product into an ultrasonic cleaning tank for cleaning, controlling the ultrasonic frequency to be between 20 and 30KHZ, and simultaneously cleaning at the working temperature of between 50 and 70 ℃ while cleaning the surface and the inside of the product by adopting a soft brush to avoid the occurrence of stain adhesion and drying the product.
Step five: the polishing machine comprises a clamping assembly, a polishing mechanism, a clamp, a grinding and polishing machine and a control clamp, wherein the clamping assembly is used for clamping a product, the clamping assembly is used for clamping the product, the surface of the clamp is required to be smooth, air leakage is avoided, the clamp is prevented from scratching a three-way pipe, the grinding and polishing machine is used for grinding and polishing the three-way pipe, the corners of the product which are relatively sharp are required to be treated, the smoothness of the corners of the product is required to be ensured, after the grinding and polishing are finished, the product is required to be subjected to secondary cleaning treatment, and the surface of the product is coated with anticorrosive paint.
The invention provides a technical scheme that: an internal expansion cold processing technology for a pipe fitting equal-diameter tee joint is disclosed, wherein if materials with proper types do not exist in the blanking process, a laser cutting knife is needed to cut a pipe blank; the internal expansion cold processing technology of the equal-diameter tee joint of the pipe fitting is characterized in that a tee joint water swelling forming machine adopted in a swelling type can automatically release pressure within a certain time when the pressure overpressure occurs in the forming process, the pressure release time of the tee joint water swelling forming machine in the swelling type is consistent with the product forming time, liquid adopted by the tee joint water swelling forming machine is white emulsified water with easy flowability and quick heat dissipation, the plasticity of metal can be improved to a certain extent, the white emulsified water with the easy flowability and quick heat dissipation is adopted as the liquid, the transmission efficiency of a medium can be improved, meanwhile, the hydraulic machine can automatically release pressure within a certain time when the pressure overpressure occurs in the forming process of the water swelling forming machine, a certain protection effect can be achieved, the situation that the damage is caused when the pressure is too large is avoided, and a certain protection effect on equipment can be achieved better.
The invention provides a technical scheme that: an internal expansion cold working process of a pipe equal-diameter tee joint is disclosed, wherein a laser cutting knife is adopted for cutting a product to ensure the cutting accuracy; the grinding can also be processed by adopting a shot blasting machine, the diameter of a steel shot which is adopted by the grinding can be reduced by adopting the steel shot with the diameter kept at 0.2-0.5cm, laser cutting equipment is adopted for cutting products or pipe blanks, the efficiency of cutting is favorably improved, the quality of cutting is improved, the precision of cutting is further improved, the flexibility of cutting is favorably improved, the adaptation degree of cutting is improved, the occurrence of burrs at the edges of the products is reduced, the smoothness of the cut edges is favorably improved, meanwhile, the adoption of the shot blasting machine can also serve as a spare option of a user, the shot blasting machine is adopted as polishing and grinding equipment, the compression resistance of the products is favorably improved, the overall smoothness is lower than that of the grinding equipment, meanwhile, the laser cutting equipment is adopted for cutting the products or the pipe blanks, the efficiency of cutting is favorably improved, the quality of cutting is improved, the precision of cutting is further improved, the flexibility of cutting is favorably improved, the adaptation degree of cutting is improved, the appearance of burrs at the edges of the products is reduced, the smoothness of the cutting edges is favorably improved, the dust cleaning efficiency of the ultrasonic cleaning equipment is favorably improved, the dirt cleaning effect of the ultrasonic cleaning equipment is favorably, and the dirt cleaning efficiency of the ultrasonic cleaning equipment is improved.
The invention provides a technical scheme that: an internal expansion cold machining process for a pipe equal-diameter tee joint is characterized in that sampling detection is needed after grinding is finished, the detection content of the sampling detection after grinding is generally drawing test, flattening test, air pressure test, tensile strength and corrosion resistance, the drawing force of socket argon arc welding pipe connection of a product needed by the drawing test is 3 times of the national standard, the pipe needs to be flattened to 1/3 of the outer diameter in the flattening test, cracks or splits do not occur, the air pressure test needs to ensure that the pipe can normally pass the 1.6Mpa air pressure test without being damaged, the pressure test needs to ensure that the connection part of the pipe and the pipe does not leak under the conditions of 2.5MPa and 5min pressure maintaining after the pipe and the pipe are connected, the tensile strength needs to carry out not less than 520Mpa tensile force on the pipe of the product to ensure that the elongation of the pipe is not less than 35%, the corrosion resistance needs to ensure that the welding line of the product is not rusted after the salt spray test, high-requirement detection on the product is beneficial to improving the quality of the product, the use experience of a user is improved, and the threshold of the quality of finished products is favorably changed.
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 various 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. An internal expansion cold working process of a pipe fitting constant diameter tee joint is characterized by comprising the following steps:
the method comprises the following steps: blanking, namely calculating the blanking specification of a pipe blank according to the forming size of a three-way pipe fitting to be produced to select the pipe blank, wherein the surface of the pipe blank needs to be cleaned in advance and kept dry when a mould is selected, and the periphery of the pipe blank needs to be cleaned in advance when the mould is fixed in a three-way water expansion forming machine to keep the integral cleaning degree when the mould is fixed;
step two: expanding, namely adopting a three-way water-swelling forming machine, opening a switch of cooling water of a cooler before the three-way water-swelling forming machine is used, moving forwards through two horizontal plungers of the three-way water-swelling forming machine to punch liquid into a die, continuously and synchronously moving forwards through two side cylinders of the three-way water-swelling forming machine, extruding a pipe blank, inputting ultrahigh-pressure liquid into the die by a supercharger, reducing the volume of the pipe blank after extrusion, increasing the pressure of the liquid in the pipe blank along with the reduction of the volume of the pipe blank, and expanding the branch pipe by flowing along an inner cavity of the die under the double action of the ultrahigh-pressure liquid in the side cylinders and the die when the required pressure for expanding the three-way branch pipe is reached;
step three: cutting, namely, performing equidistant cutting on the preliminarily formed product to ensure that the product is an equal-diameter tee joint, cutting off parts with abnormal bulges on the surface, simultaneously, detecting the quality, removing the product with cracks and abnormal depressions on the surface to avoid influencing the quality of the whole batch,
step four: cleaning, namely putting the formed product into an ultrasonic cleaning pool for cleaning, controlling the ultrasonic frequency to be 20-30KHZ, simultaneously cleaning the surface and the interior of the product by adopting a soft brush at a working temperature of 50-70 ℃ to avoid the occurrence of stain adhesion, and drying the product;
step five: the polishing machine comprises a clamping assembly, a polishing mechanism, a clamp, a grinding and polishing machine and a control clamp, wherein the clamping assembly is used for clamping a product, the clamping assembly is used for clamping the product, the surface of the clamp is required to be smooth, air leakage is avoided, the clamp is prevented from scratching a three-way pipe, the grinding and polishing machine is used for grinding and polishing the three-way pipe, the corners of the product which are relatively sharp are required to be treated, the smoothness of the corners of the product is required to be ensured, after the grinding and polishing are finished, the product is required to be subjected to secondary cleaning treatment, and the surface of the product is coated with anticorrosive paint.
2. The internal expansion cold working process of the pipe fitting constant diameter tee joint as claimed in claim 1, wherein: if materials with proper types do not exist in the blanking process, a laser cutting knife needs to be adopted to cut the pipe blank.
3. The internal expansion cold working process of the pipe fitting constant diameter tee joint as claimed in claim 1, wherein the internal expansion cold working process comprises the following steps: the three-way water expansion forming machine adopted in the expansion type can automatically release pressure within a certain time when the pressure is over-pressure in the forming process, the pressure release time of the three-way water expansion forming machine in the expansion type is consistent with the product forming time, and the liquid adopted by the three-way water expansion forming machine is white emulsified water which is easy to flow and fast in heat dissipation.
4. The internal expansion cold working process of the pipe fitting constant diameter tee joint as claimed in claim 1, wherein: the cutting of product adopts laser cutting knife in order to guarantee the accurate degree of cutting.
5. The internal expansion cold working process of the pipe fitting constant diameter tee joint as claimed in claim 1, wherein: the grinding can also be carried out by adopting a shot blasting machine, and the shot blasting machine adopted by the grinding needs to reduce the diameter of the steel shot and adopts the steel shot with the diameter kept between 0.2 and 0.5 cm.
6. The internal expansion cold working process of the pipe fitting constant diameter tee joint as claimed in claim 1, wherein: the method is characterized in that sampling detection is needed after polishing is completed, the detection content of the sampling detection after polishing generally comprises a drawing test, a flattening test, an air pressure test, a pressure resistance test, tensile strength and corrosion resistance, the drawing test needs that the socket argon arc welding pipe fitting of a product is connected with the drawing force which is 3 times of the national standard, the flattening test needs that the pipe fitting is flattened to 1/3 of the outer diameter without cracks or splits, the air pressure test needs to ensure that the pipe fitting can normally pass the 1.6Mpa air pressure test without damage, the pressure resistance test needs that the joint of the pipe fitting and the pipe fitting is not leaked under the conditions of 2.5Mpa and 5min of pressure maintaining, the tensile strength needs to carry out not less than 520Mpa tensile force on the pipe fitting of the product to ensure that the elongation is not less than 35%, and the corrosion resistance needs to ensure that the welding line of the product is not rusted after the salt spray test.
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| CN202211608547.0A CN115870704A (en) | 2022-12-14 | 2022-12-14 | Internal expansion cold machining process for equal-diameter tee joint of pipe fitting |
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| CN202211608547.0A CN115870704A (en) | 2022-12-14 | 2022-12-14 | Internal expansion cold machining process for equal-diameter tee joint of pipe fitting |
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Citations (7)
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| JPH10137863A (en) * | 1996-11-07 | 1998-05-26 | Sumitomo Metal Ind Ltd | Surface treated steel tube for hydraulic bulge working |
| CN102240690A (en) * | 2011-04-21 | 2011-11-16 | 湖州机床厂有限公司 | Three-way pipe extrusion molding device and extrusion molding technology thereof |
| CN206601716U (en) * | 2017-01-05 | 2017-10-31 | 东莞市海亿机械设备有限公司 | A kind of smart mobile phone fingerprint ring |
| CN108838270A (en) * | 2018-08-27 | 2018-11-20 | 广东思豪内高压科技有限公司 | A kind of water swelling moulding process of universal joint for automobile |
| CN110523802A (en) * | 2019-08-15 | 2019-12-03 | 宁波金田铜管有限公司 | A kind of processing technology of T-branch used in pipe-lines part |
| CN112917107A (en) * | 2021-02-26 | 2021-06-08 | 卡狮管业(上海)有限公司 | Production process of constant-diameter tee joint of stainless steel clamping and pressing type pipe fitting |
| CN217889202U (en) * | 2022-08-24 | 2022-11-25 | 江苏志得管业有限公司 | Pipeline bulging machine convenient to get material |
-
2022
- 2022-12-14 CN CN202211608547.0A patent/CN115870704A/en active Pending
Patent Citations (7)
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|---|---|---|---|---|
| JPH10137863A (en) * | 1996-11-07 | 1998-05-26 | Sumitomo Metal Ind Ltd | Surface treated steel tube for hydraulic bulge working |
| CN102240690A (en) * | 2011-04-21 | 2011-11-16 | 湖州机床厂有限公司 | Three-way pipe extrusion molding device and extrusion molding technology thereof |
| CN206601716U (en) * | 2017-01-05 | 2017-10-31 | 东莞市海亿机械设备有限公司 | A kind of smart mobile phone fingerprint ring |
| CN108838270A (en) * | 2018-08-27 | 2018-11-20 | 广东思豪内高压科技有限公司 | A kind of water swelling moulding process of universal joint for automobile |
| CN110523802A (en) * | 2019-08-15 | 2019-12-03 | 宁波金田铜管有限公司 | A kind of processing technology of T-branch used in pipe-lines part |
| CN112917107A (en) * | 2021-02-26 | 2021-06-08 | 卡狮管业(上海)有限公司 | Production process of constant-diameter tee joint of stainless steel clamping and pressing type pipe fitting |
| CN217889202U (en) * | 2022-08-24 | 2022-11-25 | 江苏志得管业有限公司 | Pipeline bulging machine convenient to get material |
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