Processing method of polytetrafluoroethylene (PTFE) lining and steel-fluorine integrated PTFE lining tower

Abstract

The invention discloses a processing method of a polytetrafluoroethylene (PTFE)-lined steel-fluorine integrated PTFE-lined tower, which comprises the following steps of: S1, processing a carbon steel shell: confirming a processing drawing, processing and manufacturing according to a container category to which a container belongs, and polishing the inner wall of the steel shell according to the requirement of the lined container until the inner wall reaches the required grade of the lining; s2, bonding preparation is conducted, specifically, after polishing miscellaneous slag on the inner wall of the steel shell is cleaned, the inner surface of the steel shell is coated with an imported high-temperature binder; s3, PTFE lining preparation: preparing a fluorine material bar, turning the fluorine material bar into a thin strip, winding the thin strip on a mold, sintering the wound fluorine material in a furnace, and naturally cooling for a period of time to obtain a lining primary material; the invention effectively solves the problem that the equipment is easily damaged in a negative pressure environment, expands the application range of the PTFE lining container, especially the negative pressure resistance, prolongs the service life of the container, and can greatly prolong the service life of the PTFE lining equipment and pipeline by the winding process.

Description

Technical Field

[0001] The invention relates to the technical field of PTFE lined pipes, and in particular to a method for processing a tetrafluoroethylene lined steel-fluorine integrated PTFE lined tower. Background Art

[0002] Tetrafluoroethylene is a polymer of tetrafluoroethylene, abbreviated as PTFE. PTFE lining is a lining material made of polytetrafluorodiene. It is a durable and reliable material used in various fields such as the transportation of corrosive fluid media and industrial pure water, chemical pure water, ionized water, and deionized water. Fluorine material has stable chemical properties and is resistant to high temperatures, wear, aging, and strong corrosion. It is widely used in chemical production reactors, towers, and pipes, valves, pumps, and other equipment for conveying media.

[0003] However, due to the large thermal expansion coefficient of the fluorine material itself, its lining will produce large deformation due to temperature changes during use. It is difficult to achieve complete fit between the fluorine material and the metal components in general production processes. The lining layer often deforms and collapses, and the flange micro-fractures and other phenomena will cause the equipment to be unable to continue to be used. Therefore, it is urgent to design a processing method for a PTFE-lined steel-fluorine integrated PTFE-lined tower to solve the above problems. Summary of the Invention

[0004] The purpose of the present invention is to provide a method for processing a PTFE-lined steel-fluorine integrated PTFE-lined tower to solve the above-mentioned shortcomings in the prior art.

[0005] In order to achieve the above object, the present invention provides the following technical solutions: A method for processing a PTFE-lined steel-fluorine integrated PTFE-lined tower comprises the following steps: S1. Carbon Steel Shell Processing: Confirm the processing drawings, process and manufacture the container according to the container category, and polish the inner wall of the steel shell to the required grade of the lining according to the needs of the lining container; S2. Bonding preparation: After cleaning the polishing residue on the inner wall of the steel shell, apply imported high-temperature adhesive to the inner surface of the steel shell; S3. PTFE lining preparation: prepare fluorine material rods, fluorine material rods after turning thin strips wound on the mold, and then the wound fluorine material into the furnace sintering, and naturally cool for a period of time to obtain the lining initial material; S4. Lining demoulding: The cooled lining material is expanded outward from the mold to a certain size to separate the lining material from the mold; S5. Surface modification: Clean the detached lining material to remove dirt on the lining material, and then evenly coat the surface of the lining material with a fluoride adhesive; S6. Evacuation and pressurization treatment: Under heating conditions, the air in the gap between the lining material and the steel shell is evacuated and pressurized; S7. Testing: After the lining material is heated, plasticized, and set, a water pressure test is performed on the interior of the lining material. Using an electric spark detector, the surface of the lining material is inspected for cracks, defects, and fatigue. S8. Bonding and sealing: The PTFE lining material is tightly bonded to the steel shell for sealing assembly, and the PTFE lining effectively matches the shape of the metal shell.

[0006] Preferably, in said S1, when the inner wall of the steel shell is polished, the rotation speed of the polishing wheel is 120 r / min, and in said S2, the high-temperature adhesive is coated on the inner surface of the steel shell to a thickness of 3 mm to 15 mm.

[0007] Preferably, in said S3, the turning and cutting feed speed of the fluorine material rod is 25-60 m / min, and in said S3, the temperature of sintering the wound fluorine material into the furnace is 330-380° C., and then naturally cooled for 100 minutes.

[0008] Preferably, in S4, the lining raw material is expanded outward from the mold, and the expansion distance between the lining raw material and the mold is 3 cm-18 cm.

[0009] Preferably, in S4, the peeling strength of the lining material from the mold is 30-80 N / cm.

[0010] Preferably, in said S5, the cleaning pressure value of the detached lining material is 1.6-5 MPa, and the thickness of the fluoride adhesive coated on the surface of the lining material is 5 mm-18 mm.

[0011] Preferably, in S6, the heating temperature is 20°C-180°C, and the pressure value of the air in the gap between the lining material and the steel shell during evacuation and pressurization is -0.03MPa-1.6MPa.

[0012] Preferably, in said S7, the temperature of heating, plasticizing and setting the lining material is 260-310°C, and water pressure is applied inside the lining material, and the pressure value of the water pressure test is 1MPa-3.6MPa.

[0013] Preferably, in said S7, the voltage range when using the electric spark detection instrument is 3-30 kV, and the electric spark detection instrument will alarm after detecting the occurrence of cracks, bubbles, and holes.

[0014] Preferably, in said S8, the high temperature adhesive of the steel shell is bonded with the fluoride adhesive, and the PTFE lining material is tightly fitted to the steel shell.

[0015] In the above technical scheme, the present invention provides a processing method for a PTFE-lined steel-fluorine integrated PTFE-lined tower. The present invention effectively solves the problem that the equipment is easily damaged in a negative pressure environment, expands the application range of the PTFE-lined container, especially the negative pressure resistance, and extends the service life of the container. The winding process can greatly extend the service life of PTFE-lined equipment and pipelines; the molding technology of the present invention adopts winding and outer surface chemical modification PTFE lining technology and uniform coating of fluoride adhesive technology, changing the "loose lining" to "bonded tight lining" to form a PTFE lining, overcoming defects such as lining deformation, delamination, and wrinkling caused by thermal expansion and contraction; the present invention also adopts heating and cooling, inflation and pressurization, and high-temperature plasticizing technology to increase the density of the PTFE lining layer, eliminate the stress of the PTFE lining, stabilize the PTFE performance, overcome thermal deformation and cold flow defects, and achieve effective matching of the PTFE lining with the metal shell shape. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments described in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0017] Figure 1 The present invention provides a schematic flow chart of a method for processing a PTFE-lined steel-fluorine integrated PTFE-lined tower.

[0018] Figure 2 A schematic diagram of a processing method provided for an embodiment of a processing method of a tetrafluoroethylene-lined steel-fluorine integrated PTFE lined tower of the present invention. DETAILED DESCRIPTION

[0019] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings. Example

[0020] like Figure 1-2 As shown, the embodiment of the present invention provides a method for processing a PTFE lined steel-fluorine integrated PTFE lined tower, comprising the following steps: S1. Carbon Steel Shell Processing: Confirm the processing drawings, process and manufacture the container according to the container category, and polish the inner wall of the steel shell according to the requirements of the lining container. When polishing the inner wall of the steel shell, the polishing wheel speed used is 120r / min until the required grade of the lining is achieved; S2. Bonding Preparation: After cleaning the polishing residue on the inner wall of the steel shell, apply imported high-temperature adhesive to the inner surface of the steel shell. The high-temperature adhesive is applied to the inner surface of the steel shell with a thickness of 5mm; S3. PTFE Lining Preparation: Fluorine material rods are prepared, cut into thin strips, and then wound around a mold at a feed rate of 40 m / min. The wound fluorocarbon material is then sintered in a furnace at 350°C and naturally cooled for 100 minutes. S4. Lining demolding: The cooled lining material is expanded outward from the mold to a certain size. The distance between the lining material and the mold is expanded to 10 cm, so that the lining material is separated from the mold. The peeling strength of the lining material from the mold is 35N / cm. S5. Surface modification: The detached lining material is cleaned to remove dirt from the lining material, and then a fluoride adhesive is evenly applied to the surface of the lining material. The detached lining material cleaning pressure is 4 MPa, and the fluoride adhesive is applied to the lining material surface to a thickness of 7 mm. S6. Evacuation and pressurization treatment: Under heating conditions, the temperature is 100°C, and the air in the gap between the lining material and the steel shell is evacuated and pressurized. The pressure value of the air in the gap between the lining material and the steel shell is 0.7MPa; S7. Testing: After the lining material has been heated, plasticized, and set at a temperature of 280°C, a hydraulic pressure test is performed on the interior of the lining material at a pressure of 1.6 MPa. Using a spark detector with a voltage range of 15 kV, the surface of the lining material is inspected for cracks, defects, and fatigue. The spark detector will sound an alarm if cracks, bubbles, or holes are detected. S8. Bonding and sealing: The PTFE lining material is tightly bonded to the steel shell, and the high-temperature adhesive of the steel shell and the fluoride adhesive are bonded together for sealing assembly, so that the PTFE lining effectively matches the shape of the metal shell. Example

[0021] A method for processing a PTFE-lined steel-fluorine integrated PTFE-lined tower comprises the following steps: S1. Carbon Steel Shell Processing: Confirm the processing drawings, process and manufacture the container according to the container category, and polish the inner wall of the steel shell according to the requirements of the lining container. When polishing the inner wall of the steel shell, the polishing wheel speed used is 120r / min until the required grade of the lining is achieved; S2. Bonding Preparation: After cleaning the polishing residue on the inner wall of the steel shell, apply imported high-temperature adhesive to the inner surface of the steel shell. The high-temperature adhesive is applied to the inner surface of the steel shell with a thickness of 7mm. S3. PTFE Lining Preparation: Fluorine material rods are prepared, cut into thin strips, and then wound onto a mold at a feed rate of 30 m / min. The wound fluorocarbon material is then sintered in a furnace at 350°C and naturally cooled for 100 minutes. S4. Lining demolding: The cooled lining material is expanded outward from the mold to a certain size. The distance between the lining material and the mold is expanded to 8 cm. The lining material is separated from the mold. The peeling strength of the lining material from the mold is 45 N / cm. S5. Surface modification: The detached lining material is cleaned to remove dirt from the lining material, and then a fluoride adhesive is evenly coated on the surface of the lining material. The detached lining material cleaning pressure is 3.5 MPa, and the fluoride adhesive is coated on the lining material surface to a thickness of 8 mm. S6. Evacuation and pressurization treatment: Under heating conditions, the temperature is 120°C, and the air in the gap between the lining material and the steel shell is evacuated and pressurized. The pressure value of the air in the gap between the lining material and the steel shell is 1.2MPa; S7. Testing: After the lining material has been heated, plasticized, and set at a temperature of 290°C, a hydraulic pressure test is performed on the interior of the lining material at a pressure of 2.6 MPa. Using a spark detector with a voltage range of 19 kV, the surface of the lining material is inspected for cracks, defects, and fatigue. The spark detector will sound an alarm if cracks, bubbles, or holes are detected. S8. Bonding and sealing: The PTFE lining material is tightly bonded to the steel shell, and the high-temperature adhesive of the steel shell and the fluoride adhesive are bonded together for sealing assembly. The PTFE lining effectively matches the shape of the metal shell. Example

[0022] A method for processing a PTFE-lined steel-fluorine integrated PTFE-lined tower comprises the following steps: S1. Carbon Steel Shell Processing: Confirm the processing drawings, process and manufacture the container according to the container category, and polish the inner wall of the steel shell according to the requirements of the lining container. When polishing the inner wall of the steel shell, the polishing wheel speed used is 120r / min until the required grade of the lining is achieved; S2. Bonding Preparation: After cleaning the polishing residue on the inner wall of the steel shell, apply imported high-temperature adhesive to the inner surface of the steel shell. The high-temperature adhesive is applied to the inner surface of the steel shell with a thickness of 12mm. S3. PTFE Lining Preparation: Fluorine material rods are prepared, cut into thin strips, and then wound onto a mold at a feed rate of 50 m / min. The wound fluorocarbon material is then sintered in a furnace at 370°C and naturally cooled for 100 minutes. S4. Lining demolding: The cooled lining material is expanded outward from the mold to a certain size. The expansion distance between the lining material and the mold is 12 cm. The lining material is separated from the mold. The peeling strength of the lining material from the mold is 55 N / cm. S5. Surface modification: The detached lining material is cleaned to remove dirt from the lining material, and then a fluoride adhesive is evenly applied to the surface of the lining material. The detached lining material cleaning pressure is 4 MPa, and the fluoride adhesive is applied to a thickness of 13 mm on the surface of the lining material. S6. Evacuation and pressurization treatment: Under heating conditions, the temperature is 90°C, and the air in the gap between the lining material and the steel shell is evacuated and pressurized. The pressure value of the air in the gap between the lining material and the steel shell is 1MPa; S7. Testing: After the lining material has been heated, plasticized, and set at a temperature of 260°C, a hydraulic pressure test is performed on the interior of the lining material at a pressure of 1.8 MPa. Using a spark detector with a voltage range of 17 kV, the surface of the lining material is inspected for cracks, defects, and fatigue. The spark detector will sound an alarm if cracks, bubbles, or holes are detected. S8. Bonding and sealing: The PTFE lining material is tightly bonded to the steel shell, and the high-temperature adhesive of the steel shell and the fluoride adhesive are bonded together for sealing assembly. The PTFE lining effectively matches the shape of the metal shell.

[0023] Working principle: The turning feed speed, sintering temperature, pressure value and peeling strength of the processing methods used in Example 1, Example 2 and Example 3 are different, and the other parameters are consistent. By conducting experimental comparison on the final obtained PTFE lined steel-fluorine integrated PTFE lined pipe, the above three groups of examples are obtained through experiments and preparation. The effect of Example 2 is the best. According to the needs of the lined container, Example 2 polishes the inner wall of the steel shell until it reaches the required grade of the lining. After the polishing residue on the inner wall of the steel shell is cleaned, a high-temperature adhesive is applied to the inner surface of the steel shell. The fluorine material rod is then turned into a thin strip and wound onto the mold, which is then put into the furnace for sintering. The lining material is then expanded outward from the mold to be demoulded. The detached lining material is cleaned and then evenly coated with fluoride adhesive on the lining material. The operator evacuates and pressurizes the air in the gap between the lining material and the steel shell. The lining material is then heated, plasticized, and shaped, and subjected to a water pressure test. The electric spark detection instrument then detects cracks, defects, and fatigue on the surface of the lining material. An alarm can be issued if an abnormality is detected, and finally the PTFE lining material is tightly bonded to the steel shell.

[0024] The above description is merely illustrative of certain exemplary embodiments of the present invention. It goes without saying that those skilled in the art will be able to modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of protection of the claims.

Claims

1. A method for processing a PTFE-lined steel-fluorine integrated PTFE-lined tower, characterized in that: The following steps are involved: S1. Carbon Steel Shell Processing: Confirm the processing drawings, process and manufacture the container according to the container category, and polish the inner wall of the steel shell to the required grade of the lining according to the needs of the lining container; S2. Bonding preparation: After cleaning the polishing residue on the inner wall of the steel shell, apply imported high-temperature adhesive to the inner surface of the steel shell; S3. PTFE lining preparation: prepare fluorine material rods, fluorine material rods after turning thin strips wound on the mold, and then the wound fluorine material into the furnace sintering, and naturally cool for a period of time to obtain the lining initial material; S4. Lining demoulding: The cooled lining material is expanded outward from the mold to a certain size to separate the lining material from the mold; S5. Surface modification: Clean the detached lining material to remove dirt on the lining material, and then evenly coat the surface of the lining material with a fluoride adhesive; S6. Evacuation and pressurization treatment: Under heating conditions, the air in the gap between the lining material and the steel shell is evacuated and pressurized; S7. Testing: After the lining material is heated, plasticized, and set, a water pressure test is performed on the interior of the lining material. Using an electric spark detector, the surface of the lining material is inspected for cracks, defects, and fatigue. S8. Bonding and sealing: The PTFE lining material is tightly bonded to the steel shell for sealing assembly, and the PTFE lining effectively matches the shape of the metal shell.

2. The processing method of a tetrafluoroethylene lined steel-fluorine integrated PTFE lined tower according to claim 1, characterized in that: In said S1, when the inner wall of the steel shell is polished, the rotation speed of the polishing wheel is 120r / min. In said S2, the high-temperature adhesive is coated on the inner surface of the steel shell with a thickness of 3mm-15mm.

3. The processing method of a tetrafluoroethylene lined steel-fluorine integrated PTFE lined tower according to claim 1, characterized in that: In said S3, the turning and cutting feed speed of the fluorine material rod is 25-60 m / min. In said S3, the temperature of sintering the wound fluorine material into the furnace is 330-380° C., and then naturally cooled for 100 minutes.

4. The processing method of a tetrafluoroethylene lined steel-fluorine integrated PTFE lined tower according to claim 1, characterized in that: In the above-mentioned S4, the lining raw material is expanded outward from the mold, and the expansion distance between the lining raw material and the mold is 3 cm to 18 cm.

5. The processing method of a tetrafluoroethylene lined steel-fluorine integrated PTFE lined tower according to claim 1, characterized in that: In the above-mentioned S4, the peeling strength of the lining raw material from the mold is 30-80N / cm.

6. The processing method of a tetrafluoroethylene lined steel-fluorine integrated PTFE lined tower according to claim 1, characterized in that: In the above-mentioned S5, the cleaning pressure value of the separated lining material is 1.6-5 MPa, and the thickness of the fluoride adhesive coated on the surface of the lining material is 5 mm-18 mm.

7. The processing method of a tetrafluoroethylene lined steel-fluorine integrated PTFE lined tower according to claim 1, characterized in that: In the above-mentioned S6, the heating temperature is 20° C.-180° C., and the pressure of the air in the gap between the lining material and the steel shell is evacuated and pressurized to a value of -0.03 MPa-1.6 MPa.

8. The method for processing a tetrafluoroethylene-lined steel-fluorine integrated PTFE lined tower according to claim 1, characterized in that: In the above-mentioned S7, the temperature of heating, plasticizing and setting the lining material is 260-310° C., and water pressure is applied to the interior of the lining material. The pressure value of the water pressure test is 1 MPa-3.6 MPa.

9. The method for processing a tetrafluoroethylene-lined steel-fluorine integrated PTFE lined tower according to claim 1, characterized in that: In the above S7, the voltage range when using the electric spark detection instrument is 3-30kV, and the electric spark detection instrument will alarm after detecting cracks, bubbles, and holes.

10. The method for processing a PTFE lined steel-fluorine integrated PTFE lined tower according to claim 1, characterized in that: In the above-mentioned S8, the high-temperature adhesive of the steel shell is bonded with the fluoride adhesive, and the PTFE lining material is tightly fitted to the steel shell.

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