阅读说明：本技术 一种钢衬聚四氟乙烯管道制作工艺 (Manufacturing process of steel lining polytetrafluoroethylene pipeline ) 是由 施正良 于 2020-03-31 设计创作，主要内容包括：本发明公开了一种钢衬聚四氟乙烯管道制作工艺,包括以下步骤：A、钢管与法兰装配；B、采用表面抛丸喷铁砂后酸洗,密封两端法兰；C、通过0.8MPa气压测试是否漏气；D、聚四氟乙烯管推压管,将管体一端固定,另一端用钢丝绳固定在牵引装置上面,牵引装置匀速拉伸,将聚四氟乙烯管拉伸10%~12%后暂停；E、将拉伸后的聚四氟乙烯管表面用细砂纸打磨,丙酮洗涤后晾干,再用钠-萘络合物进行表面处理；F、将钢管套在拉升的聚四氟乙烯管上面,聚四氟乙烯管收紧衬在钢管内,将衬好的管道放入烘箱进行50~55摄氏度下的应力处理,最后翻遍成型。本发明工艺简单,聚四氟乙烯与钢管之间无间隙,能建立真空状态,可以在180℃以下全真空情况下长期使用。(The invention discloses a manufacturing process of a steel lining polytetrafluoroethylene pipeline, which comprises the following steps: A. assembling the steel pipe and the flange; B. performing surface shot blasting, iron sand spraying and acid washing, and sealing flanges at two ends; C. testing whether air leakage occurs or not by 0.8MPa air pressure; D. the pipe body is pressed by a polytetrafluoroethylene pipe, one end of the pipe body is fixed, the other end of the pipe body is fixed on a traction device through a steel wire rope, the traction device stretches at a constant speed, and the polytetrafluoroethylene pipe is suspended after being stretched by 10% -12%; E. polishing the surface of the stretched polytetrafluoroethylene tube by using fine sand paper, washing by using acetone, then airing, and then performing surface treatment by using a sodium-naphthalene complex; F. sleeving a steel pipe on the stretched polytetrafluoroethylene pipe, tightly tightening the polytetrafluoroethylene pipe to line the steel pipe, putting the lined pipe into an oven to perform stress treatment at 50-55 ℃, and finally turning over for molding. The invention has simple process, no gap between the polytetrafluoroethylene and the steel pipe, can establish a vacuum state, and can be used for a long time under the condition of full vacuum below 180 ℃.)

1. A manufacturing process of a steel lining polytetrafluoroethylene pipeline is characterized by comprising the following steps:

A. assembling a steel pipe and a flange, wherein the flange of the steel pipe is welded in a socket joint mode, and two O-shaped sealing grooves are machined on the sealing surface of the flange to finish welding;

B. performing inner surface treatment, namely performing surface shot blasting, iron sand spraying and acid washing, and sealing flanges at two ends;

C. air pressure test, namely testing whether air leakage exists or not through 0.8MPa air pressure to ensure that no air holes and no leakage points exist at the welded part of the steel pipe and other places integrally;

D. the polytetrafluoroethylene tube is pushed and pressed, one end of the polytetrafluoroethylene tube body is fixed, the other end of the polytetrafluoroethylene tube body is fixed on a traction device through a steel wire rope, the steel wire rope penetrates through the steel tube, the traction device stretches at a constant speed, the polytetrafluoroethylene tube is suspended after being stretched by 10% -12%, and the polytetrafluoroethylene tube is kept in a traction state all the time;

E. surface treatment, namely polishing the surface of the stretched polytetrafluoroethylene tube by using fine sand paper, washing the surface by using acetone, drying the surface by using air, performing surface treatment by using a sodium-naphthalene complex, coating a sodium-naphthalene complex solution on the surface of the polytetrafluoroethylene tube by using a polyethylene brush, uniformly coating the sodium-naphthalene complex solution along one direction, and finally, treating the surface residues of the polytetrafluoroethylene tube by using acetone until the surface is completely dried;

F. and (3) forming, namely sleeving a steel pipe on the lifted polytetrafluoroethylene pipe, loosening the traction device, tightly tightening and lining the polytetrafluoroethylene pipe in the steel pipe, putting the lined pipe into an oven for stress treatment at 50-55 ℃, and finally turning over for forming after the treatment for 3.5-4 hours.

2. The process of claim 1, wherein the steel-lined polytetrafluoroethylene tube is prepared by the following steps: and B, in the step A, the flange opening of the steel pipe adopts R-angle transition, and the flange is a flange with a convex surface on a sealing surface.

3. The process of claim 1, wherein the steel-lined polytetrafluoroethylene tube is prepared by the following steps: and D, carrying out thin-wall high-speed thin-.

4. The process of claim 1, wherein the steel-lined polytetrafluoroethylene tube is prepared by the following steps: and E, coating the sodium-naphthalene complex solution on the surface of the polytetrafluoroethylene tube, wherein the thickness of the solution after brushing is 0.55-0.6 mm.

Technical Field

The invention relates to a manufacturing process of a polytetrafluoroethylene-lined pipeline, in particular to a manufacturing process of a steel-lined polytetrafluoroethylene pipeline,

background

At present, steel polytetrafluoroethylene pipelines in the market are various in types and have different performances. The molded steel lining polytetrafluoroethylene straight pipe is adopted in the market more frequently, and the problems are that the steel lining and the polytetrafluoroethylene are not adhered, and because the polytetrafluoroethylene has non-adhesiveness, a gap exists between the tetrafluoroethylene and the steel pipe, and the pipeline is used under positive pressure and has no problem, but cannot be used under the conditions of high temperature and negative pressure; the common technology of straight pipe steel lining polytetrafluoroethylene is that a pushing pipe is adopted, one end of a polytetrafluoroethylene pipe is arranged on a winch, the polytetrafluoroethylene pipe is pulled and stretched into a steel pipe, and then the polytetrafluoroethylene pipe is turned over for forming, and in the redrawing process of the polytetrafluoroethylene pipe, the resistance is increased, and the stretching force applied to the polytetrafluoroethylene pipe is increased progressively. It is critical that such tensile force is not evenly distributed from the entire tetrafluoro-pipe. The damaged tetrafluoro pipe has an irregular quality problem because the tetrafluoro layer and the steel pipe are tightly lined and are not tightly attached, so that the tetrafluoro layer expands to bubble or contract to break under the change of temperature of the pipeline. And thirdly, at normal temperature, the polytetrafluoroethylene and the steel pipe are tightly lined, and a vacuum state is established, so that the pipeline can resist certain negative pressure, but the negative pressure resistance is gradually weakened along with the rise of the problem. After all, the tetrafluoro is not adhered to the steel pipe, and the tetrafluoro expands and moves when the temperature rises, thereby causing the collapse under the condition of negative pressure.

The invention is a process for manufacturing a fluorine-lined pipeline with the patent number of CN102615861B, and the patent name is an invention patent of a manufacturing process of the fluorine-lined pipeline, the process adopts a steel shell as a pressure-bearing carrier, polytetrafluoroethylene powder is subjected to water injection pressure through the inside of a rubber leather bag and is molded by compression, then the most key technology is that in the baking oven sintering process, sealing surfaces at two ends of a straight pipe are sealed, air is injected inwards, and the polytetrafluoroethylene is attached to the steel pipe by maintaining certain air pressure or adding a substance capable of being gasified for pressurization. This process has two disadvantages, one is that the steel shell cannot withstand the required forming pressure of the tetrafluoro compound, and the required forming pressure of the tetrafluoro compound is 20MPa, so that the density of the tetrafluoro compound is less than 2.16g/cm3 due to the reduction of the tetrafluoro forming pressure, and the transmission pipeline inevitably brings about the risk of infiltration. Secondly, gas injection is carried out under the condition of heating of the oven, so that the safety problem is brought, the yield is greatly reduced, after all, the sintering time of the tetrafluoro pipeline is more than 10 hours, the efficiency is low, and the cost of the product is higher.

Disclosure of Invention

The invention aims to provide a manufacturing process of a fluorine-lined pipeline, which can overcome the defects that the pipeline in the prior art cannot resist high temperature and negative pressure and the defect that solid powder or particles are required to be used as fillers during pipeline processing, and has the advantages that a polytetrafluoroethylene lining is tightly matched with the inner surface of a steel pipe, the surface of the polytetrafluoroethylene layer is not damaged, and the process is simple.

In order to achieve the purpose, the invention adopts the following scheme: 1. a manufacturing process of a steel lining polytetrafluoroethylene pipeline comprises the following steps:

A. assembling a steel pipe and a flange, wherein the steel pipe and the flange are welded in a socket joint mode, and two O-shaped sealing grooves are machined on the sealing surface of the flange to complete welding;

B. performing inner surface treatment, namely performing surface shot blasting, iron sand spraying and acid washing, and sealing flanges at two ends;

C. air pressure test, namely testing whether air leakage exists or not through 0.8MPa air pressure to ensure that no air holes and no leakage points exist at the welded part of the steel pipe and other places integrally;

D. the polytetrafluoroethylene tube is pushed and pressed, one end of the polytetrafluoroethylene tube body is fixed, the other end of the polytetrafluoroethylene tube body is fixed on a traction device through a steel wire rope, the steel wire rope penetrates through the steel tube, the traction device stretches at a constant speed, the polytetrafluoroethylene tube is suspended after being stretched by 10% -12%, and the polytetrafluoroethylene tube is kept in a traction state all the time;

E. surface treatment, namely polishing the surface of the stretched polytetrafluoroethylene tube by using fine sand paper, washing the surface by using acetone, drying the surface by using air, performing surface treatment by using a sodium-naphthalene complex, coating a sodium-naphthalene complex solution on the surface of the polytetrafluoroethylene tube by using a polyethylene brush, uniformly coating the sodium-naphthalene complex solution along one direction, and finally, treating the surface residues of the polytetrafluoroethylene tube by using acetone until the surface is completely dried;

F. and (3) forming, namely sleeving a steel pipe on the lifted polytetrafluoroethylene pipe, loosening the traction device, tightly lining the polytetrafluoroethylene pipe in the steel pipe, putting the lined pipe into an oven for stress treatment at 10-12%, and finally turning over for forming after the treatment for 3.5-4 hours.

Furthermore, in the step A, the flange opening of the steel pipe adopts R-angle transition, the flange is a flange with a convex surface on a sealing surface, and the R-angle transition is adopted to ensure that the pipeline expands to extrude the tetrafluoro surface to generate shearing force to damage the tetrafluoro layer along with the rise of the external temperature after the pipeline is installed.

Further, the inner diameter ratio of the polytetrafluoroethylene tube in the step D is steelThe inner diameter of the pipe is 1-1.5mm large, and the density of the polytetrafluoroethylene pipe is more than 2.16-2.2 g/cm³The permeability of the pipeline medium can be enhanced, and the service life is prolonged.

And further, in the step E, coating the sodium-naphthalene complex solution on the surface of the polytetrafluoroethylene tube, wherein the thickness of the solution after brushing is 0.55-0.6 mm.

Has the advantages that: the invention has simple process, the inner wall is a single polytetrafluoroethylene layer, and the purity of the pipeline in the medium input process is ensured not to change; no gap exists between the polytetrafluoroethylene and the steel pipe, a vacuum state can be established, the polytetrafluoroethylene and the steel pipe are completely adhered, no matter how the temperature of a fluid medium changes, the polytetrafluoroethylene and the steel pipe cannot displace, and therefore bubbling or breakage cannot occur, meanwhile, the polytetrafluoroethylene and the steel pipe cannot be deflated by negative pressure, and the polytetrafluoroethylene and the steel pipe can be used for a long time under the full vacuum condition below 180 ℃.

Drawings

FIG. 1 is a drawing schematic of a polytetrafluoroethylene tube according to the invention.

Labeled as: 1. fixing device, 2, clamping die, 3, polytetrafluoroethylene tube, 4, steel tube, 5, steel wire rope, 6 and traction device.

Detailed Description

The invention will be described in further detail below with reference to the figures and specific embodiments.

Referring to fig. 1, the embodiment provides a process for manufacturing a steel-lined polytetrafluoroethylene pipeline, which includes the following steps: A. the steel pipe 4 is assembled with the flange, the steel pipe and the flange are welded in a socket joint mode, the flange opening of the steel pipe is in R-angle transition mode, the flange is a flange with a convex surface, two O-shaped sealing grooves are machined on the sealing surface of the flange, and welding is finished; B. performing inner surface treatment, namely performing surface shot blasting, iron sand spraying and acid washing, and sealing flanges at two ends; C. air pressure test, namely testing whether air leakage exists or not through 0.8MPa air pressure to ensure that no air holes and no leakage points exist at the welded part of the steel pipe and other places integrally; D. the inner diameter of the polytetrafluoroethylene pipe is 1-1.5mm larger than that of the steel pipe, and the density of the polytetrafluoroethylene pipe is more than 2.2g/cm³One end of the polytetrafluoroethylene tube body is fixed with the fixing device 1, the other end is fixed on the traction device 6 by a steel wire 5 rope,a steel wire rope 5 penetrates through the steel pipe 4, the traction device 6 stretches at a constant speed, the polytetrafluoroethylene pipe 3 is stretched by 10% through the arranged clamping die 2 and then pauses, and the polytetrafluoroethylene pipe 3 is kept in a traction state all the time; E. surface treatment, namely polishing the surface of the stretched polytetrafluoroethylene tube by using fine sand paper, washing the surface by using acetone, drying the surface by using air, performing surface treatment by using a sodium-naphthalene complex, coating a sodium-naphthalene complex solution on the surface of the polytetrafluoroethylene tube by using a polyethylene brush, uniformly coating the sodium-naphthalene complex solution along one direction, wherein the thickness of the solution after being brushed is about 0.6mm, finally, completely treating the surface residues of the polytetrafluoroethylene tube by using acetone until the surface is completely dried, and coating glue, namely epoxy polyamide and other adhesives on the surface; F. and (3) forming, namely sleeving a steel pipe on the stretched polytetrafluoroethylene pipe, loosening the traction device, tightly lining the polytetrafluoroethylene pipe in the steel pipe, putting the lined pipe into an oven for stress treatment at 50 ℃, and finally turning over for forming after 4 hours.

In this example, the sodium-naphthalene complex was prepared in advance by placing 125g of sublimed naphthalene in a three-necked flask, adding 100g of dried, peroxide-removed tetrahydrofuran, stirring to dissolve, adding 25g of sodium, and stirring until the sodium was completely dissolved

Although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that various changes in the embodiments and/or modifications of the invention can be made, and equivalents and modifications of some features of the invention can be made without departing from the spirit and scope of the invention.