SU1713828A1 - Mechanism for protecting internal surfaces of pipelines against corrosion - Google Patents

Abstract

The invention relates to the construction and operation of trunk and distribution networks of pressure and non-pressure pipelines. The purpose of the invention is to improve the quality of the coating. The unit is equipped with a system for introducing the main hose into the Bojpi pipeline, which is an extruder. and an additional hose injection system. Both systems are interconnected by a compensator with pulling rolls that feed the coating to the means of fixing the sleeve on the inner surface of the pipeline. The latter is equipped with a device for transporting the sleeve inside the pipeline. 3 hp f-ly. 6 Il.

Description

The invention relates to the construction and operation of trunk and distribution networks of pressure and non-pressure pipelines, in particular, to a device for protecting the internal surface from corrosion.

The aim of the invention is to improve the quality of pipeline coating.

FIG. 1 noKaaatfa is a schematic diagram of the unit to protect the internal surface of pipelines from corrosion; nafig.2

—Nozzles applying a coating to the means for securing the sleeve to the internal surface of the pipeline; on fit.Z

—section A-A in FIG. 2; figure 4 - supply system working agent in the pipeline; Fig. 5 illustrates a device for transporting a sleeve inside a pipeline; Figure 6 is a device for insulating the ends of a pipeline.

The unit for protection of the internal surface of pipelines from corrosion consists of a system for inserting the main hose into the pipeline, which is an extruder 1 by the canteen, and a system for inserting an additional hose into the pipeline, made in the form of an extruder 2 (head) for fastening the sleeve on the inner surface of the pipeline 4. Both Systems 1 and 2 are interconnected by means of a compensator 5 installed behind them and pulling rolls 6 feeding the coating onto the means 4 for securing the sleeve, provided with a device 7 for transporting the sleeve inside the pipeline.

The extruder of the system 1 is designed to produce a molten plastic squeezed into the head 8, and the extruder of the system 2 is used to obtain a melt of glue, also extruded into the head 8, where the two-layer tubular billet is formed. which is then fed to the compensator 5.

A device 7 for transporting the sleeve inside the pipeline consists of a ring 9 with sockets 10 on the outer surface, on one side of which a membrane 11c is located with a rubber gasket 12 having slots 13, and on the other side brackets 14 with clamps 15. Rotatable balls are freely located in sockets 10 sixteen.

The inner rolls 6 have a semicircular annular recess 17 in the middle part and are equipped with cooled Cheeks 18 and a pipe 19 with devices 20 attached thereto for feeding and removing working agents. The outer diameter of the pipe 19 corresponds to the dimensions of the notches 17 in the middle part of the rolls 6, which in turn are provided with rubber sliding rings 21 for closing the semi-circular annular notches.

The device for isolating the ends of the pipelines 22 consists of a housing 23 with a plug 24. to which a pipe 25 is attached, provided with openings 26 and 27 and a diaphragm 28.

The device 22 also has supply and discharge units for the working agent 29. For clamping the end of the sleeve, which is passed through the pipeline, serves the device 30, which is installed on the side of the pipeline opposite to the pull rolls 6. A removable cap 31 with a nozzle 32 for supplying the working agent is installed between the pull rollers and the device for transporting the sleeve. ,

The unit works as follows.

Before the initial end of the new pipeline or before cutting the old pipeline, which are to be protected, the unit is installed, connected to the energy and technological parameters.

Before starting the process of producing a two-layer tubular film blanks extruders 1 and 2 and annular film. The head 8 is heated to a predetermined temperature, after which granulated mass is loaded into the brakes and the processing begins (extruder 2 is fed with glue granules instead of plastic). From extruders 1 and 2, homogeneous melts of plastics and glue come out, which are pressed through the head 8 and out of it in the form of a two-layer film sleeve, the outer layer of which is formed by glue and the inner layer by polyethylene.

After exiting the head, the film sleeve is formed, cooled, folded and fed to the compensator 5 and then to the pull rolls 6, which feed the sleeve to means for securing the 4 sleeves to the inner surface of the pipeline.

In compensator 5, the film is stretched between rows of fixed and movable rollers arranged in such a way that at the outlet of the compensator the end

5 of the film could be lowered from the stationary roller of the compensator above the two-roller pull device (Fig. 2) mounted in front of the insulated pipeline. A compensator is needed in the device in order

0 in order to be able to fill the film into the gap between the rolls of 6 tons of the host device (Fig. 2) without stopping the process of obtaining the film on the film line.

Semicircular grooves of 17 both rollers

5 t of the lifting device is covered with rubber rings 21.

A device for transporting the sleeve inside the pipeline (Figure 5) is pushed into the pipeline after

0 the end of the flat film will be pulled through the slot 13 of the membrane 11 and the gasket 12, clamped in clamps 15, which with the film will be installed in the brackets 14. After fixing the end of the film in the fixture

5 for transporting the sleeve, the system is pushed into the interior of the pipeline, the opening of which is subsequently closed by a removable plug 31, consisting of two parts, forming between them a slit for pulling the flat film sleeve. In one of the parts of the plug, a pipe 32 for supplying the working agent to the space between the plug and the device for transporting the sleeve is provided. .

5 Then, the drive of the rollers of the main device is turned on and at the same time air is supplied with a pressure of 0.3 MPa through the nozzle 32 of the removable plug. Under influence . compressed air a device for transporting the sleeve moves the film sleeve along the pipeline until the device leaves the pipeline. After the device leaves the pipeline, the compressed air is turned off. Turns off

5, the rolls drive also 6 tons of the baffle device installed in front of the pipeline, and the film line stops. The end of the film is released from the clamps 15, is pulled out of the slots 13 of the membrane 11 and the gasket 12, and is filled into the gap between the rollers of the pulling device installed at the exit of the pipeline. Then, with the diluted rolls of both the two devices, inside the film (from the first

5, the tapering device the film is cut by a knife by hand so that the end of the film protrudes somewhat from the rolls of the tastering device), the pipe 19 of the working agent supply system is introduced into the pipeline

(pre-thread, this rubber

rings 21. covering the semicircular undercut 6 of the first ton of the device, are shifted in the working surface of the rolls), after which the rolls 6 of the two pulling devices are shifted and clamp the film with the tube 19 inserted into them.

After that, the cheeks 18 of both pulling devices are installed so that the free end of the folding cheeks is flush with the internal diameter of the steel pipe, cold water is connected to the cheeks.

Then a hot working agent with a temperature of 90-95 ° C under a pressure of 0.3 MPa is pumped through the tube 19 into the sleeve, under the influence of which the film sleeve is heated, swells and presses against the inner surface of the pipeline.

When the film is heated to 90-95 ° C, the adhesive film melts, since its melting point in the case of sevilen is below this temperature, and the plastic (for example, polyethylene) only softens, because its melting point is above 95 ° C, which allows inflate the film sleeve in the field of high-elastic. deformations and glue the plastic to the inner surface of the pipeline. After the film has been blown up, the hot agent film inside the film sleeve stops and the hose immediately starts pumping cold agent under a pressure equal to the pressure of the hot agent to cool the film to a temperature of 40-50 ° C.

Then, the ends of the cooled film after depressing the rollers of the pulling devices are released and cut off so that the length of the ends of the circumference of the pipeline rto from the pipe ends of the film rto is equal to the wall thickness of the steel pipe or if the flanges are attached to the pipe ends : th pipe and flange height.

After that, a tube 24 of the system for facing the ends of metal pipes (Fig. 6) is inserted into the pipeline from both its ends, the system housing 22 is fixed to the metal pipe and through the system of holes 26 and 27 and valves (shown conventionally) into the rubber diaphragm 28 water under pressure of 0.3 MPa with a temperature of 9095 ° C. The heated film under the action of the expanding diaphragm is deformed and glued along the entire circumference to the end of the pipe (or to the surface of the flange).

Then, under the same pressure, cold water is pumped through the diaphragm and the film is cooled to a temperature of 4050 ° C. When the film has cooled, the cold water supply is stopped and the fixtures are removed from the pipeline. The pipeline is ready for operation.

The invention provides the possibility of coating long pipeline sections, high quality of coating, a significant reduction in the labor intensity of processes, simplifies the process of corrosion protection of the internal surface of the pipeline, provides the ability to connect individual isolated sections in pipelines of any length by covering the ends of metal pipes with polyethylene.

Invention Formula

Claims (4)

1. An assembly to protect the internal surface of pipelines from corrosion, which contains a system for inserting a main hose into a pipe, which is an extruder with a HEAD, a system for inserting an additional hose into the pipeline, a system for feeding the working agent into the pipeline, and means for securing the hose to the internal surface of the pipeline, tl and h ay u i and so. that, with the purpose of improving the quality of the coating, the system for inserting an additional hose into the pipeline is made in the form of an extruder connected to the extruder head of the injection system into the pipeline of the main hose, and the unit is equipped with a compensator and drag rollers, and the means for securing the sleeve are provided with a device for transporting the sleeve inside the pipeline. 2. The unit according to claim 1, wherein the device for transporting the sleeve inside the pipeline is made in the form of a ring with sockets on the outer surface and a membrane located on one side and a gasket with slots on the other hand, brackets with clamps, with Free-rotating balls in the sockets. 3. The unit according to claim 1, in order that the pull rollers of the means for fixing the sleeve have an annular recess in the middle part, are equipped with cooled cheeks and a pipe with devices for feeding and removing working agents, the outer diameter of which corresponds to the diameter of the grooves in the middle part of the rolls, and two rubber sliding rings to close the ring grooves. 4. The unit according to claim 1, wherein it is provided with a device for isolating the ends of the pipelines, comprising a housing, a stopper with a pipe attached thereto, provided with apertures, and a diaphragm with supply nodes and disqualification of working agents. Phie s one FIG. four