阅读说明：本技术 一种衬塑钢管的芯管剥离设备 (Core tube stripping equipment for plastic-lined steel tube ) 是由 王智勇 于 2021-07-29 设计创作，主要内容包括：本发明提供了一种衬塑钢管的芯管剥离设备,涉及管材制作与应用技术领域。该衬塑钢管的芯管剥离设备包括基座以及设置在基座上输送机构、加热机构和剥离机构；输送机构用于移动衬塑钢管,使衬塑钢管沿自身的轴线方向移动；加热机构用于加热衬塑钢管；剥离机构用于伸入衬塑钢管的内腔并剥离衬塑钢管的芯管。现有技术中并不存在剥离衬塑钢管的芯管的专用设备,本发明的衬塑钢管的芯管剥离设备,首先利用加热机构将内层芯管软化使其与外层钢管初步分离,再通过输送机构、剥离机构将内层芯管从外层钢管的内腔中完全剥离出来。(The invention provides core pipe stripping equipment for a plastic-lined steel pipe, and relates to the technical field of pipe manufacturing and application. The core pipe stripping equipment for the plastic-lined steel pipe comprises a base, a conveying mechanism, a heating mechanism and a stripping mechanism, wherein the conveying mechanism, the heating mechanism and the stripping mechanism are arranged on the base; the conveying mechanism is used for moving the plastic-lined steel pipe to enable the plastic-lined steel pipe to move along the axis direction of the conveying mechanism; the heating mechanism is used for heating the plastic-lined steel pipe; the stripping mechanism is used for extending into the inner cavity of the plastic-lined steel pipe and stripping the core pipe of the plastic-lined steel pipe. The core tube stripping device for the plastic-lined steel tube firstly utilizes a heating mechanism to soften an inner core tube so as to enable the inner core tube to be initially separated from an outer steel tube, and then completely strips the inner core tube from an inner cavity of the outer steel tube through a conveying mechanism and a stripping mechanism.)

1. The core tube stripping equipment for the plastic-lined steel tube is characterized by comprising a base (100), a conveying mechanism (200), a heating mechanism (300) and a stripping mechanism (400), wherein the conveying mechanism (200), the heating mechanism (300) and the stripping mechanism (400) are arranged on the base (100);

the conveying mechanism (200) is used for moving the plastic-lined steel pipe to enable the plastic-lined steel pipe to move along the axis direction of the steel pipe; the heating mechanism (300) is used for heating the plastic-lined steel pipe; the stripping mechanism (400) is used for extending into the inner cavity of the plastic-lined steel pipe and stripping the core pipe of the plastic-lined steel pipe.

2. The core tube stripping apparatus for plastic-lined steel tubes as recited in claim 1, wherein the conveying mechanism (200) comprises a first roller set (210), the first roller set (210) comprising two first driving rollers (211) having axes parallel to each other; the two first driving rollers (211) are used for clamping the plastic-lined steel pipe, and the rotating directions of the two first driving rollers (211) are opposite.

3. The core tube stripping apparatus for plastic-lined steel tubes as recited in claim 2, wherein the first roller set (210) further comprises a first speed reducer (212); two first driving bevel gears (2121) which are in mirror symmetry are arranged on an output shaft of the first speed reducer (212), first driven bevel gears (2111) are arranged on rotating shafts of the two first driving rollers (211), and the two first driven bevel gears (2111) are respectively meshed with the two first driving bevel gears (2121).

4. The core tube stripping apparatus for plastic-lined steel tubes as recited in claim 3, wherein the conveying mechanism (200) further comprises a second roller set, the second roller set comprising two second driving rollers having axes parallel to each other; the two second driving rollers are used for clamping the plastic-lined steel pipe, and the rotating directions of the two second driving rollers are opposite.

5. The core tube stripping apparatus for plastic-lined steel tubes as recited in claim 4, wherein the second roller set further comprises a second speed reducer; two second driving bevel gears which are in mirror symmetry are arranged on an output shaft of the second speed reducer, second driven bevel gears are arranged on rotating shafts of the two second driving rolling wheels, and the two second driven bevel gears are respectively meshed with the two second driving bevel gears.

6. The core tube stripping apparatus for plastic-lined steel tubes as recited in claim 1, wherein said heating mechanism (300) comprises a high-frequency heating ring (310), said plastic-lined steel tubes being movable through said high-frequency heating ring (310).

7. The core tube stripping apparatus for plastic-lined steel tubes as recited in claim 6, wherein said heating mechanism (300) further comprises a temperature monitoring device (320); the temperature monitoring device (320) is electrically connected with the high-frequency heating ring (310).

8. The core tube stripping apparatus for plastic-lined steel tubes as claimed in claim 1, wherein said stripping mechanism (400) comprises a tractor (410), a tie rod (420) and a grapple die (430); the tractor (410) is connected with the grapple mould (430) through the pull rod (420); tractor (410) can be followed the axis direction of lining plastic steel pipe removes, pull rod (420) are used for stretching into the inner chamber of lining plastic steel pipe, grapple mould (430) are used for peeling off the core pipe of lining plastic steel pipe.

9. The core tube stripping apparatus for plastic-lined steel tubes as claimed in claim 8, wherein said stripping mechanism (400) further comprises two drive sprockets (440) and a chain (450); two ends of the chain (450) are respectively arranged at the front end and the rear end of the tractor (410), and the chain (450) is wound on the two driving chain wheels (440).

10. The core tube stripping apparatus for plastic-lined steel tubes as claimed in claim 9, wherein said tie bar (420) and said grapple die (430) are removably attached.

Technical Field

The invention relates to the technical field of pipe manufacturing and application, in particular to core pipe stripping equipment for a plastic-lined steel pipe.

Background

In recent years, the application range of plastic-lined steel pipes in China is continuously expanded, and the plastic-lined steel pipes are basically the preferred materials regardless of various pipelines hung in the air in basement of a community or tap water pipelines of high-rise communities laid by secondary pressurized water supply companies, and are widely applied to water supply, fire fighting, drainage and other use occasions.

At present, the general production process of the plastic-lined steel pipe comprises the following steps: according to the requirements, seamless steel pipes or welded steel pipes made of various materials are used as base pipes (namely 'outer layer steel pipes'), welding ribs are removed from the inner walls of the welded steel pipes, then phosphating is carried out on the inner surfaces of the base pipes, and then food-grade polyethylene pipes (namely 'inner layer core pipes') with the same inner diameter as the base pipes are lined.

Wherein, the inner core tube is manufactured by adopting a double-layer co-extrusion process, and the outer layer is made of very thin bonding resin. During production, the two ends of the outer steel pipe are sealed to be pressurized by blowing air, meanwhile, the high-frequency equipment is moved at a constant speed to perform annular rapid heating on the outer steel pipe, then the outer steel pipe is cooled to a temperature below the crystallization temperature by using cooling liquid, and then the air pressure in the lining plastic steel pipe can be removed.

However, in the production process of the plastic-lined steel pipe, the inner core pipe and the outer steel pipe are not firmly bonded or air bubbles are easily generated in the interlayer due to the environment, materials or processes. At the moment, the inner core pipe and the outer steel pipe are usually scrapped together, so that great resource waste and environmental protection problems are brought to the society and the environment.

Disclosure of Invention

The invention aims to provide core tube stripping equipment for a plastic-lined steel tube, which is helpful for solving the technical problem.

The invention is realized by the following steps:

a core tube stripping device for a plastic-lined steel tube comprises a base, a conveying mechanism, a heating mechanism and a stripping mechanism, wherein the conveying mechanism, the heating mechanism and the stripping mechanism are arranged on the base; the conveying mechanism is used for moving the plastic-lined steel pipe to enable the plastic-lined steel pipe to move along the axis direction of the conveying mechanism; the heating mechanism is used for heating the plastic-lined steel pipe; the stripping mechanism is used for extending into the inner cavity of the plastic-lined steel pipe and stripping the core pipe of the plastic-lined steel pipe.

When the core pipe stripping equipment for the plastic-lined steel pipe is used, firstly, the plastic-lined steel pipe to be stripped is clamped on the conveying mechanism, and the conveying mechanism is started to move the plastic-lined steel pipe to the heating mechanism; then, the outer-layer steel pipe is heated to the required temperature instantly by using a heating mechanism, the resin adhered to the surface layer of the inner-layer core pipe is rapidly plasticized (the plasticizing temperature is 110-130 ℃) due to direct contact with the high-temperature outer-layer steel pipe, and then the inner-layer core pipe is gradually softened under the action of heat transfer (the softening temperature of linear low-density polyethylene is 110-130 ℃, the melting temperature is 160-180 ℃) so that the inner-layer core pipe and the outer-layer steel pipe initially form a free state of free adhesion; and then starting the stripping mechanism, wherein the conveying mechanism drives the outer layer steel pipe of the plastic-lined steel pipe to move towards one direction, and the stripping mechanism drives the softened inner layer core pipe to move in the opposite direction, so that the inner layer core pipe is completely stripped from the inner cavity of the outer layer steel pipe. Reduces the waste of products and raw materials thereof, and relieves the environmental protection problem caused by the waste of the products and the raw materials.

Further, the conveying mechanism comprises a first roller group, and the first roller group comprises two first driving rollers with axes parallel to each other; the two first driving rollers are used for clamping the plastic-lined steel pipe, and the rotating directions of the two first driving rollers are opposite. The technical effects are as follows: the plastic-lined steel pipe is clamped by the rollers, and the plastic-lined steel pipe can be stably moved on the premise of keeping high clamping stability.

Further, the first roller group also comprises a first speed reducer; two first driving bevel gears which are in mirror symmetry are arranged on an output shaft of the first speed reducer, first driven bevel gears are arranged on rotating shafts of the two first driving idler wheels, and the two first driven bevel gears are respectively meshed with the two first driving bevel gears. The technical effects are as follows: two bevel gears with the same rotation direction are arranged in the same output shaft, and then the two bevel gears are used for driving two passive bevel gears, so that the two parallel rollers are driven to rotate in opposite directions, and finally, the two rollers have absolute synchronism. Preferably, a quincunx key groove may be formed on the output shaft of the first speed reducer, or the cross section of the output shaft may be a rectangular structure, or the bevel gear may be fixedly mounted on the output shaft by a screw or other structures. In addition, the two first driving bevel gears are arranged in a mirror symmetry mode, so that the two rollers have absolute synchronism finally.

Further, the conveying mechanism also comprises a second roller group, and the second roller group comprises two second driving rollers with axes parallel to each other; the two second driving rollers are used for clamping the plastic-lined steel pipe, and the rotating directions of the two second driving rollers are opposite. The technical effects are as follows: the effect of this design and first roller train is similar, however, the design overall arrangement of two roller trains tandem has further improved the position stability of lining plastic steel pipe in the removal process.

Further, the second roller group also comprises a second speed reducer; two second driving bevel gears which are in mirror symmetry are arranged on an output shaft of the second speed reducer, second driven bevel gears are arranged on rotating shafts of the two second driving rolling wheels, and the two second driven bevel gears are respectively meshed with the two second driving bevel gears. The technical effects are as follows: this design is similar with first speed reducer's effect, utilizes a speed reducer to drive two gyro wheels counter-rotation drive lining plastic steel pipe and removes. However, the two groups of speed reducers adopt the same design layout, and the speed balance of the plastic-lined steel pipe in the moving process is further improved.

Further, the heating mechanism comprises a high-frequency heating ring, and the plastic-lined steel pipe can penetrate through the high-frequency heating ring when moving. The technical effects are as follows: the high-frequency heating ring is fast to metal heating speed, and voltage or current through adjusting high-frequency heating equipment can heat metal pipe to required temperature and rapid cooling fast, easily with temperature adjustment to suitable numerical value.

Further, the heating mechanism further comprises a temperature monitoring device; the temperature monitoring device is electrically connected with the high-frequency heating ring. The technical effects are as follows: the temperature monitoring device can monitor the temperature of the steel pipe in real time, and the control efficiency, the use safety and the reliability of the device are improved. Preferably, the temperature monitoring device can be an infrared temperature monitoring device.

Further, the stripping mechanism comprises a tractor, a pull rod and a grapple mold; the tractor is connected with the grapple mold through the pull rod; the tractor can follow the axis direction of lining plastic steel pipe removes, the pull rod is used for stretching into the inner chamber of lining plastic steel pipe, the grapple mould is used for peeling off the core pipe of lining plastic steel pipe. The technical effects are as follows: the tractor is used for providing stripping power, and the pull rod is used for extending the grapple mould to a proper position and providing traction pulling force.

Further, the peeling mechanism also comprises two driving chain wheels and a chain; two ends of the chain are respectively arranged at the front end and the rear end of the tractor, and the chain is wound on the two driving chain wheels. The technical effects are as follows: the power output combination of the driving chain wheel and the chain not only ensures the normal loading of the load, but also has certain flexibility, improves the power output stability of the stripping mechanism, and prevents the stripping failure caused by the vibration or shake in the stripping process.

Further, the pull rod is detachably connected with the grapple mold. The technical effects are as follows: the pull rod is detachably connected with the grapple mold, different grapple molds can be configured according to the plastic-lined steel pipes with different sizes, and the use requirements of various different scenes are met.

The invention has the beneficial effects that:

the core tube stripping equipment for the plastic-lined steel tube comprises a conveying mechanism, a heating mechanism, a plastic-lined steel tube stripping mechanism and a plastic-lined steel tube stripping mechanism, wherein the conveying mechanism is used for clamping the plastic-lined steel tube to be stripped; then, the outer-layer steel pipe is heated to the required temperature instantly by using a heating mechanism, the resin adhered to the surface layer of the inner-layer core pipe is rapidly plasticized (the plasticizing temperature is 110-130 ℃) due to direct contact with the high-temperature outer-layer steel pipe, and then the inner-layer core pipe is gradually softened under the action of heat transfer (the softening temperature of linear low-density polyethylene is 110-130 ℃, the melting temperature is 160-180 ℃) so that the inner-layer core pipe and the outer-layer steel pipe initially form a free state of free adhesion; and then starting the stripping mechanism, wherein the conveying mechanism drives the outer layer steel pipe of the plastic-lined steel pipe to move towards one direction, and the stripping mechanism drives the softened inner layer core pipe to move in the opposite direction, so that the inner layer core pipe is completely stripped from the inner cavity of the outer layer steel pipe. Reduces the waste of products and raw materials thereof, and relieves the environmental protection problem caused by the waste of the products and the raw materials.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a schematic view showing the overall structure of a core tube stripping apparatus for a plastic-lined steel pipe according to the present invention;

FIG. 2 is an enlarged view of a portion of FIG. 1 at A;

FIG. 3 is a front view of a first roller set and its related structure in the core tube stripping apparatus for plastic-lined steel tubes according to the present invention;

FIG. 4 is a side view (along the axis of the plastic-lined steel pipe) of the first roller set and its related structure in the core stripping apparatus for plastic-lined steel pipes according to the present invention;

fig. 5 is a partially enlarged view of fig. 1 at B.

Icon: 100-a base; 200-a conveying mechanism; 210-a first roller set; 211-a first drive roller; 2111-a first driven bevel gear; 212-a first reducer; 2121-a first drive bevel gear; 230-a cylinder; 300-a heating mechanism; 310-high frequency heating coil; 320-temperature monitoring means; 400-a peeling mechanism; 410-a tractor; 420-a pull rod; 430-grapple mold; 440-a drive sprocket; 450-a chain; 500-plastic lined steel pipes; 600-36750, and heavy wheel set.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, 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. It is to be understood that the embodiments described are only a few embodiments of the present invention, and not all embodiments. The components of embodiments of the present invention that are generally described and illustrated in the figures can be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. 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.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings or the orientations or positional relationships that the products of the present invention are conventionally placed in use, and are only used for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used solely to distinguish one from another and are not to be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal", "vertical", "overhang" and the like do not imply that the components are required to be absolutely horizontal or overhang, but may be slightly inclined. For example, "horizontal" merely means that the direction is more horizontal than "vertical" and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present invention, it should also be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Some embodiments of the invention are described in detail below with reference to the accompanying drawings. The embodiments described below and the features of the embodiments can be combined with each other without conflict.

FIG. 1 is a schematic view showing the overall structure of a core tube stripping apparatus for a plastic-lined steel pipe according to the present invention; FIG. 2 is an enlarged view of a portion of FIG. 1 at A; fig. 3 is a front view of a first roller set 210 and its related structure in the apparatus for stripping the core tube of the plastic-lined steel tube according to the present invention; fig. 4 is a side view (along the axial direction of the plastic-lined steel pipe 500) of the first roller set 210 and its related structure in the core stripping apparatus for plastic-lined steel pipes according to the present invention; fig. 5 is a partially enlarged view of fig. 1 at B. Referring to fig. 1 to 5, the present embodiment provides a core tube stripping apparatus for a plastic-lined steel tube, which includes a base 100, and a conveying mechanism 200, a heating mechanism 300 and a stripping mechanism 400 disposed on the base 100. The conveying mechanism 200 is used for moving the plastic-lined steel pipe 500 to enable the plastic-lined steel pipe 500 to move along the axis direction of the conveying mechanism; the heating mechanism 300 is used for heating the plastic-lined steel pipe 500; the stripping mechanism 400 is used to extend into the inner cavity of the plastic-lined steel pipe 500 and strip the core tube of the plastic-lined steel pipe 500.

Wherein, the conveying mechanism 200 can comprise a roller group structure, a traction pushing structure and other forms; the heating mechanism 300 may take the form of a heating coil, infrared rays, ultraviolet rays, or the like; the peeling mechanism 400 may take the form of a planer, winch, or grapple.

The working principle and the operation method of the core tube stripping equipment for the plastic-lined steel tube in the embodiment are as follows:

firstly, clamping a plastic-lined steel pipe 500 to be stripped on a conveying mechanism 200, and opening the conveying mechanism 200 to move the plastic-lined steel pipe 500 to a heating mechanism 300; then, the heating mechanism 300 is utilized to instantly heat the outer layer steel pipe to a required temperature, the resin adhered to the surface layer of the inner layer core pipe is rapidly plasticized (the plasticizing temperature is 110-130 ℃) due to direct contact with the high-temperature outer layer steel pipe, and then the inner layer core pipe is gradually softened under the action of heat transfer (the softening temperature of linear low-density polyethylene is 110-130 ℃, the melting temperature is 160-180 ℃) so that the inner layer core pipe and the outer layer steel pipe initially form a free state of free adhesion; and then the peeling mechanism 400 is started, at this time, the conveying mechanism 200 drives the outer layer steel pipe of the plastic-lined steel pipe 500 to move towards one direction, and the peeling mechanism 400 drives the softened inner layer core pipe to move in the opposite direction, so that the inner layer core pipe is completely peeled from the inner cavity of the outer layer steel pipe. Reduces the waste of products and raw materials thereof, and relieves the environmental protection problem caused by the waste of the products and the raw materials.

Before the plastic-lined steel pipe 500 is placed, the plastic-lined steel pipe 500 to be peeled is fed from the plastic-lined steel pipe lifting device 36750, and the heavy wheel set 600 is fed into the conveying mechanism 200.

In at least one preferred embodiment, further, as shown in fig. 1, 3, 4, the conveying mechanism 200 includes a first roller set 210, the first roller set 210 including two first driving rollers 211 whose axes are parallel to each other; the two first driving rollers 211 are used for clamping the plastic-lined steel pipe 500, and the rotating directions of the two first driving rollers 211 are opposite. The side wall of the first driving roller 211 is recessed, and preferably, anti-slip lines may be further disposed in the recessed portion.

Before the plastic-lined steel pipe 500 is conveyed into the conveying mechanism 200, the distance between the two first driving rollers 211 is increased by using the air cylinder 230, and after the plastic-lined steel pipe 500 is placed, the air cylinder 230 descends again to enable the plastic-lined steel pipe 500 to be clamped and fixed by the two first driving rollers 211.

In at least one preferred embodiment, as shown in fig. 1, 3 and 4, the first roller set 210 further includes a first speed reducer 212, two first driving bevel gears 2121 are arranged on an output shaft of the first speed reducer 212 in a mirror symmetry manner, first driven bevel gears 2111 are arranged on rotating shafts of the two first driving rollers 211, and the two first driven bevel gears 2111 are respectively engaged with the two first driving bevel gears 2121. Preferably, an output shaft of the first speed reducer 212 is provided in a quincunx shape, and two first driven bevel gears 2111 are slidably connected to the output shaft.

In at least one preferred embodiment, further, as shown in fig. 1, 3, 4, similar to the first roller set 210, the conveying mechanism 200 further includes a second roller set (not labeled) including two second driving rollers with their axes parallel to each other; the two second driving rollers are used for clamping the plastic-lined steel pipe 500, and the rotation directions of the two second driving rollers are opposite.

In at least one preferred embodiment, further, as shown in fig. 1, 3, 4, the second roller set further includes a second speed reducer (not labeled) similar to the first roller set 210; two second driving bevel gears are arranged on an output shaft of the second speed reducer in a mirror symmetry mode, second driven bevel gears are arranged on rotating shafts of the two second driving rolling wheels, and the two second driven bevel gears are meshed with the two second driving bevel gears respectively. Similarly, the output shaft of the second reduction gear is preferably provided in a quincunx shape, and two second driven bevel gears are slidably connected to the output shaft.

In at least one preferred embodiment, further, as shown in fig. 1 and 2, the heating mechanism 300 includes a high-frequency heating ring 310, and the plastic-lined steel pipe 500 can pass through the high-frequency heating ring 310 when moving. Preferably, the high-frequency heating coil 310 is disposed between the first and second roller groups 210 and 210.

In at least one preferred embodiment, further, as shown in fig. 2, the heating mechanism 300 further comprises a temperature monitoring device 320; the temperature monitoring device 320 is electrically connected to the high-frequency heating coil 310.

In at least one preferred embodiment, further, as shown in fig. 1, 5, the stripping mechanism 400 includes a tractor 410, a drawbar 420, and a grapple mold 430; the tractor 410 is connected with the grapple mold 430 through a pull rod 420; the tractor 410 can move along the axis direction of the plastic-lined steel pipe 500, the pull rod 420 is used for extending into the inner cavity of the plastic-lined steel pipe 500, and the grapple mold 430 is used for stripping the core pipe of the plastic-lined steel pipe 500.

In at least one preferred embodiment, further, as shown in FIG. 5, the peeling mechanism 400 further includes two drive sprockets 440 and a chain 450; the two ends of the chain 450 are respectively disposed at the front end and the rear end of the tractor 410, and the chain 450 is wound around the two driving sprockets 440.

In at least one preferred embodiment, further, as shown in fig. 2, the pull rod 420 and the grapple mold 430 are detachably connected, and in practical use, the grapple mold 430 is selected according to the diameter of the plastic-lined steel pipe 500 to be processed.

Specifically, the use steps of the core tube stripping equipment for the plastic-lined steel tube of the embodiment specifically include:

1. firstly, the air cylinder 230 is used for lifting the rollers above the first roller group 210 and the second roller group in the conveying mechanism 200, then the roller 36750, the plastic lined steel pipe 500 to be stripped on the heavy wheel group 600 is sent into the space between the rollers of the conveying mechanism 200, and then the air cylinder 230 is lowered to clamp the plastic lined steel pipe 500 between the rollers.

2. A desired pressure between the two first driving rollers 211 is set (the air cylinder 230 may be employed in the present embodiment).

3. The heating mechanism 300 is turned on. The linear speed of the movement of the conveying mechanism 200 and the peeling mechanism 400 is set according to the required warming time of the heating device, and the linear speed of the movement of the peeling mechanism 400 must be ensured to be slightly faster than the linear speed of the movement of the conveying mechanism 200 by about 10 percent, so that the core tube is stretched to be longer.

4. The first speed reducer 212 is started, the front end of the plastic-lined steel pipe 500 passes through the high-frequency heating ring 310, the heating mechanism 300 is closed, due to high-frequency heating, the temperature of the outer-layer steel pipe at the moment is required to reach the required temperature, so that the surface layer bonding resin (the plasticizing starting temperature is 110 ℃ -130 ℃) of the inner-layer core pipe is instantly plasticized, the outer-layer steel pipe and the inner-layer core pipe are in a free bonding state, at the moment, the inner-layer core pipe is influenced by heat transfer and becomes softer, and because the polyethylene material of the inner-layer core pipe is a hot poor conductor, the skin of the inner-layer core pipe is in contact with the outer-layer steel pipe, but the body of the inner-layer core pipe cannot reach a melting state.

5. The tractor 410 is quickly started, the pull rod 420 quickly penetrates through the pipe orifice of the plastic lined steel pipe 500 for the required length, and the tractor 410 is stopped.

6. Installing a grapple mold 430 with a required size, rapidly inserting the grapple mold 430 into an interlayer between the outer-layer steel pipe and the inner-layer core pipe by using a special tool, enabling the port of the inner-layer core pipe to be wrinkled and shrunk to be conical, and then fixedly connecting the grapple mold 430 with the pull rod 420.

7. The tractor 410 is started to move the grapple mold 430 to the opposite direction of the plastic lined steel pipe 500 conveying direction until the grapple mold 430 passes through the high frequency heating ring and then the tractor 410 is stopped to prevent the heating ring from heating the grapple mold 430.

8. The heating mechanism 300 is started, and the conveying mechanism 200 and the peeling mechanism 400 are simultaneously and rapidly started, at this time, the plastic-lined steel pipe 500 passes through the high-frequency heating ring 310 to move at a constant speed, and the grapple mold 430 is pulled in the direction opposite to the moving direction of the plastic-lined steel pipe 500, so that the body of the outer-layer steel pipe can be rapidly peeled off after the skin adhesive resin of the inner-layer core pipe is plasticized.

9. When the whole plastic-lined steel pipe 500 passes through the high-frequency heating ring 310, the core tube stripping work of the plastic-lined steel pipe 500 is naturally completed.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.