CN112895407B

CN112895407B - Thermoplastic pipeline expanding device

Info

Publication number: CN112895407B
Application number: CN202110106468.9A
Authority: CN
Inventors: 何虹钢; 刘光平; 陈逸鹏; 宋鑫
Original assignee: Yibin University
Current assignee: Yibin University
Priority date: 2021-01-26
Filing date: 2021-01-26
Publication date: 2023-04-14
Anticipated expiration: 2041-01-26
Also published as: CN112895407A

Abstract

The invention relates to a thermoplastic pipeline expansion device, and belongs to the field of pipeline construction. The technical scheme is as follows: the whole base is in a disc shape, an oil cylinder is radially arranged on the base, the base axially fixes the rotary drum, and the inner cavity of the rotary drum is communicated with the cavity of the oil cylinder through a cavity of the base; the sliding sleeve is arranged outside the rotary drum; the oil cylinder comprises a cylinder body and a piston rod, the cylinder body is connected with the base, and the piston rod is provided with a top shoe; one end of the pull rod is hinged with the top boot, and the other end of the pull rod is hinged with the sliding sleeve; the end of the extending end of the rotating cylinder is provided with an adapter which is connected with a hydraulic pipeline. The invention restrains the synchronous expansion of a plurality of top shoes through a mechanical structure, prevents the deflection damage of the thermoplastic pipeline and is beneficial to the dimension of the expanded pipeline to meet the design requirement; the pipeline expanding operation with different pipe diameters can be realized by arranging the oil cylinder or the sliding sleeve to be limited at different positions, and the adaptability of the equipment is strong.

Description

Thermoplastic pipeline expanding device

Technical Field

The invention relates to the field of pipeline construction, in particular to diameter expanding construction of a thermoplastic pipeline.

Background

Polyvinyl chloride pipe, polyethylene pipe, polypropylene pipe, polyformaldehyde pipe etc. have advantages such as with low costs, corrosion-resistant, construction of being convenient for, and the wide application is in fields such as oil and gas transmission, city gas, water pipe network. At present, the pipelines are mainly connected in a hot melting butt joint mode, namely, the end parts of the pipelines are extruded together after being heated and softened. The construction of the connection mode is simpler, but the axial strength of the hot-melt connection part is lower due to the limitation of the characteristics of the polymer material; and the extruded part of the pipeline leaves a convex annular residue, so that the pipe cleaner is limited from passing through, and the pipeline is difficult to clean. This kind of connected mode, the convex cyclic annular of connection position is remained, is unfavorable for setting up the winding layer at the pipeline skin. In addition, due to the structural limitation of the two-section clamp of the pipeline, the large-caliber thin-wall pipeline is difficult to be connected in a hot-melting butt joint mode.

The flexible composite pipeline has excellent temperature resistance, good flexibility, light weight, low cost, outstanding corrosion resistance and permeation resistance, and is widely applied to the petrochemical industry. The pipeline mainly comprises an inner liner, a reinforcing layer and a protective layer from inside to outside. The inner liner, also called the transfer layer, usually consists of crosslinked polyethylene or polyethylene, having resistance to the penetration by small molecules; the reinforced layer is formed by winding polyester fibers, glass fibers, aramid fibers, carbon fibers and other fiber materials in a staggered manner, so that the risk of hydrogen sulfide stress cracking is low, and the bearing capacity is high; the protective layer is composed of cross-linked polyethylene or polyethylene, and has excellent temperature resistance.

The connecting method of the composite material pipeline generally comprises two main types of mechanical pressing mode and non-mechanical pressing mode. The principle of the mechanical compression mode is that all layers of the composite pipe are compressed to the joint piece under the mechanical action, so that the axial load transmission is realized while the sealing is realized. Mechanically pressing and connecting, namely inserting a pagoda-type joint of a metal pipe fitting into the composite pipeline; then, a metal sleeve is sleeved outside the pipeline, and the pipeline is tightly pressed by screwing the metal sleeve. However, the high-pressure flexible composite pipe has the reinforcement layer, and the structure of the reinforcement layer is easily damaged by adopting a mechanical compression mode. Particularly, for a flexible composite pipe with higher bearing capacity and a reinforcing layer made of a composite material with higher brittleness, once the reinforcing layer is damaged, load transmission is weakened, the pressure bearing capacity is reduced, and leakage accidents are easy to happen. The non-mechanical compaction mode is a layered connection mode, and the composite pipelines are connected layer by layer. The inner liners are mainly connected in a hot-melt butt joint mode, namely the end parts of the pipelines are heated and softened and then extruded together to achieve a connecting effect. However, the connection method also has the problems of low connection strength and protruding annular residues.

Based on the technical background, related scholars propose a diameter-expanding connection method for thermoplastic pipelines; namely, one end of the pipeline is heated and softened, then the diameter is expanded, then the pipeline to be connected is sleeved, and the heating is continued through an electric heating wire and the like, so that the butt joint of the two sections of pipelines is realized. The connecting mode has high strength, and no convex annular residue exists in the pipe, thereby being beneficial to the pipe cleaning operation of the pipeline. Through research, the following patent technologies are mainly used for expanding the diameter of the pipeline at present.

Patent CN204661780U discloses a pipeline expanding device, which comprises an inner pipe, an expanded pipe part, a liquid nitrogen supply device, a liquid nitrogen collecting device and a pipeline, wherein the liquid nitrogen supply device is connected with one end of the inner pipe, the liquid nitrogen collecting device is connected with the other end of the inner pipe, the expanded pipe part is arranged between two ends of the inner pipe, the expanded pipe part comprises a metal pipe, fins and an insulator, the fins are arranged on the metal pipe, and the insulator is arranged outside the metal pipe between the fins; the inner tube comprises a hose and an insulator, wherein the insulator is arranged outside the hose; the inner pipe is connected with the diameter-expanding part through a joint, the inner pipe is arranged in the pipeline, when the diameter-expanding part is placed at a position needing diameter expansion in the pipeline, the pipeline is filled with water, the liquid nitrogen supply device is started to input liquid nitrogen through one end of the inner pipe, and the liquid nitrogen flows into the liquid nitrogen collecting device through the inner pipe and the diameter-expanding part and the inner pipe. The scheme requires that a construction pipe section is filled with water; liquid nitrogen is required to be conveyed to the diameter expanding part through the inner pipe and conveyed to the outlet of the pipeline for collection through the inner pipe. Therefore, it is difficult to use the solution for pipes that do not have water filling and draining conditions.

The patent CN210919606U discloses a hydraulic system for pipe end diameter expansion of a spiral pipe, which comprises a frame, a pair of diameter expansion modules connected to the frame in a sliding manner, and a diameter expansion inclined block arranged between the two diameter expansion modules and used in cooperation with the diameter expansion modules, wherein the diameter expansion inclined block is driven by an oil cylinder, an oil way pipeline is connected to the oil cylinder, one end of the oil way pipeline is connected with an oil tank, the oil way pipeline comprises a low-pressure large-flow oil way pipeline and a high-pressure small-flow oil way pipeline, and a two-position four-way electromagnetic reversing valve and a three-position four-way electromagnetic valve for switching oil flow paths are arranged between the low-pressure large-flow oil way pipeline and the high-pressure small-flow oil way pipeline; an adjustable pressure relay is arranged on the high-pressure small-flow oil way pipeline. According to the technical scheme, two independent hydraulic output units are adopted, different requirements of different working processes on working pressure and moving speed are met according to automatic conversion of required working states, the capacity is saved, the efficiency is improved, the non-working state and the non-pressure output oil pump are in a no-load state, the consumption of electric energy can be reduced, and the loss of the oil pump is reduced. However, the scheme adopts the inclined block as an actuating mechanism, and the expanding stroke is limited; further, the diameter of the pipe cannot be expanded simultaneously in the circumferential direction, and it is difficult to ensure the roundness of the pipe after the diameter expansion.

Patent CN204934380U discloses a pipe end hydraulic pressure cold expanding machine, includes: the device comprises a hydraulic system, a bracket, an outer tire, an inner tire, a vertical guide block, a support tube, a guide rod and a position sensor. The hydraulic system is arranged on the support, and a piston rod of the hydraulic system is fixedly connected with the rear end of the inner tube. The surface of the inner tube is provided with a plurality of inclined planes distributed around the inner tube, and the inclined planes are provided with T-shaped grooves. The inner side of the outer tire is provided with a T-shaped block matched with the T-shaped groove, and the T-shaped block is matched in the T-shaped groove. The supporting tube is fixed on the bracket, and the vertical guide block is matched with a T-shaped groove at the front end of the supporting tube. The vertical guide block is fixedly connected with the outer tire. The guide rod is connected with the piston rod, and the position sensor is fixed on the support. The scheme adopts an inclined block matched with a T-shaped groove as an actuating mechanism, and the expanding stroke is limited; further, the diameter of the pipe cannot be expanded simultaneously in the circumferential direction, and it is difficult to ensure the roundness of the pipe after the diameter expansion.

The patent CN209903918U discloses a pipeline joint coating heat shrinkable sleeve expanding device which comprises a base, a support, a hydraulic cylinder, a pressure head, a connecting rod, a lifting seat and an expanding die; the base is fixed on the horizontal ground, and the expanding die and the bracket are fixedly arranged on the base; the main body part of the expanding die is of a cylindrical structure; a cross beam is arranged at the top end of the support, and a hydraulic cylinder is installed on the cross beam; the hydraulic cylinder is in an inverted state, and a pressure head is arranged at the lower end of a telescopic arm of the hydraulic cylinder; the central axis of the pressure head is coincided with the central axis of the expanding die; the lifting seat is arranged below the pressure head and connected with the pressure head through a connecting rod, the pressure head, the connecting rod and the lifting seat form an integrated frame, and a center hole matched with the outer diameter of the expanding die is formed in the lifting seat. According to the technical scheme, the conical expanding die is plugged into the cross-linked polyethylene pipeline in an axial extrusion mode to expand the pipeline. Due to the structural particularity of the technical scheme, the diameter expansion operation can be carried out on a shorter section of pipeline only; and when the axial resistance of the pipeline to be expanded is overlarge, the pipeline is easy to bend and cannot be sleeved into the conical expanding die.

In summary, the prior art mainly performs diameter expansion operation on the metal pipeline to eliminate the stress at the welding part; and expanding the diameter of the thermoplastic pipe by adopting a conical die extrusion mode. Related prior art, it is difficult to adapt to the hole enlargement construction of thermoplastic pipe. Therefore, the invention provides the diameter expanding method and tool for the thermoplastic pipe, which have practical significance and application prospect, and the related technology has great application value.

Disclosure of Invention

The purpose of the invention is as follows: the expanding tool for the thermoplastic plastic pipe is provided, and the problems that the expanding degree of the existing pipeline expanding technology is small, the roundness of a pipeline after expanding is low, the expanding of the end part of a long pipeline is not suitable and the like are solved; the problems that the existing thermoplastic pipeline is low in hot-melt butt joint axial strength and the connection part is protruded and annular in residue are solved.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows.

The utility model provides a thermoplasticity pipeline expanding unit, includes top boots, base, hydro-cylinder, pull rod, rotary drum, sliding sleeve and adapter, its characterized in that: the whole base is in a disc shape, an oil cylinder is radially arranged on the base, the base axially fixes the rotary drum, and the inner cavity of the rotary drum is communicated with the cavity of the oil cylinder through a cavity of the base; the sliding sleeve is arranged outside the rotary drum; the oil cylinder comprises a cylinder body and a piston rod, the cylinder body is connected with the base, and the piston rod is provided with a top shoe; one end of the pull rod is hinged with the top boot, and the other end of the pull rod is hinged with the sliding sleeve; the end of the rotary drum extending end is provided with an adapter which is connected with a hydraulic pipeline.

Still include support and fender ring, its characterized in that: the rotary drum is fixed on the support, a bearing is arranged between the rotary drum and the support, and the bearing is a sliding bearing; and two ends of the support are provided with baffle rings which are circular and are fixed with the rotary drum through bolts.

A spring is arranged between the sliding sleeve and the base and is a compression spring, and the spring is sleeved on the rotary drum.

At least 3 oil cylinders are arranged in the circumferential direction of the base in a central symmetry mode.

The top shoe comprises an arc-shaped plate, a bus of the arc-shaped plate is parallel and level to the axis of the rotary drum, the inner side of the arc-shaped plate is connected with a piston rod of the oil cylinder, a transition section is arranged at the end part of one side, close to the pipeline, of the arc-shaped plate, and the transition section is conical or arc-shaped.

The invention has the beneficial effects that: (1) The invention realizes synchronous expansion of a plurality of top shoes through a mechanical structure, prevents the thermoplastic pipeline from deflecting, and is beneficial to the expanded pipeline size to meet the design requirement; (2) Through the special structure of the top shoe, a smooth transition section exists between the large end and the small end of the expanded diameter pipeline, so that the thermoplastic pipeline is prevented from being damaged; (3) The hydraulic drive is matched with manual adjustment of the diameter-expanding part, so that the operation is simple and convenient; (4) The oil cylinder or the sliding sleeve is arranged at different position for limiting, so that the diameter expanding operation of pipelines with different pipe diameters can be realized, and the adaptability of the equipment is strong.

Drawings

FIG. 1 is a schematic diagram of the present invention.

Fig. 2 isbase:Sub>A sectional viewbase:Sub>A-base:Sub>A of fig. 1.

Fig. 3 is a schematic view of the construction of the top shoe of the present invention.

In the figure: 1. a pipeline; 2. a top boot; 3. a base; 4. a cylinder body; 5. a piston rod; 6. a spring; 7. a pull rod; 8. a rotating drum; 9. a sliding sleeve; 10. a baffle ring; 11. a support; 12. a bearing; 13. and (6) an adapter.

Detailed Description

The present invention is not limited to the following embodiments, and the specific embodiments may be determined according to the technical solution and the actual situation of the present invention. The present invention will be described below with reference to the accompanying drawings. The positional relationship of up, down, left, right, etc. is determined in accordance with the layout direction of fig. 1 in the specification.

A thermoplastic pipeline expansion device comprises a top shoe 2, a base 3, an oil cylinder, a pull rod 7, a rotary drum 8, a sliding sleeve 9 and an adapter 13. The whole base 3 is disc type, 3 radial installation hydro-cylinders of base, 3 axial fixity rotary drums 8 of base, through 3 cavitys intercommunications of base between 8 inner chambers of rotary drum and the hydro-cylinder cavity. The sliding sleeve 9 is installed outside the drum 8, and the sliding sleeve 9 can slide in the axial direction of the drum 8. The oil cylinder comprises a cylinder body 4 and a piston rod 5, the cylinder body 4 is connected with the base 3, and the end part of the extending end of the piston rod 5 is provided with the top shoe 2. One end of the pull rod 7 is hinged with the top shoe 2, and the other end of the pull rod 7 is hinged with the sliding sleeve 9. The end part of the extending end of the rotating cylinder 8 is provided with an adapter 13, and the adapter 13 is connected with a hydraulic pipeline; support 11 is fixed, and under the rotatory condition of rotary drum 8, adapter 13 guarantees that hydraulic line normally connects.

The drum 8 is fixed to a support 11, and a bearing 12 is arranged between the drum 8 and the support 11, wherein the bearing 12 is a sliding bearing 12. Two ends of the support 11 are provided with baffle rings 10, and the baffle rings 10 are annular and fixed with the rotary drum 8 through bolts.

A spring 6 is arranged between the sliding sleeve 9 and the base 3, the spring 6 is a compression spring 6, and the spring 6 is sleeved on the rotary drum 8. After the cylinder is relieved of pressure, the spring 6 resets the top shoe 2.

At least 3 oil cylinders are arranged in central symmetry in the circumferential direction of the base 3, so that the plurality of top shoes 2 synchronously extend out, a plurality of parts of the pipeline 1 are simultaneously expanded, and the pipeline 1 is prevented from deflecting and deforming.

The top shoe 2 comprises an arc-shaped plate, a bus of the arc-shaped plate is parallel and level to the axis of the rotary drum 8, the inner side of the arc-shaped plate is connected with the piston rod 5 of the oil cylinder, a transition section is arranged at the end part of the arc-shaped plate close to one side of the pipeline 1, and the transition section is conical or arc-shaped. Through the special structure of the top shoe 2, a smooth transition section exists between the large end and the small end of the expanded diameter pipeline 1, and the thermoplastic pipeline 1 is prevented from being damaged.

The principle of the invention is as follows: when the diameter expanding operation of the thermoplastic pipeline 1 is carried out, the top shoe 2 is placed in the pipeline 1, high-pressure hydraulic oil is introduced from the adapter 13, the oil enters the oil cylinder through the rotary drum 8 and the base 3 in sequence, and the oil cylinder pushes the top shoe 2 to expand outwards, so that the diameter of the pipeline 1 is expanded. After the pressure of the oil cylinder is removed, the top shoe 2 returns under the action of the compression spring 6; the pull rod 7 and the top shoe 2 are manually rotated, so that the top shoe 2 performs diameter expanding operation at different positions in the circumferential direction of the pipeline 1. The top shoe 2 is ejected for a plurality of times, the whole circumferential direction of the pipeline 1 is uniformly expanded, and the effect of expanding the diameter is achieved. Through the scheme, under the action of the pull rod 7 and the sliding sleeve 9, the plurality of top shoes 2 work cooperatively and expand synchronously, so that the thermoplastic pipeline 1 is prevented from being deflected and damaged, and the size of the expanded pipeline 1 can meet the design requirement.

Claims

1. The utility model provides a thermoplasticity pipeline expansion device, includes top boots, base, hydro-cylinder, pull rod, rotary drum, sliding sleeve and adapter, its characterized in that: the whole base is in a disc shape, an oil cylinder is radially arranged on the base, the base axially fixes the rotary drum, and the inner cavity of the rotary drum is communicated with the cavity of the oil cylinder through a cavity of the base; the sliding sleeve is arranged outside the rotary drum; the oil cylinder comprises a cylinder body and a piston rod, the cylinder body is connected with the base, and the piston rod is provided with a top shoe; one end of the pull rod is hinged with the top boot, and the other end of the pull rod is hinged with the sliding sleeve; the end part of the extending end of the rotary drum is provided with an adapter which is connected with a hydraulic pipeline;

the rotary drum is fixed on the support, a bearing is arranged between the rotary drum and the support, and the bearing is a sliding bearing; two ends of the bracket are provided with baffle rings which are annular and are fixed with the rotary drum through bolts;

a spring is arranged between the sliding sleeve and the base, the spring is a compression spring, and the spring is sleeved on the rotary drum;

at least 3 oil cylinders are arranged in the circumferential direction of the base in a central symmetry manner;