CN105290177A

CN105290177A - Hot bending forming technology of large-caliber thick-walled pipe filled with sand cores through heat in supplementing manner

Info

Publication number: CN105290177A
Application number: CN201410266721.7A
Authority: CN
Inventors: 李诤; 陈杨
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-06-16
Filing date: 2014-06-16
Publication date: 2016-02-03

Abstract

The invention discloses a hot bending forming technology of a large-caliber thick-walled pipe filled with sand cores through heat in a supplementing manner. Under the cold state condition, the sand cores with the small volume expansion coefficient are added into an inner cavity of the pipe as filler, when the pipe is heated to the bending temperature, the heat-state sand cores in the pipe can deposit to a certain degree along with thermal expansion deformation of the pipe, and then the inner cavity of the pipe is filled with cold-state sand cores in a supplementing manner till the inner cavity of the pipe is full, and the pipe wall of a bent pipe section can be fully supported; and accordingly the bent section of the pipe cannot distort or deform in the bending and pressing process, and the success rate of pipe bending and the quality of finished products are effectively improved.

Description

A kind of large-sized heavy-wall tube hot bending forming technique vulcanizing sand loading core

Technical field

The present invention relates to a kind of large-sized heavy-wall tube hot bending forming technique vulcanizing sand loading core, it is characterized in that in heavy caliber thick wall pipe fitting inner chamber, filling the less core of the cubic expansion coefficient as filler in the cold state.After pipe fitting is heated, because plumbing dimensions changes, again need add cold conditions core with the space occurred after filling up hot core sedimentation, make tube wall enough supports can be obtained by during bending process, thus guarantee that pipe fitting bending section distorting transformation can not occur curved pressing through in journey, that improves heavy caliber thick wall pipe fitting is bent into power.

Background technology

At present, due to the increasing of diameter and wall thickness when large-sized heavy-wall tube bends in the cold state, need the deformation drag that overcomes also increasing, thus cause bending required press tonnage and also increase thereupon.As needed bending process heavy caliber thick wall pipe fitting in the cold state, then mean larger investment, and press power utilization is low, can produce die size large, process costs is high, and job safety hidden danger is large waits series of problems.Adopt hot bending forming technique can reduce the deformation drag of pipe fitting, thus press tonnage demand can be reduced, and significantly reduce process costs.But when bending pipe fitting under hot, because the deformation drag of tube wall significantly reduces, in bending process process, therefore very easily there is the phenomenon be crushed by curved pressure pipe section tube wall, thus cause this pipeline section caliber ovality overproof, cause damage.

Summary of the invention

In order to solve heavy caliber thick wall pipe fitting recurrent pipe fitting distorting transformation problem when bending process, the present invention proposes a kind of large-sized heavy-wall tube hot bending forming technique vulcanizing sand loading core.The core concept of this technology in tube intracavity, fills the little core of the cubic expansion coefficient in the cold state, and after pipe fitting is heated to bending temperature, again mend dress cold conditions core with the tube intracavity space occurred after filling hot core sedimentation, thus guarantee that the filler of tube intracavity can provide enough supports for tube wall in bending process process, make pipe fitting distorting transformation can not occur in bending process process.

The object of the present invention is achieved like this: a kind of heavy caliber thick wall pipe fitting hot bending forming technique vulcanizing sand loading core, to be loaded by cold conditions and hot benefit sand loading core is that tube wall provides support, and for being guaranteed to realize the function of core by the auxiliary mould being bent pipe fitting and add necessity.The a whole set of tool structure of this technology comprises treats bend pipe, upper sealing plate, hoisting flange, hanger ring, upper sealing plate pressing plate, lower shrouding, core and vertical (well formula) heater.Detailed technology method is as follows: cold conditions is treated bend pipe is vertically placed and seals mouth at the bottom of pipe fitting with lower shrouding, then cold conditions core little for the cubic expansion coefficient is inserted inside pipe fitting cavity until be full of; The cold conditions filling core is treated that bend pipe is put into vertical or well formula heater and is heated to bending temperature; After having heated, by core (now for the hot) tamping of initially loading, and again add and fill out cold conditions core by inside pipe fitting cavity and fill up; Utilize upper sealing plate and upper sealing plate pressing plate to be sealed by pipe fitting top mouth, guarantee the core of twice filling by shutoff densely in pipe internal cavity, now pipe planted agent is filled up by core completely, does not have large space between tube wall and core; To treat that bend pipe hangs onto on mould, and start to carry out the processing of curved pressure with press.Owing to being had abundant inner stuffing by the tube intracavity of curved pressure pipe section, effective support can be provided for the tube wall of this pipeline section, therefore greatly can eliminate the state that is crushed of this pipeline section, guarantee that the ovality of this pipeline section caliber is qualified.

The present invention compared to existing technology tool has the following advantages: this technology is applicable to the hot bending processing and forming to heavy caliber thick wall pipe fitting; The requirement to die size and press tonnage can be reduced at hot lower processing pipe fitting, thus effectively reduce process costs and operating risk; Load core by twice and guarantee that tube intracavity has abundant filler, make pipe fitting can be obtained effectively supporting to guarantee that the ovality of this pipeline section caliber meets the requirements by curved pressure pipe section, thus substantially increase the success rate that pipe fitting bends.

Accompanying drawing explanation

Fig. 1 is pipe fitting Process Unit structure chart of the present invention.

Fig. 2 is pipe fitting of the present invention and Process Unit profile.

Fig. 3 is pipe heating process schematic representation of the present invention.

Detailed description of the invention

Below in conjunction with the drawings and specific embodiments, the present invention is further illustrated.

See Fig. 1, Fig. 2 and Fig. 3, a kind of heavy caliber thick wall pipe fitting hot bending forming technique vulcanizing sand loading core, by loading abundant filler for twice to support the curved compressive strain of tube wall respectively under cold conditions and hot two kinds of environment in tube intracavity.A whole set of tool structure comprises treats bend pipe 1, upper sealing plate 2, hoisting flange 3, hanger ring 4, upper sealing plate pressing plate 5, lower shrouding 6, initial cold conditions core 7, and vertical (well formula) heater 8, hot core 9 and hot benefit fill out cold conditions core 10.Detailed operating process is as follows: first will treat that bend pipe 1 one end is set to bottom, and the hoisting flange 3 that is welded thereon, hanger ring 4 and lower shrouding 6, lower shrouding is utilized to treat that the bottom mouth of pipe of bend pipe 1 seals, then will treat that bend pipe 1 is erected in the special groove of operating platform (or other operation frocks), and will treat that the bottom of bend pipe 1 is placed in the lower end of operating platform.Treating top mouth of pipe section welding equipment hoisting flange 3 and the hanger ring 4 of bend pipe 1, and cutting out inserting plate hole on the mouth of pipe section tube wall of top.Secondly in pipe fitting, the less initial cold conditions core 7 of the cubic expansion coefficient is loaded when treating that bend pipe 1 keeps vertical, until tube intracavity is filled up completely by core.After core filling, to treat that bend pipe 1 is vertically put into vertical (well formula) heater 8 and heated, take out to the bending technique temperature set, should guarantee that the pipe segment structure of tubular top hoisting flange 3 and hanger ring more than 4 is positioned at the outer and coated insulation blanket of heater, to guarantee that this part pipeline section does not have excessive heat expansion distortion in the heating period.After having heated, insulation blanket is removed, and apply other instruments hot core 9 is carried out tamping, make it fill the gap produced due to heat expansion distortion of tube wall.Backward pipe fitting in add hot benefit fill out cold conditions core 10 until inner chamber is filled up again.After completing filling, in pipe, put into upper sealing plate pressing plate 5, afterwards upper sealing plate pressing plate 5 is compressed by upper sealing plate 2 quick insertion inserting plate hole.Finally treat that bend pipe 1 hangs in bending mould and sends into press carry out bending process by what be disposed.

The present invention is highly suitable for bending heavy caliber thick wall pipe fitting, and tool structure is simple, and operating process is clear.Apply the cost that this technology not only can reduce pipe fitting bending technique, reduce operating risk, effectively can also solve pipe fitting and press through pipe fitting bending section distorting transformation common in journey (tube wall be crushed or caliber ovality overproof) problem curved, significantly can promote the success rate that pipe fitting bends.

Claims

1. vulcanize the large-sized heavy-wall tube hot bending forming technique of sand loading core for one kind, it is characterized in that: pipe fitting cold conditions before bending fills the little core of the cubic expansion coefficient, then be heated hot bending temperature, then benefit fills such core in pipe, and hot pipe fitting is bent under the state being full of core.

2. the pipe fitting vulcanizing sand loading core according to claim 1 bends technology, it is characterized in that: having filled the pipe heating to be curved of core during cold conditions to bending temperature in vertical or well formula heater, allow the downward sedimentation with pipe fitting expanded by heating of core upper surface, make pipe fitting upper end presentation space, in order to mend sand loading core.

3. the pipe fitting vulcanizing sand loading core according to claim 1 bends technology, it is characterized in that: at the hot lower core of dress normal-temperature of mending of pipe fitting until again filled up by tube intracavity, and with closing plate device by core compacting and shutoff upper orifice.

4. the pipe fitting vulcanizing sand loading core according to claim 1 bends technology, it is characterized in that: pipe fitting upper orifice end is provided with inserting plate hole and the upper sealing plate pressing plate for fast flashboard, and handled easily personnel carry out operation under the hot environment of pipe fitting.