JPS5857253B2 - How to line odd-shaped materials - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The disclosed technique belongs to a technique in which an inner tube for lining is inserted into the inner surface of a deformed tube, etc., and the tube is expanded and tightly fastened to be internalized.

Therefore, the present invention relates to a lining method in which a lining material such as a corrosion-resistant stainless steel material is attached and tightly fixed to a predetermined closed inner peripheral surface of a deformed material such as a deformed pipe such as a joint bellows pipe. , in particular, applying a relative temperature difference between the profiled member and the inner tube independently of each other to close the opposing gap and inserting a lined inner tube;
After inserting the lining inner tube, the above-mentioned temperature difference is applied and the opposing gap is widened, and then an expansion force is applied to the inner tube by hydraulic pressure etc. to plastically expand the tube, and then the opposite of the above is applied. This invention relates to an internal tensioning method for a profiled material in which temperature is applied to securely tighten the inner tube in the inner circumferential direction of the profiled material.

As is well known, fluid transport piping, such as plant piping, oil country tubular goods, and heat exchanger piping, may transport corrosive fluids, so not only pressure resistance but also corrosion resistance is important in the design. It is said that

Therefore, in this type of piping, its pressure resistance and corrosion resistance are determined by the pipe body.
It is necessary to securely hold not only the crotch portion, but also the portions that are joined to irregularly shaped pipe portions such as so-called oil country tubular goods, tubing, bellows, and bent portions, and to irregularly shaped members such as flanges and panels.

However, if the flow conditions of the corrosive fluid vary in temperature, pressure, chemical composition, etc., stress concentration, shear, buckling, and fatigue may occur due to the difference in thermal expansion coefficient between the inner and outer outer tubes, joint panels, etc. In order to minimize troubles such as breakage, it is desirable to have as large an interference as possible so that they can be tightened and behave as one.

By the way, shrink fitting and hydraulic pipe expansion have generally been used as means for fitting a lining material to the inner surface of a certain member, but the former uses a temperature difference, so it is difficult to fit the lining material to the inner surface of a member. This method has the disadvantage that only a gap can be obtained and it cannot be applied to irregularly shaped pipes such as bent pipes, bellows, and oil country tubular goods.

In addition, in the latter case, for example, if the yield stress of a deformed pipe is lower than that of an inner pipe, the interference will be negative, and therefore, even if the pipe is expanded, it will not be possible to connect, and the material combination,
The problem was that there were restrictions on selection, etc.

The purpose of the present invention is to solve the above-mentioned problem of attaching and fixing a tube body to a profiled material, and to solve the problem by heating the former or heating the inner tube independently of each other in any process before or after inserting the attached inner tube into the profile. Alternatively, by making them accompany each other, an insertion opposing gap is interposed in the setting, and after that, a tube expansion force is applied to the set inner tube to integrally expand the profiled material to a set degree, and then the tube expansion force is released and the tube is contracted. An excellent deformed material that allows the heating of the deformed material to be cooled and the inner tube to be heated so that the diameters of the two essentially overlap so that they can be reliably joined together. The purpose of this paper is to provide a method for lining the lining.

Next, embodiments of the present invention in accordance with the above object will be described below with reference to the drawings.

First, in the embodiment shown in Figs. 1 to 4, the lining of the bend of a double pipe is shown. Inner pipe for lining 2
is inserted based on the relationship between the inner diameter Do of the former and the outer diameter D i (Do>D i ) of the latter as shown in FIG. bend into a shape.

In this embodiment, a coil heater is appropriately wound around the outer peripheral surface of the outer tube 1 to heat the inner tube 2, and cold water or the like is allowed to flow through the inner tube 2 through an appropriate mechanism to cool the inner tube 2. As shown in the figure, the respective initial diameters Do and Di are expanded and contracted to Doh and Dic.

After changing the diameter in this way, heating and cooling are stopped, and when the cold water in the inner tube 2 is pressurized and the tube expansion force F is applied as shown in FIG. 3, the inner tube 1 is first expanded and the The stress shown in Figure 4,
Draw curves A, C, and C according to the distortion curve, and the pipe diameter is outer pipe 1.
When it reaches the inner diameter Doh of
, C′ curve.

When the tube diameter reaches the set diameter DB, the tube expansion force F is released, and the outer tube 1 contracts from C' to 2', and the inner tube 2 contracts from C to C.

Therefore, in that state, that is, the diameter of the outer pipe at point 2' is smaller than the diameter of the inner tube at point 2, and as long as that is the case, the tight clamping force will act, but the cold water in the residual cold state will be drawn from inside the inner tube 2. When the liquid is removed and water is jetted onto the outer circumferential surface of the outer tube 1 through a spray winding (not shown), the inner tube 2 is heated by the liquid removal, and conversely, the outer tube 1 is wetted with liquid and cooled.

Therefore, the inner tube 2 expands from 2 to E and increases in diameter to Di', while the outer tube 1 contracts and decreases in diameter from 2' to E' to Do', and as a result, the difference in diameter between the two tubes is Di'-Do'-AD becomes extremely large, the bend is securely tightened, and the lining is completed.

In the above embodiment, the outer tube 1 was heated and the inner tube 2 was cooled after insertion, but it is of course possible to heat the outer tube 1 and cool the inner tube 2 before insertion, or to perform either heating or cooling. It can also be applied when the yield point of the outer tube is lower than that of the inner tube, and the tube expansion force,
Heating and cooling means are subject to design changes.

Next, the embodiment shown in Figs. 5 and 6 is a bellows embodiment for an expansion joint, and a bellows deformed member 1' which is integrally welded between the flanges 3 and 3 in a predetermined manner is As shown in Fig. 5, the inner tube 2' for lining is inserted, and the diameter is increased through the outer tube heating and inner tube cooling processes as in the previous example.
The diameter is reduced, and hydraulic pressure is applied to the inside of the inner tube 2' to expand the tube and strain it using the difference in yield stress.The expansion force is released at the set strain, the tube is contracted, and again, contrary to the aforementioned thermal effect, the tube is expanded. As in the example, increase the temperature and diameter of the inner tube,
The diameter of the outer tube is reduced by cooling, the relative diameter difference is increased, and the joint surfaces are tightly tightened to securely line the inner tube as shown in FIG.

In addition, in this embodiment, as in the previous embodiment, the bellows outer tube 1
The selection of heating and cooling processes before and after insertion of the inner tube 2' into the inner tube 2', the adoption of only one of them, the selection of cooling heating after the tube expansion force is released, and the selection of heating and cooling processes before tube expansion. The combinations and the like are free, and this does not preclude all of the embodiments.

Of course, it is also applicable to cases where the yield point of the bellows outer tube is lower than that of the inner tube.

The embodiment shown in FIGS. 7 and 8 is an embodiment of oil country tubing, and as shown in FIG. Insert the tube, heat the outer tube, cool the inner tube, expand the tube after a relative diameter change, and after releasing the expansion force, cool the outer tube and increase the temperature of the inner tube. overlap the tightening allowance due to
As shown in FIG. 8, the tension is securely tightened.

Thereafter, the threaded joint 4 is processed appropriately.

In this embodiment, a stepped portion of the tubing is formed on the inner surface 5, but extremely large tightening is required to expand the relative diameter difference through the thermal deformation strain, tube expansion strain, and further thermal deformation. A certain amount of clearance is obtained, and the tightening and fixation are reliably performed.

Incidentally, similar to the bellows mode described above, when cooling and heating functions are used together, it is extremely effective when used both before and after pipe expansion.

In the embodiment shown in FIGS. 9 and 10, a pipe 2" is joined to a tube plate 1" as a deformed member of an isothermal heat exchanger for a nuclear reactor, and a pipe 2" is used as a kind of lining at a joint 6. This is an embodiment in which the pipes 2''' The joint part of the pipe is cooled to a set temperature and smoothly inserted into the joint part 6 of the tube plate 1'' at natural temperature, and then an expansion force F is applied by hydraulic pressure pipe expansion to increase the diameter of the pipe 2''. , the pipe is brought into contact with the joint 6, the pipe is further expanded, compressive stress is applied to the tube sheet 1'' to increase its inner diameter, and after the set strain is formed, the tube expansion force F is released to compress both, and the pipe 2'' is By increasing the diameter, the relative minus diameter difference is expanded, and the inner lining can be reliably tightened and fixed.

In this embodiment, it is of course possible to heat the tube plate 1'' by inserting it, expand it, and then cool it, and the effect in that case is further enhanced.

It goes without saying that the embodiments of the present invention are not limited to the above-mentioned embodiments, and various types of lining equipment and piping are possible, including heating, cooling, and expanding pipes.

As described above, according to the present invention, a lining material is attached and fixed to the closed inner circumferential surface of a helical member such as an oil pipe bend, a telescopic pipe bellows, an oil country tubular tubing, a heat exchanger tube sheet joint, etc. In the method, before or after inserting the lined inner tube into the closed inner circumferential surface, selectively heating the profiled material and cooling the lined inner tube independently, and then By expanding the inner tube plastically and forming a strain shape integrally with the deformed material to release the expansion force, the deformed material shrinks negatively relative to the inner tube when the inner pipe contracts. In addition to being able to form a diameter and initially forming a sufficient interference margin, we have also made it possible to independently thermally contract and expand the post-contraction shaped material and the inner tube. Secondary relative negative diameter reduction is taken into account, and therefore, sufficient interference is formed for the above-mentioned irregularly shaped materials, where it is difficult to obtain a tight joint compared to general joints such as double pipes. Also, an excellent effect is achieved in that tight fastening can be performed reliably.

Furthermore, according to the present invention, even in the case of a combination in which the yield point of the profiled material is lower than that of the lining inner pipe, tightening and fixing can be performed reliably in the settings, so that there is no need to worry about the selection of equipment piping and constituent materials. is eliminated, so each profile is lined and the working pressure,
It has an excellent effect of not causing buckling, fatigue failure, etc. even under high temperature and corrosive fluid operation.

Furthermore, this can be done before and after pipe expansion depending on the heating temperature and cooling conditions, which has the advantage of greatly increasing the degree of freedom in joining conditions.

In addition, there is the advantage that the work is easier because the gap between the joints can be freely created when inserting the inner tube.

[Brief explanation of the drawing]

The drawings show embodiments of the invention, and include sections 1.2.
Fig. 3 is an explanatory diagram of the lining process of one embodiment, Fig. 4 is an explanatory diagram of the relationship between the diameter of the inner and outer tubes and stress, Fig. 5.6 is an explanatory diagram of the lining process of another embodiment, and Fig. 7.8 is an explanatory diagram of the lining process of another embodiment. FIGS. 9 and 10 are explanatory views of the lining process of another embodiment, and are explanatory views of the outer lining process. 1.1', 1", 1///... deformed material, 2.2
1.2I//, 2/u... Lining material.

Claims (1)

[Claims] 1 In a lining method in which a lining material is attached and fixed to the closed inner peripheral surface of a deformed material, an inner tube of the lining material is inserted into the closed inner peripheral surface of the deformed material, and the deformed material is attached either before or after the lining material is inserted into the closed inner peripheral surface of the deformed material. A relative temperature difference is created between the material and the inner tube to create a gap between them, and a tube expansion force is applied to the inside of the inserted inner tube to plastically expand the inner tube and bring it into close contact with the closed inner circumferential surface of the deformed material. A method for lining a deformed material, characterized in that after the deformed material and the inner tube are heated, a relative temperature difference opposite to that described above is applied to the deformed material and the inner tube, and the deformed material and the inner tube are tightly fastened and lined. .