CN117921255A - Preheating process structure before welding of pipe welded junction - Google Patents

Abstract

The invention relates to the field of pipeline welding preheating, in particular to a preheating process structure before welding a welded junction of a pipeline. The preheating process structure before welding of the pipe weld junction comprises two groups of closed flame heaters, wherein the two groups of closed flame heaters are assembled on pipes on two sides of the weld junction, an external pipe butt joint device is assembled at the weld junction, the external pipe butt joint device is positioned between the two groups of closed flame heaters, and the closed flame heaters are respectively connected with a combustible gas supply system. The advantages are that: the structure design is simple and reasonable, and the purpose that the welding junction heating and the welder welding are carried out simultaneously can be realized.

Description

Preheating process structure before welding of pipe welded junction

Technical Field

The invention relates to the field of pipeline welding preheating, in particular to a preheating process structure before welding a welded junction of a pipeline.

Background

When the oil and gas pipeline is subjected to fire maintenance, preheating before welding of a fire welding port and preheating before welding of repairing and welding of the fire welding port are needed, so that the effective completion rate of fire welding in severe cold, especially in northeast China is ensured.

In general, pipe orifice welding for repair and repair of pipelines lasts for a plurality of hours, and an orifice heater is arranged to maintain constant the welding temperature of a welded junction and the interlayer temperature during welding by converting electric energy into heat energy. The welding port of the current long-distance pipeline is preheated by adopting a pipeline welding flame heater, but the welding port needs to be continuously heated in the welding process, so that the existence of the pipeline welding flame heater occupies the welding operation space of a welder, and the welding operation is in conflict.

Along with the higher and higher time efficiency requirement of oil and gas pipeline maintenance repair and the complexity of the pipeline maintenance repair real environment, the manual operation mode that the movement of the pipeline welding flame heater along the fixed track welded junction influences welding and hinge fixing is low in efficiency, and the practical requirement cannot be met.

Based on this, a new preheating process structure before welding of the welded junction needs to be developed to meet the requirement of simultaneous welding and preheating of the welded junction.

Disclosure of Invention

The invention aims to solve the technical problem of providing a preheating process structure before welding of a pipe weld joint, and effectively overcomes the defects of the prior art.

The technical scheme for solving the technical problems is as follows:

The preheating process structure before welding the welded junction of the pipeline comprises two groups of closed flame heaters, wherein the two groups of closed flame heaters are assembled on the pipeline on two sides of the welded junction, an external pipeline butt joint device is assembled at the welded junction, the external pipeline butt joint device is positioned between the two groups of closed flame heaters, and the closed flame heaters are respectively connected with a combustible gas supply system.

On the basis of the technical scheme, the invention can be improved as follows.

Further, the closed flame heater includes a pair of semicircular heating chambers, one ends of the pair of heating chambers are hinged, the other ends of the pair of heating chambers are detachably connected through a connecting piece, the heating chambers are provided with semicircular air inlet chambers and combustion chambers from outside to inside, the inner sides of the combustion chambers are provided with air nozzles penetrating through the air inlet chambers and the combustion chambers, the heating chambers are provided with air inlets communicated with the air inlet chambers, the heating chambers are provided with air vents and air outlets communicated with the combustion chambers, and the combustible gas supply system is connected with the air inlets through pipelines respectively.

Further, the air inlet is connected with an air inlet nozzle, and an air inlet valve is arranged on the air inlet nozzle.

Further, the air inlet and the air outlet are arranged at one end of the heating bin, and the air vent is arranged at the other end of the heating bin.

Further, the ventilation openings are provided in plurality and are circumferentially arranged at a position corresponding to the combustion chamber at one end of the heating chamber, and the exhaust openings are arranged at a position corresponding to the combustion chamber at the other end of the heating chamber.

Further, a flue communicated with the exhaust port is arranged at the other end of the heating bin, and the flue extends along the radial direction of the heating bin.

Further, the combustible gas supply system comprises a liquefied gas tank, a gas supply main pipe, two first-stage gas supply branch pipes and four second-stage gas supply branch pipes, wherein one end of the gas supply main pipe is connected with a gas outlet of the liquefied gas tank, one end of the two first-stage gas supply branch pipes is respectively connected with the other end of the gas supply main pipe, four second-stage gas supply branch pipes are equally divided into two groups, the two second-stage gas supply branch pipes of each group are respectively connected with the other ends of the two first-stage gas supply branch pipes, the four second-stage gas supply branch pipes are respectively connected with gas inlets of the four heating cabins in a one-to-one correspondence manner, and a pressure reducing valve is arranged on the gas supply main pipe.

Further, one end of the pair of heating bins is hinged through a hinge.

Further, the connecting piece comprises a bolt, the other ends of the pair of heating bins are provided with connecting plates which are mutually abutted, and the connecting piece penetrates through the connecting plates and is fixedly connected through nuts.

Further, a semicircular airflow channel is arranged in the air inlet chamber corresponding to the air nozzle, the air inlet is communicated with the airflow channel through a pipeline, and a heat preservation and insulation layer is filled outside the airflow channel.

The beneficial effects of the invention are as follows: the structure design is simple and reasonable, the purpose that the welding mouth heating and the welder welding are carried out simultaneously can be realized, and the welding period is effectively shortened.

Drawings

FIG. 1 is an assembled view of the structure of the pre-weld preheating process of the present invention for pipe weld;

FIG. 2 is a cross-sectional view of a pre-weld preheating process configuration for pipe weld of the present invention;

FIG. 3 is a cross-sectional view of a pre-weld preheating process structure for pipe weld of the present invention assembled for use on a pipe;

Fig. 4 is a schematic diagram of a combustible gas supply system in a preheating process structure before welding a pipe weld.

In the drawings, the list of components represented by the various numbers is as follows:

1. Closed flame heater; 2. an external pipe butt joint device; 11. a heating bin; 12. a connecting piece; 111. an intake chamber; 112. a combustion chamber; 113. an air flow channel; 114. a heat preservation and insulation layer; 121. a liquefied gas tank; 122. a main air supply pipe; 123. a primary air supply branch pipe; 124. a secondary air supply branch pipe; 1111. an air inlet; 1112. a vent; 1113. an exhaust port; 1114. an air inlet nozzle; 1115. an air inlet valve; 1116. a flue; 1221. a pressure reducing valve.

Detailed Description

The principles and features of the present invention are described below with reference to the drawings, the examples are illustrated for the purpose of illustrating the invention and are not to be construed as limiting the scope of the invention.

Examples: as shown in fig. 1 to 3, the preheating process structure before welding the pipe weld junction in this embodiment includes two groups of closed type flame heaters 1, the two groups of closed type flame heaters 1 are assembled on the pipes on both sides of the weld junction, the pipe outer butt joint device 2 is assembled at the weld junction, the pipe outer butt joint device 2 is positioned between the two groups of closed type flame heaters 1, and the closed type flame heaters 1 are respectively connected with a combustible gas supply system.

The use process is as follows:

The welding seam of the pipeline is welded by a butt-welding device 2 (which is a product in the prior art and is not described in detail herein) outside the pipeline, a group of closed type flame heaters 1 are additionally arranged on two sides of the butt-welding device 2 outside the pipeline, the combustible gas required by heating the closed type flame heaters 1 is supplied by a combustible gas supply system, and the two groups of closed type flame heaters 1 heat flames on two sides of the pipe to reach interlayer temperature required by welding. Then welding is carried out, in the welding process, the closed type flame heater 1 can not cause obstruction to welding, and meanwhile, the interlayer temperature in the welding process can be effectively ensured. The whole device has simple and reasonable structural design, and can realize the purpose of simultaneous weld junction heating and welder welding.

In a preferred embodiment, the sealed type fired heater 1 includes a pair of semicircular heating chambers 11, one ends of the pair of heating chambers 11 are hinged, the other ends are detachably connected by a connector 12, an air inlet chamber 111 and a combustion chamber 112 are provided in the heating chambers 11 in a semicircular shape from outside to inside, an air nozzle penetrating the air inlet chamber 111 and the combustion chamber 112 is provided between the air inlet chamber 111 and the combustion chamber 112, the heating chambers 11 are provided with an air inlet 1111 communicating with the air inlet chamber 111, the heating chambers 11 are provided with an air vent 1112 and an air outlet 1113 communicating with the combustion chamber 112, and the combustible gas supply system is connected with the air inlet 1111 by pipelines, respectively.

In the above embodiment, the pair of heating chambers 11 are surrounded on the pipe when assembled, then the other ends of the pair of heating chambers 11 are assembled and fixed through the connecting piece 12, so that the pair of heating chambers 11 are firmly assembled on the pipe, then the air inlet 1111 is connected with the combustible gas supply system, the combustible gas is introduced into the combustion chamber 112 through the air inlet chamber 111, and simultaneously, the combustion process is ignited through any one of the ventilation openings 1112, the ventilation openings 1112 continuously supply air and oxygen, and the flue gas generated by combustion is discharged through the air outlet 1113, so that the overall structural design is simple and reasonable.

As a preferred embodiment, the air inlet 1111 is connected to an air inlet nozzle 1114, and the air inlet nozzle 1114 is provided with an air inlet valve 1115.

In the above embodiment, the inlet valve 1115 is used to control the inlet flow of the combustible gas, so as to control the flame size and achieve the purpose of regulating the preheating temperature.

In a preferred embodiment, the air inlet 1111 and the air outlet 1113 are provided at one end of the heating chamber 11, and the air vent 1112 is provided at the other end of the heating chamber 11.

In the above embodiment, in use, the air inlet 1111 and the air outlet 1113 of the two groups of closed fired heaters 1 are disposed at the ends of the two groups of closed fired heaters far from each other, and the air vent 1112 is disposed at the ends of the two groups of closed fired heaters close to each other, so that the design is reasonable, the welding position between the two groups of closed fired heaters is large, and the operation is easy.

In a preferred embodiment, the plurality of ventilation openings 1112 are provided at a position corresponding to the combustion chamber 112 at one end of the heating chamber 11 in the circumferential direction, and the exhaust opening 1113 is provided at a position corresponding to the combustion chamber 112 at the other end of the heating chamber 11.

In the above embodiment, the ventilation openings 1112 are designed in a plurality and distributed along the circumferential direction, so that the outside air can be maximally ensured to enter the combustion chamber 112, and the combustion stability can be ensured. The exhaust ports 1113 may be one, and the exhaust ports 1113 may be located near the other ends of the two heating chambers 11 and at the upper portion of the pipe during the assembly process.

In a preferred embodiment, a flue 1116 communicating with the exhaust port 1113 is provided at the other end of the heating chamber 11, and the flue 1116 extends along the radial direction of the heating chamber 11.

In the above embodiment, the radially outward end of the flue 1116 is provided as a flue opening, and the inward end is in communication with the exhaust 1113, and the combusted flue gas can be effectively exhausted through the flue 1116.

As a preferred embodiment, as shown in fig. 4, the combustible gas supply system includes a liquefied gas tank 121, a gas supply main pipe 122, two primary gas supply branch pipes 123 and four secondary gas supply branch pipes 124, one end of the gas supply main pipe 122 is connected to a gas outlet of the liquefied gas tank 121, one end of the primary gas supply branch pipe 123 is respectively connected to the other end of the gas supply main pipe 122, four secondary gas supply branch pipes 124 are equally divided into two groups, two secondary gas supply branch pipes 124 of each group are respectively connected to the other ends of the primary gas supply branch pipes 123, four secondary gas supply branch pipes 124 are respectively connected to gas inlets 1111 of the four heating chambers 11 in one-to-one correspondence, and a pressure reducing valve 1221 is provided on the gas supply main pipe 122.

In the above embodiment, after the pressure of the liquefied gas in the liquefied gas tank 121 is reduced by the pressure reducing valve 1221, the liquefied gas enters the two primary air supply branch pipes 123, then enters the four secondary air supply branch pipes 124, finally enters the four heating chambers 11 of the two groups of closed type flame heaters 1 through the air inlets 1111, and is delivered to the combustion chamber 112 for combustion.

In this embodiment, the other end of the air supply main pipe 122 is connected with one end plug bush of two first-stage air supply branch pipes 123 through a tee joint, the buckle is arranged at the position where the plug bush is connected to stabilize, the other ends of the two first-stage air supply branch pipes 123 are respectively connected with one end plug bush of four second-stage air supply branch pipes 124 through the tee joint, the position where the plug bush is connected is likewise stabilized through the buckle, the other ends of the four second-stage air supply branch pipes 124 are connected with the corresponding air inlet 1111 plug bush, and the position where the plug bush is connected is also stabilized through the buckle.

In this embodiment, one end of the pair of heating chambers 11 is hinged by a hinge.

In a preferred embodiment, the connecting members 12 include bolts, the other ends of the pair of heating chambers 11 are provided with connecting plates which are abutted against each other, and the connecting members 12 are passed through the connecting plates and are fixed by nuts.

In the above embodiment, after the pair of heating chambers 11 embraces the pipe, bolts pass through the connecting plates at the other ends of the heating chambers, and nuts are mounted for fastening.

In a preferred embodiment, a semicircular airflow channel 113 is provided in the intake chamber 111 at a position corresponding to the air nozzle, the air inlet 1111 is connected to the airflow channel 113 through a pipeline, and a heat insulating layer 114 is filled outside the airflow channel 113.

In the above embodiment, a plurality of air nozzles are formed on the side wall of the air inlet chamber 111 connected to the combustion chamber 112 at intervals in the circumferential direction, and at the same time, an air flow channel 113 is formed on the side wall of the air inlet chamber 111 connected to the combustion chamber 112 and is connected to the air nozzles, and the combustible gas enters the air flow channel 113 through the air inlet 1111 and the pipeline, and then is sprayed to the combustion chamber 112 from each air nozzle, and then is ignited for combustion. The heat preservation and insulation layer 114 is filled outside the airflow channel 113 (i.e. in most of the air inlet chamber 111) to insulate heat, so that heat loss is reduced.

In this embodiment, the thermal insulation layer 114 may be conventional thermal insulation cotton.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present invention, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

While embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the invention, and that variations, modifications, alternatives and variations may be made to the above embodiments by one of ordinary skill in the art within the scope of the invention.

Claims (10)

1. The preheating process structure before welding of the welded junction of the pipeline is characterized in that: the gas-fired furnace comprises two groups of closed flame heaters (1), wherein the two groups of closed flame heaters (1) are assembled on pipelines on two sides of a welded junction, an outer butt joint device (2) is assembled at the welded junction, the outer butt joint device (2) is positioned between the two groups of closed flame heaters (1), and the closed flame heaters (1) are respectively connected with a combustible gas supply system.

2. The pre-weld preheating process structure for pipe weld according to claim 1, wherein: the closed flame heater (1) comprises a pair of semicircular heating bins (11), one ends of the pair of heating bins (11) are hinged, the other ends of the pair of heating bins (11) are detachably connected through a connecting piece (12), an semicircular air inlet chamber (111) and a combustion chamber (112) are arranged in the heating bins (11) from outside to inside, an inner opening of the combustion chamber (112) is arranged, an air jet penetrating through the air inlet chamber (111) and the combustion chamber (112) is arranged between the air inlet chamber and the combustion chamber (112), the heating bins (11) are provided with air inlets (1111) communicated with the air inlet chamber (111), the heating bins (11) are provided with air vents (1112) and air outlets (1113) communicated with the combustion chamber (112), and the combustible gas supply system is connected with the air inlets (1111) through pipelines respectively.

3. The pre-weld preheating process structure for pipe weld according to claim 2, wherein: the air inlet (1111) is connected with an air inlet nozzle (1114), and an air inlet valve (1115) is arranged on the air inlet nozzle (1114).

4. The pre-weld preheating process structure for pipe weld according to claim 2, wherein: the air inlet (1111) and the air outlet (1113) are arranged at one end of the heating bin (11), and the ventilation opening (1112) is arranged at the other end of the heating bin (11).

5. The pre-weld preheating process structure for pipe weld according to claim 4, wherein: the ventilation openings (1112) are arranged in a plurality, are circumferentially arranged at the part of one end of the heating bin (11) corresponding to the combustion chamber (112), and the exhaust openings (1113) are arranged at the part of the other end of the heating bin (11) corresponding to the combustion chamber (112).

6. The pre-weld preheating process structure for pipe weld according to claim 5, wherein: the other end of the heating bin (11) is provided with a flue (1116) communicated with the exhaust port (1113), and the flue (1116) extends along the radial direction of the heating bin (11).

7. The pre-weld preheating process structure for pipe weld according to claim 2, wherein: the combustible gas supply system comprises a liquefied gas tank (121), a gas supply main pipe (122), two primary gas supply branch pipes (123) and four secondary gas supply branch pipes (124), one end of the gas supply main pipe (122) is connected with a gas outlet of the liquefied gas tank (121), one end of each primary gas supply branch pipe (123) is respectively connected with the other end of the gas supply main pipe (122), four secondary gas supply branch pipes (124) are equally divided into two groups, two secondary gas supply branch pipes (124) of each group are respectively connected with the other ends of the primary gas supply branch pipes (123), four secondary gas supply branch pipes (124) are respectively connected with gas inlets (1111) of four heating bins (11) in one-to-one correspondence, and a pressure reducing valve (1221) is arranged on the gas supply main pipe (122).

8. The pre-weld preheating process structure for pipe weld according to claim 2, wherein: one end of the pair of heating bins (11) is hinged through a hinge.

9. The pre-weld preheating process structure for pipe weld according to claim 2, wherein: the connecting pieces (12) comprise bolts, the other ends of the pair of heating bins (11) are provided with connecting plates which are mutually abutted, and the connecting pieces (12) penetrate through the connecting plates and are fixedly connected through nuts.

10. A pre-weld preheating process according to any of claims 2 to 9, wherein: the position in the air inlet chamber (111) corresponding to the air jet is provided with a semicircular air flow channel (113), the air inlet (1111) is communicated with the air flow channel (113) through a pipeline, and a heat preservation and insulation layer (114) is filled outside the air flow channel (113).