CN-122015535-A - High-pressure-resistant heat exchanger and welding method thereof

CN122015535ACN 122015535 ACN122015535 ACN 122015535ACN-122015535-A

Abstract

The invention belongs to the technical field of heat exchange equipment, and particularly relates to a high-pressure-resistant heat exchanger and a welding method thereof, wherein the heat exchanger comprises a gradient wall thickness shell, a reinforcing rib shell, a tube plate, a drop type tube side channel and a temperature-pressure self-adaptive integrated ring, a composite pressure-bearing structure is arranged on the outer wall of the drop type tube side channel, the reinforcing rib shell is provided with a cold source and a heat source pipeline, and an anti-freezing and blocking structure is arranged between the gradient wall thickness shell and the drop type tube side channel; the welding method ensures the connection reliability of each part through layering, staged accurate welding and stress control, and further strengthens the high pressure resistance of the equipment.

Inventors

XU LINHUI
ZHANG JIE
ZHU CHAO

Assignees

四川奥菲尔科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260319

Claims (8)

1. A high-pressure resistant heat exchanger is characterized by comprising a gradient wall thickness shell, reinforcing rib end covers detachably connected with two ends of the gradient wall thickness shell, a tube plate arranged in the gradient wall thickness shell and matched with the corresponding reinforcing rib end covers for blocking, a drop type tube pass channel arranged on the tube plate, a temperature-pressure self-adaptive integrated ring arranged between the reinforcing rib end covers and the gradient wall thickness shell, wherein the outer wall of the drop type tube pass channel is provided with a composite pressure bearing structure, the composite pressure bearing structure comprises an axial inner rib, a variable rigidity supporting unit, a self-adaptive pressure releasing unit and a spiral baffle plate, a cold source inlet tube and a cold source outlet tube for cold source flow are respectively arranged at the top and the bottom of the reinforcing rib end covers at two sides, a heat source inlet tube and a heat source outlet tube for heat source flow are further arranged at the top and the bottom between the reinforcing rib end covers and the temperature-pressure self-adaptive integrated ring, and an anti-freezing blocking structure is further arranged between the gradient wall thickness shell and the drop type tube pass channel.
2. A heat exchanger resistant to high pressure as set forth in claim 1, wherein the wall thickness of the gradient wall thickness housing is linearly decreased from both ends to the middle area, annular grooves are uniformly distributed on the inner wall of the gradient wall thickness housing along the circumferential direction, and elastic gaskets and temperature sensors are arranged in the annular grooves.
3. The heat exchanger of claim 1, wherein the tube plate comprises a base layer, a stress buffer layer and a corrosion resistant layer which are sequentially connected, a plurality of interfaces are arranged on the tube plate, wedge-shaped blocks connected with the interfaces are arranged on the reinforcing rib seal heads, and temperature sensors are arranged in the wedge-shaped blocks.
4. A heat exchanger with high pressure resistance as set forth in claim 3, wherein the temperature and pressure self-adapting integrated ring comprises an outer ring, an inner ring, a temperature and pressure compensation block and an elastic member, wherein the outer ring is fixedly connected with the gradient wall thickness shell, the inner ring is provided with a wedge-shaped inclined plane, the outer wall of the elastic member is fixedly connected with the temperature and pressure compensation block, and the temperature and pressure compensation block is fixedly clamped with the wedge-shaped inclined plane.
5. The heat exchanger of claim 1, wherein the variable stiffness support unit is a shape memory alloy tube arranged on the inner wall of the axial inner rib and wrapping the drop tube side passage, the self-adaptive pressure relief unit is a pressure relief tube arranged on the outer wall of the shape memory alloy tube, the pressure relief tube is communicated with a pressure relief valve, and the pressure relief valve is communicated with the gradient wall thickness shell.
6. The heat exchanger of claim 1, wherein the drop tube side channel comprises a horizontal section, a falling section and a heat preservation section, wherein the horizontal section, the falling section and the heat preservation section are arranged along the flow direction of the cold source, the falling section is arranged in a crossing manner, the horizontal section is communicated with the cold source inlet tube, and the end part of the heat preservation section is communicated with the cold source outlet tube.
7. The heat exchanger of claim 1, wherein the anti-freezing and blocking structure comprises an anti-freezing pipe which is arranged on the outer wall of the shape memory alloy pipe and is communicated with the heat source inlet pipe, heat conducting oil is arranged in the anti-freezing pipe, and a control valve is arranged at the communication part of the anti-freezing pipe and the heat source inlet pipe.
8. A method for welding a heat exchanger resistant to high pressure, applied to the heat exchanger resistant to high pressure as claimed in any one of claims 1 to 7, comprising the steps of: s1, layering welding of a composite pressure-bearing structure, namely pre-installing an elastic gasket and a temperature sensor in an annular groove of a gradient wall thickness shell, layering and welding an axial inner rib and an inner wall of the shell by adopting argon arc welding, determining the fitting degree by ultrasonic monitoring after backing welding of a first layer, synchronously controlling the welding temperature and the temperature sensor to link during filling welding of a second layer, and avoiding thermal deformation of the elastic gasket; S2, stress guiding welding of the tube plate and the shell, namely, after the base layer, the stress buffer layer and the corrosion-resistant layer of the tube plate are subjected to explosive composite molding, butt-jointing the tube plate and the shell with the gradient wall thickness by adopting electron beam welding, welding the outer Zhou Huanfeng of the tube plate firstly, then welding the connecting point of the tube plate and the axial inner rib, positioning the wedge-shaped block of the seal head of the reinforcing rib synchronously through the conical interface of the tube plate, and reserving an assembly gap; S3, welding and fixing an outer ring of the temperature-pressure self-adaptive integrated ring and a gradient wall thickness shell, clamping and positioning an inner ring, a temperature-pressure compensation block and an elastic piece according to wedge-shaped inclined planes, adopting laser backing welding to fix an axial gap between the inner ring and the outer ring, and finally alternately welding the outer ring and a reinforcing rib seal head along the circumferential direction, and adjusting welding current through deformation feedback of the temperature-pressure compensation block in the welding process to ensure sealing and attaching precision; S4, cooperatively welding an anti-freezing and anti-blocking structure, namely attaching an anti-freezing pipe to the outer wall of the shape memory alloy pipe according to a preset path, adopting pulsed argon arc welding to weld the anti-freezing pipe and the shape memory alloy pipe in a segmented manner, pre-installing a control valve and reserving an adjusting space when a heat source inlet pipe is welded to the communication position of the anti-freezing pipe, and then adopting brazing to seal the joint; S5, integral stress relief and sealing verification, namely placing the integral equipment in an annealing furnace for sectional stress relief annealing, monitoring the temperature of a welding area through a temperature sensor in a temperature rising stage, detecting internal defects of a welding line through ultrasonic scanning in a heat preservation stage, respectively introducing media through a cold source inlet pipe and a heat source inlet pipe after annealing, and testing the linkage tightness of a pressure relief valve and a control valve and the leakage condition of the welding line.

Description

High-pressure-resistant heat exchanger and welding method thereof Technical Field The invention belongs to the technical field of heat exchange equipment, and particularly relates to a high-pressure-resistant heat exchanger and a welding method thereof. Background The heat exchanger is used as core equipment for realizing heat transfer in industrial production, is widely applied to multiple fields of petroleum, chemical industry, energy sources, metallurgy and the like, and particularly in high-pressure working conditions (such as high-pressure hydrogenation and high-pressure heat exchange systems), and has extremely high requirements on pressure bearing capacity, sealing performance, temperature and pressure suitability and frost blocking resistance of the equipment. At present, the high-pressure resistant design of the existing heat exchanger has a plurality of defects, and is particularly analyzed by combining the prior art, the high-pressure resistant heat exchanger is disclosed in the prior art, the high-pressure resistant performance is improved through a hemispherical head, a bamboo joint bionic structure radiating pipe and an electron beam welding process, a composite pressure bearing structure is not arranged, the load is dispersed only by means of the telescopic throat of the radiating pipe, the load concentration under high-pressure working conditions is difficult to deal with, the high-temperature pressure self-adaptive adjustment and anti-freezing and blocking design is avoided, sealing failure easily occurs during temperature fluctuation, freezing and blocking easily occurs under low-temperature working conditions, the high-temperature high-pressure anti-corrosion composite heat exchanger disclosed in the prior art is further disclosed, the high-temperature high-pressure anti-corrosion composite heat exchanger is realized through composite materials and a split cylinder, the split cylinder structure is complex, the manufacturing cost is high, the temperature pressure self-adaptive structure and the anti-freezing and blocking design are also not effectively optimized, and the technical problems under the complex working conditions such as high pressure and low temperature cannot be solved. In summary, in the prior art, a heat exchanger with a certain high pressure resistance adopts a shell with uniform wall thickness and a fixed supporting structure, is difficult to adapt to dynamic changes of pressure and temperature, and lacks an effective self-adaptive pressure relief and anti-freezing protection mechanism, so that the reliability of the equipment is insufficient under extreme working conditions. Therefore, a heat exchanger structure capable of adapting to high pressure and temperature difference changes and having an anti-freezing and anti-blocking function and a corresponding reliable welding process are needed. Disclosure of Invention Aiming at the defects in the prior art, the invention aims to provide a high-pressure-resistant heat exchanger and a welding method thereof, so as to solve the problems that the existing heat exchanger is easy to deform, freeze and block and lacks self-adaptive pressure relief capability under the working conditions of high pressure and large temperature difference. The heat exchanger comprises a gradient wall thickness shell, reinforcing rib end covers detachably connected with two ends of the gradient wall thickness shell, a tube plate arranged in the gradient wall thickness shell and plugged with the corresponding reinforcing rib end covers in a matched mode, a drop tube pass channel arranged on the tube plate, a temperature-pressure self-adaptive integrated ring arranged between the reinforcing rib end covers and the gradient wall thickness shell, wherein a composite pressure-bearing structure is arranged on the outer wall of the drop tube pass channel and comprises an axial inner rib, a variable rigidity supporting unit, a self-adaptive pressure relief unit and a spiral baffle plate, cold source inlet tubes and cold source outlet tubes for cold source flow are respectively arranged at the top and the bottom of the reinforcing rib end covers, a heat source inlet tube and a heat source outlet tube for heat source flow are further arranged at the top and the bottom between the reinforcing rib end covers and the temperature-pressure self-adaptive integrated ring, and an anti-freezing and plugging structure is further arranged between the gradient wall thickness shell and the drop tube pass channel. Further, the wall thickness of the gradient wall thickness shell linearly decreases from two ends to the middle area, annular grooves are uniformly distributed on the inner wall of the gradient wall thickness shell along the circumferential direction, and an elastic gasket and a temperature sensor are arranged in the annular grooves. Further, the tube plate comprises a base layer, a stress buffer layer and a corrosion-resistant layer which are sequentially connec