Cold and hot fluid confluence flow guide pipe in reducer tee

Abstract

The invention discloses a cold and hot fluid confluence diversion pipe in a reducer tee. The cold and hot fluid confluence diversion pipe comprises the reducer tee, a first diversion straight pipe and a branch pipe, a first flow guide straight pipe is arranged in the reducing tee, and a conical shell is arranged at one end of the first flow guide straight pipe and fixedly connected with a port of the reducing tee. A first supporting block is arranged at the other end of the first flow guide straight pipe, and the branch pipe comprises a second flow guide straight pipe and a flow guide vertical pipe; the second flow guide straight pipe is arranged in the first flow guide straight pipe, and a second supporting block is arranged at one end of the second flow guide straight pipe; and the other end of the second flow guide straight pipe is fixedly connected with the flow guide vertical pipe. The interlayer is arranged between the flow guide pipe and the external conventional reducing tee, so that cold fluid can flow in, cracks on the shoulder of the outer pipe under high temperature, high pressure and high flow can be effectively avoided, the temperature field of the tee is more uniform, the service life of a pipeline is prolonged, the safety and the stability are improved, the structure is simple, and industrial production is easy.

Description

Technical Field

[0001] The invention relates to the field of industrial energy-saving pipelines, and in particular to a cold and hot fluid converging and guiding pipe in a reducing tee. Background Art

[0002] High temperature, high pressure and high flow rate are the development trends in my country and the world. At present, there is a risk of cracking of the shoulder of the tee under high temperature and high pressure, especially when the cold and hot fluids converge in the tee, which will increase the stress of the shoulder of the tee and more easily cause cracking and other problems. Therefore, in this case, most people will use heat exchangers as a substitute, but the design of high temperature and high pressure heat exchangers is more difficult, and this equipment can be a good substitute. Summary of the invention

[0003] The purpose of the present invention is to provide a hot and cold fluid converging guide pipe in a reducing tee to address the problems that the existing high-temperature, high-pressure and high-flow heat exchangers are relatively complex in design and the tee shoulders are prone to cracking.

[0004] The objective of the present invention is achieved through the following technical solutions:

[0005] A hot and cold fluid converging flow guide pipe in a reducing tee, comprising: a reducing tee, a first flow guide straight pipe and a branch pipe; the reducing tee is provided with a first flow guide straight pipe, one end of the first flow guide straight pipe is provided with a cone shell, and is fixedly connected to the port of the reducing tee; the other end of the first flow guide straight pipe is provided with a first support block, and a gap is left between the first support block and the reducing tee, so as to reserve the deformation displacement of the first flow guide straight pipe;

[0006] The branch pipe includes a second flow-guiding straight pipe and a flow-guiding vertical pipe; the second flow-guiding straight pipe is arranged in the first flow-guiding straight pipe, a second support block is arranged at one end of the second flow-guiding straight pipe, and a gap is left between the second support block and the first flow-guiding straight pipe for reserving the deformation displacement of the second flow-guiding straight pipe; the other end of the second flow-guiding straight pipe is fixedly connected to the flow-guiding vertical pipe.

[0007] Furthermore, the branch pipe includes a diversion elbow, and the second diversion straight pipe is connected to the diversion vertical pipe through the diversion elbow; the diversion elbow is used for diversion to avoid excessive thermal stress on the shoulder of the diversion pipe.

[0008] Furthermore, an orifice plate is provided at the port of the guide riser, and the orifice plate is used to inject cold fluid into the interlayer between the reducing tee and the branch pipe to play a role in liquid diversion. By injecting cold fluid, the temperature of the shoulder of the reducing tee is made uniform, thereby avoiding excessive thermal stress and preventing the shoulder of the reducing tee from cracking.

[0009] Furthermore, the number of the first support blocks is 4, and the number of the second support blocks is 4.

[0010] Furthermore, the cone mouth angle of the cone shell is greater than 60°.

[0011] The beneficial effects of the present invention are that, through reasonable structural design, the present invention can effectively avoid cracks on the shoulder of the outer tube under high temperature, high pressure and high flow, reduce the stress on the shoulder of the tee, increase the service life of the pipeline, increase safety, and improve the stability of the use of the tee; and is suitable for high temperature, high pressure and high flow conditions; the elbow structure prevents the cold and hot fluids from intersecting at the shoulder of the guide pipe, thereby increasing the stability of the guide pipe; the orifice structure allows the cold fluid to flow in the interlayer between the tee and the guide pipe, thereby making the temperature field more uniform; and the equipment structure is simple. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0013] Figure 1 It is a cross-sectional view of the overall structure of the present invention;

[0014] Figure 2 It is a cross-sectional front view of the present invention;

[0015] Figure 3 This is the overall structural cross-section of a conventional tee;

[0016] Figure 4 It is a cross-sectional front view of a conventional tee;

[0017] Figure 5 To optimize the overall structural profile of the tee;

[0018] Figure 6 This is a cross-sectional elevation view of the optimized tee;

[0019] Figure 7 Comparison cloud diagrams of simulation results of conventional reducing tees, optimized tees and the present invention; wherein (a) is a stress cloud diagram of a conventional tee, (b) is a stress cloud diagram of an optimized tee, and (c) is a stress cloud diagram of a tee of the present invention;

[0020] In the figure, 1-conical shell, 2-reducing tee, 3-orifice plate, 4-flow guide vertical pipe, 5-flow guide elbow, 6-second flow guide straight pipe, 7-second support block, 8-first flow guide straight pipe, 9-second support block. DETAILED DESCRIPTION

[0021] The present invention is described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the features of the following embodiments and implementations can be combined with each other.

[0022] like Figure 1 As shown, an embodiment of the present invention provides a hot and cold fluid converging guide pipe in a reducing tee, comprising: a reducing tee 2, a first guide straight pipe 8 and a branch pipe; the reducing tee 2 is provided with a first guide straight pipe 8, one end of the first guide straight pipe 8 is provided with a cone shell 1, which is fixedly connected to the port of the reducing tee 2; the other end of the first guide straight pipe 8 is provided with a first support block 9, and a gap is left between the first support block 9 and the reducing tee 2, for reserving the deformation displacement of the first guide straight pipe 8.

[0023] The branch pipe includes a second straight guide pipe, a guide bend pipe 5 and a guide vertical pipe 4; the second straight guide pipe 6 is arranged in the first straight guide pipe 8, and a second support block 7 is provided at one end of the second straight guide pipe 6. A gap is left between the second support block 7 and the first straight guide pipe 8 to reserve the deformation displacement of the second straight guide pipe 6; the other end of the second straight guide pipe 6 is fixedly connected to the guide vertical pipe 4 through the guide bend pipe 5; the guide bend pipe 5 is used for guiding to avoid excessive thermal stress on the shoulder of the guide pipe.

[0024] An orifice plate 3 is provided at the port of the guide riser 4, and the orifice plate 3 is used to inject cold fluid into the interlayer between the reducing tee 2 and the branch pipe to play a role in liquid diversion. By injecting cold fluid, the temperature of the shoulder of the reducing tee 2 is made uniform, avoiding excessive thermal stress and preventing the shoulder of the reducing tee 2 from cracking.

[0025] With conventional reducing tee ( Figure 3 and Figure 4 ) and optimized tee ( Figure 5 and Figure 6 ) is used as a comparison object, and simulation calculations are performed on the present invention to verify the stability of its structure.

[0026] The conventional reducing tee model (DN300-150 reducing tee) is selected according to the standard specification GB / T 12459-2017 "Types and parameters of steel butt-welded pipe fittings", the wall thickness is selected according to "HG / T 20553-2011 Chemical piping seamless and welded steel pipe size selection sequence", the pipe material is austenitic stainless steel S34779, the material grade is 347H, the design specification is GB / T5310-2017 "Seamless steel pipe for high-pressure boilers", the design pressure is 12.8MPa, the inlet fluid temperature of the main pipe DN300 is 400℃, and the inlet fluid temperature of the branch pipe DN150 is 60℃. The fluid is air, and the inlet mass flow rate is 1.6kg / s; the outer surface of the pipe is equipped with insulation.

[0027] The specific dimensions of the optimized tee are shown in Table 1, and the specific dimensions of the present invention are shown in Table 2. The outlet of the guide pipe is 508 mm away from the axis of the branch pipe, and four small support plates are provided at the end of the branch pipe, with gaps between the support plates and the outer pipe to reserve deformation displacement of the guide pipe.

[0028] Table 1: Optimized tee dimensions (unit: mm)

[0029]

[0030] Table 2: Tee dimensions of the present invention (unit: mm)

[0031]

[0032] The solid material is 07Cr18Ni11Nb (347H), which is selected according to GB / T 20801.2-2020 "Pressure Pipe Specification Industrial Pipe Part 2: Materials" and GB / T24511-2017 "Stainless Steel and Heat-resistant Steel Plates and Strips for Pressure Equipment". The allowable value is selected according to GB / T 20801.2-2020 "Pressure Pipe Specification Industrial Pipe Part 2: Materials". At the design temperature of 400°C, S m =90.6MPa, see Table 3 for details.

[0033] Table 3: Permissible values ​​of material strength verification (400℃)

[0034]

[0035] Conventional reducing tees, optimized tees and the present invention are used as simulation objects and studied using ANSYS software. First, the temperature field of the tee is calculated through thermal fluid-solid coupling simulation, and then the load is applied to the structural analysis to perform stress analysis and calculation.

[0036] Considering the simulation working conditions, different settings are made for the simulation, and the parameters at different temperatures during the simulation are calculated using the linear interpolation method. Apply vertical downward gravity acceleration to the tee, set the end face at the cold flow inlet as a fixed end face and apply a reaction force of 21.55MPa, apply a reaction force of 23.14MPa to the end face of the main pipe, and apply the design pressure value to the inner wall of the pipe. Tee simulation working conditions under the self-weight (W) of the tee, design pressure (P=12.8MPa) and applied temperature field (T). Three types of tees are simulated according to the working conditions (W+P+T), and the results under the working conditions are analyzed. Use CFD to perform thermal fluid-solid coupling on the tee, and select the standard k-ω turbulence model.

[0037] Stress assessment is carried out according to the provisions of JB4732-1995 "Steel Pressure Vessels - Analysis and Design Standards".

[0038] The S of three different tees was calculated by simulation. I ~S V , select the more dangerous stress points to make multiple stress check lines along the thickness, and perform linearization on the stress intensity of the tee. Finally, according to the above regulations, the stress strength of the tees of the three structures is checked.

[0039] The allowable value of stress intensity of the three structures according to the primary local membrane stress plus the primary bending stress and the secondary stress is 3S m To assess, namely:

[0040] S IV ≤3S m ;

[0041] The results are as follows Figure 7 As shown, (a) is a conventional tee stress cloud diagram, (b) is an optimized tee stress cloud diagram, and (c) is a tee stress cloud diagram of the present invention. The conventional tee result does not meet the allowable limit value. The maximum stress intensity of the connecting pipe calculated by the optimized tee model is 349.57MPa, and the maximum stress intensity of the connecting pipe calculated by the tee model of the present invention is 317.82MPa, both of which are less than 3 times the allowable stress. The structural strength of the tee model of the present invention better meets the requirements.

[0042] The above embodiments are only used to illustrate the design ideas and features of the present invention, and their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. The protection scope of the present invention is not limited to the above embodiments. Therefore, any equivalent changes or modifications made based on the principles and design ideas disclosed by the present invention are within the protection scope of the present invention.

Claims

1. A three-way cold and hot fluid converging and guiding pipe with different diameters, characterized in that: include: A reducing tee, a first flow guiding straight pipe and a branch pipe; the reducing tee is provided with a first flow guiding straight pipe, one end of the first flow guiding straight pipe is provided with a cone shell, and is fixedly connected to the port of the reducing tee; the other end of the first flow guiding straight pipe is provided with a first support block, and a gap is left between the first support block and the reducing tee, so as to reserve the deformation displacement of the first flow guiding straight pipe; The branch pipe includes a second flow-guiding straight pipe and a flow-guiding vertical pipe; the second flow-guiding straight pipe is arranged in the first flow-guiding straight pipe, a second support block is arranged at one end of the second flow-guiding straight pipe, and a gap is left between the second support block and the first flow-guiding straight pipe for reserving the deformation displacement of the second flow-guiding straight pipe; the other end of the second flow-guiding straight pipe is fixedly connected to the flow-guiding vertical pipe.

2. The reducing tee internal cold and hot fluid converging and guiding pipe according to claim 1, characterized in that: The branch pipe includes a diversion elbow, and the second diversion straight pipe is connected to the diversion vertical pipe through the diversion elbow; the diversion elbow is used for diversion to avoid excessive thermal stress on the shoulder of the diversion pipe.

3. The reducing tee internal cold and hot fluid converging and guiding pipe according to claim 1, characterized in that: The port of the guide riser is provided with an orifice plate, which is used to inject cold fluid into the interlayer between the reducing tee and the branch pipe to play a role in liquid diversion. By injecting cold fluid, the temperature of the shoulder of the reducing tee is made uniform, avoiding excessive thermal stress and preventing the shoulder of the reducing tee from cracking.

4. The reducing tee internal cold and hot fluid converging and guiding pipe according to claim 1, characterized in that: The number of the first supporting blocks is 4, and the number of the second supporting blocks is 4.

5. The reducing tee internal cold and hot fluid converging and guiding pipe according to claim 1, characterized in that: The cone mouth angle of the cone shell is greater than 60°.

Images