CN109611934B

CN109611934B - Simple pipe-in-pipe geothermal circulating system

Info

Publication number: CN109611934B
Application number: CN201810032814.1A
Authority: CN
Inventors: 陈友苗; 陈奎宏
Original assignee: Individual
Current assignee: Individual
Priority date: 2018-01-13
Filing date: 2018-01-13
Publication date: 2022-03-22
Anticipated expiration: 2038-01-13
Also published as: CN109611934A

Abstract

The invention belongs to the technical field of geothermal circulating systems, and particularly relates to a simple pipe-in-pipe geothermal circulating system which comprises a water heater, a circulating pump, an initial joint, a main pipeline and a geothermal pipeline which are sequentially connected, wherein the output end of the water heater is connected with the circulating pump, and the output end of the circulating pump is communicated with the initial joint; the starting joint comprises a starting joint main body, and a starting joint liquid inlet end connected with the output end of the circulating pump, a starting joint connecting end connected with the main pipeline and a starting joint liquid outlet end connected with the liquid inlet end of the water heater are respectively arranged on the starting joint main body; the main pipeline is provided with at least one geothermal pipeline, the geothermal pipeline is formed by a geothermal pipe middle pipe, and the geothermal pipe middle pipe comprises a geothermal outer pipe with a heat conduction function and a geothermal inner pipe with a heat insulation function. The invention has the characteristics of simple structure, low cost, convenient installation, uniform heating and the like.

Description

Simple pipe-in-pipe geothermal circulating system

Technical Field

The invention belongs to the technical field of geothermal circulation systems, and particularly relates to a simple pipe-in-pipe geothermal circulation system.

Background

In the technical field of floor heating systems, the floor heating system is mainly divided into low-temperature hot water floor radiation heating water floor heating and heating cable floor radiation heating electric floor heating according to different heating modes. The low-temperature hot water ground radiation heating is a heating mode that hot water with the temperature not higher than 60 ℃ is used as a heating medium, the hot water circularly flows in a heating pipe to heat a floor, and heat is supplied to the indoor through the ground in a radiation and convection heat transfer mode.

At present, the existing water geothermal circulation has the following disadvantages:

1. because inlet tube and wet return are all separately partd, consequently the ground heating pipeline is very much, and the overall arrangement is difficult, if the room of dysmorphism, two root pipes are difficult to wind very much, and installation space is bigger moreover. For example: for a dozen example of six houses, 12 tubes are needed.

2. The pipeline is heated unevenly, the pipeline at the end just entering the floor is relatively hot, the water return end of the pipeline is not hot, the temperature difference between adjacent pipes is relatively large, and the comfort feeling is discounted. In addition, this can lead to deformation of the ground and even cracking.

3. Some heat sources are relatively hot, and particularly heat sources for supplying heat to urban pipe networks need to be additionally provided with a water mixing valve, so that the installation cost is increased.

Disclosure of Invention

The invention aims to provide a simple pipe-in-pipe geothermal circulating system which is simple in structure, low in cost, convenient to install and uniformly heated.

The purpose of the invention is realized as follows:

a simple pipe-in-pipe geothermal circulating system comprises a water heater, a circulating pump, an initial joint and a geothermal pipeline which are connected in sequence,

the output end of the water heater is connected with a circulating pump, and the output end of the circulating pump is communicated with an initial joint;

the starting joint comprises a starting joint main body, wherein a starting joint liquid inlet end connected with the output end of the circulating pump, a starting joint connecting end connected with the geothermal pipeline and a starting joint liquid outlet end connected with the liquid inlet end of the water heater are respectively arranged on the starting joint main body;

the geothermal pipeline is composed of a geothermal pipe middle pipe, the geothermal pipe middle pipe comprises a geothermal outer pipe with a heat conduction function and a geothermal inner pipe with a heat insulation function, the geothermal inner pipe is coaxially arranged in the geothermal outer pipe through at least one reinforcing rib C, a hot water flow channel is arranged in the geothermal inner pipe, a return water flow channel is arranged in the geothermal outer pipe, the sectional area of the hot water flow channel is equal to that of the return water flow channel, the temperature in the hot water flow channel can be conducted to the return water flow channel through the geothermal inner pipe, and the temperature of the return water flow channel is balanced.

Preferably, the materials of the geothermal outer pipe and the geothermal inner pipe are both PERT or PB, hollow glass beads or plastic foaming agents are added into the materials of the geothermal inner pipe, so that the heat conductivity coefficient of the geothermal outer pipe is controlled to be 0.1w/mK-0.44w/mK, and the length of the pipeline is in direct proportion to the heat conductivity coefficient.

Preferably, a main pipeline is arranged between the starting joint and the geothermal pipeline, the main pipeline is formed by a pipe head in a hot water pipe, the pipe head in the hot water pipe comprises a hot water outer pipe and a hot water inner pipe which have heat insulation functions, the hot water inner pipe is coaxially arranged in the hot water outer pipe through at least one reinforcing rib A, a hot water flow passage is arranged in the hot water inner pipe, and a return water flow passage is arranged in the hot water outer pipe.

Preferably, the materials of the hot water outer pipe and the hot water inner pipe are both PPR or PB, and hollow glass beads or plastic foaming agents are added into the materials of the hot water inner pipe, so that the thermal conductivity of the materials is controlled to be 0.05w/mK-0.4 w/mK.

Preferably, the liquid inlet end of the geothermal pipeline is provided with a micro water pump and a control joint, the control joint comprises a control joint liquid inlet end connected with the main pipeline, a control joint liquid outlet end connected with the geothermal pipeline and a control joint fixed end connected with the micro water pump, a control joint inner pipe is arranged between the control joint liquid inlet end and the control joint liquid outlet end, the outer wall of the control joint inner pipe is provided with an isolation rib, and the isolation rib divides the backflow cavity of the control joint into two parts which are communicated with each other through the micro water pump; the tail ends of the geothermal pipelines are connected through plugs, and the plugs are communicated with hot water runners and return water runners of pipes in the geothermal pipes.

Preferably, the inlet end of the micro water pump is provided with a backflow check valve.

Preferably, the tail end of the geothermal pipeline is connected with a control valve through a pipe joint, and the control valve controls the opening and closing of the hot water flow channel.

Preferably, the control valve is an electric heating cut-off valve, an electromagnetic cut-off valve or a manual cut-off valve.

Preferably, the main pipeline and the geothermal pipeline are provided with pipe joints, each pipe joint comprises a hollow joint main body, each joint main body at least comprises two outer pipe connecting ends, and each outer pipe connecting end is formed with a threaded part or a hot melting part or a clamping part; the joint main part is internally provided with a connecting inner pipe through a reinforcing rib B, and the end part of the connecting inner pipe is provided with an inner pipe connecting position.

Preferably, the geothermal pipelines comprise a primary geothermal pipeline and a secondary geothermal pipeline, the primary geothermal pipeline is connected with a plurality of secondary geothermal pipelines through pipe joints, and the secondary geothermal pipelines are respectively provided with a plurality of geothermal pipe middle pipes in parallel through the pipe joints.

Compared with the prior art, the invention has the outstanding and beneficial technical effects that:

1. the invention is suitable for the users of the southern small house type, has simple structure and few pipelines, and is convenient for the layout of rooms with infrequent floor heating in the southern.

2. The invention designs a pipe-in-pipe for a floor heating circulating system, wherein the outer pipe dissipates heat, the inner pipe preserves heat, the sectional area of a hot water runner is equal to that of a return water runner, so that the liquid inlet amount and the liquid outlet amount are kept consistent, and the fluctuation of a pipeline is reduced. Because the geothermal inner pipe is not absolutely heat-insulating, the temperature in the hot water flow channel can be conducted into the return water flow channel through the geothermal inner pipe, the temperature T1 at the liquid inlet end of the geothermal inner pipe, the temperature T2 at the liquid outlet end of the geothermal inner pipe, the temperature T3 at the liquid inlet end of the geothermal outer pipe and the temperature T4 at the liquid outlet end of the geothermal outer pipe are respectively, for a pipe-in-pipe pipeline, the temperature T1 at the liquid inlet end of the geothermal inner pipe and the temperature T4 at the liquid outlet end of the geothermal outer pipe at the same position can conduct heat, the more heat is conducted when the temperature difference is larger, the more heat is conducted at the liquid inlet end of the geothermal inner pipe in unit area, the temperature of T4 can be guaranteed to be approximately equal to the temperature of T3 after heat conduction, and the same reason is also applied to other places of the geothermal outer pipe, so that the temperature of the return water flow channel is balanced. Through such self-balancing, replaced the effect of muddy water valve among the traditional underfloor heating system, guarantee that the temperature in every place in room is exactly equal for the certain limit that the temperature in whole room can be controlled. The floor temperature ratio at the position of the water return pipe is lower, the floor temperature at the position of the water inlet pipe is relatively higher, and the local hot and local cold conditions are generated, so that the comfort of people is greatly increased.

3. The pipe material of the invention is preferably PERT, PPR and PB, because the PERT pipe material has higher heat conductivity coefficient than PPR, and the higher the PERT pipe material is, the easier the PERT pipe material is to conduct heat, so that PERT is more suitable for geothermal systems, and PPR is more suitable for hot water systems. The hollow glass beads or the plastic foaming agent is added in the key processing process, so that the heat conductivity coefficient of the pipe is reduced, and the heat insulation performance is improved. The traditional mode is to add a plastic foaming agent, so that small air holes are added after forming to reduce the heat conductivity coefficient, but the produced pipe has the problem of low hardness and strength, so that the hollow glass beads are added through continuous research and improvement, and the main characteristics of the hollow glass beads are that the density is smaller than that of the glass beads, and the heat conductivity is poor. The weight of the pipe fitting is reduced, and the strength and the heat insulation effect of the pipe fitting are improved.

4. The invention designs the main pipeline as a hot water pipe-in-pipe, namely an inner heat-insulating pipe and an outer heat-insulating pipe, because the aperture ratio of the inner pipe is smaller, the amount of cold water in the inner pipe is less at the beginning, water resources are saved, and the function of quickly discharging hot water can be realized; the inner pipe and the outer pipe made of the heat insulation material can increase the heat insulation property, and the heat dissipated by the inner pipe can be absorbed by the hot water in the outer pipe and circulated to the heater, so that the energy is saved; the pipe in the single pipe, the distribution of easy design pipeline, easy to assemble has practiced thrift the cost of labor greatly.

Drawings

Fig. 1 is a schematic structural diagram of a first embodiment of the piping layout of the present invention.

FIG. 2 is a cross-sectional view of a head-end micro water pump control in a first embodiment of a piping layout of the present invention;

fig. 3 is a schematic structural diagram of a second embodiment of the piping layout of the present invention.

FIG. 4 is a cross-sectional view of control of the tail control valve in a second embodiment of the piping arrangement of the present invention;

fig. 5 is a schematic structural diagram of a third embodiment of the piping arrangement of the present invention.

Fig. 6 is a schematic structural diagram of a fourth embodiment of the piping arrangement of the present invention.

Fig. 7 is a schematic structural view of a first embodiment of the starting valve of the present invention.

Fig. 8 is a schematic view of the use of the first embodiment of the starting valve of the present invention.

Fig. 9 is a schematic structural view of a second embodiment of the starting valve of the present invention.

Fig. 10 is a schematic view of the construction of a third embodiment of the starting valve of the present invention.

Fig. 11 is a schematic view showing the structure of a first embodiment of the pipe in the hot water pipe of the present invention.

Fig. 12 is a schematic view showing the structure of a second embodiment of the pipe in the hot water pipe according to the present invention.

Fig. 13 is a schematic structural view of a third embodiment of a pipe in a hot water pipe according to the present invention.

Fig. 14 is a schematic view of a reinforcing rib in the tube of the geothermal tube according to the present invention.

Fig. 15 is a schematic structural view of two reinforcing ribs in the pipe of the geothermal pipe.

FIG. 16 is a cross-sectional view of a flat tee joint joined by a heat stake of the present invention.

FIG. 17 is a cross-sectional view of a planar four-way joint joined by a heat stake portion of the present invention.

FIG. 18 is a cross-sectional view of a two-way straight pipe joint having a threaded portion at one end and a heat-fused portion at the other end according to the present invention.

FIG. 19 is a cross-sectional view of a two-way right angle connector of the hot melt attachment of the present invention.

FIG. 20 is a cross-sectional view of a spatial three-way right angle fitting connected by a hot melt of the present invention.

FIG. 21 is a cross-sectional view of a planar half angle two-way joint joined by a heat stake portion of the present invention.

FIG. 22 is a cross-sectional view of a two-way joint joined by a heat stake portion of the present invention.

FIG. 23 is a cross-sectional view of a two-way connector with one end snap-fit portion and one end heat-fusible portion connected according to the present invention.

FIG. 24 is a second cross-sectional view of a two-way connector with a snap-fit portion at one end and a heat-fusible portion at one end in accordance with the present invention.

Fig. 25 is a schematic structural diagram of a fifth embodiment of the piping arrangement of the present invention.

The reference numerals in the figures denote the meanings:

1-a main pipeline; 2-a circulating pump; 3-an initial linker; 4-geothermal piping; 5-plug; 6-a water heater; 7-pipe joint; 8-a miniature water pump; 9-control joint;

10-hot water pipe in pipe; 11-hot water outer pipe; 11 a-inner sleeve; 11 b-a heat-insulating inner sleeve; 11 c-outer sleeve;

12-hot water inner pipe; 12 a-an inner base tube; 12 b-a first insulating layer;

13-reinforcing rib A; 15-a second insulating layer;

21-a connector body; 22-outer tube connection end; 23-reinforcing rib B; 24-inner tube connection site; 24 a-a guide; 24 b-a stop; 25-connecting the inner tube; 26-a control valve;

30-geothermal pipe-in-pipe; 31-geothermal outer tube; 32-geothermal inner tube; 33-reinforcing rib C;

301-starting joint body; 302-initial joint inlet end; 303-initial joint connection end; 304-initial joint liquid outlet end; 305-starting joint inner tube; 306-starting joint outer tube; 307-annular seal groove; 308-flared opening a; 309-a connecting part; 310-common joint; 311-pipe-in-pipe joint; 312-annular seal.

Detailed Description

The invention is further described below with reference to specific examples:

the first embodiment is as follows:

as shown in fig. 1-2, a simple tube-in-tube geothermal circulating system comprises a water heater 6, a circulating pump 2, an initial joint 3, a main pipeline 1 and a geothermal pipeline 4 which are connected in sequence,

the output end of the water heater 6 is connected with the circulating pump 2, and the output end of the circulating pump 2 is communicated with the initial joint.

[ STARTING JOINT ]

As shown in fig. 7-8, the starting joint 3 includes a starting joint main body 301, the starting joint main body 301 is respectively provided with a starting joint liquid inlet end 302 connected to the output end of the circulation pump 2, a starting joint connection end 303 connected to the main pipeline 1, and a starting joint liquid outlet end 304 connected to the liquid inlet end of the water heater 6, the starting joint main body 301 is composed of a starting joint inner tube 305 and a starting joint outer tube 306, a starting joint inner tube 305 is provided between the starting joint liquid inlet end 302 and the starting joint connection end 303, and the starting joint liquid outlet end 304 is communicated with the inner cavity of the starting joint outer tube 306.

Preferably, the start joint inner tube 305 and the start joint outer tube 306 are integrally formed, which facilitates processing.

Preferably, the initial joint inlet end 302, the initial joint connecting end 303 and the initial joint outlet end 304 are respectively formed with internal threads or external threads.

Preferably, the initial joint inlet end 302 is formed with internal threads, and the initial joint connecting end 303 and the initial joint outlet end 304 are formed with external threads.

Preferably, a seal groove 307 for installing a seal ring is arranged on the end face of the starting joint outer tube 306 of the starting joint connecting end 303, so that the sealing performance of the connecting position is improved.

Preferably, the liquid inlet end of the inner pipe 305 of the starting joint is provided with a horn-shaped opening a308, and the horn-shaped opening a308 is beneficial to increasing the flow rate of liquid in the inner pipe, reducing the pressure loss of liquid generated by the reduction of a pipeline and facilitating liquid inlet; the inner wall of the liquid outlet end of the starting joint inner pipe 305 is provided with an inclined connecting part 309, so that the starting joint inner pipe can be conveniently connected with the inner pipe of a pipe-in-pipe or the inner pipe of a pipe-in-pipe joint, the sealing effect is improved, and the starting joint inner pipe is convenient to install.

Preferably, the initial joint liquid inlet end 302 and the initial joint connecting end 303 are coaxially arranged on the initial joint main body 301, and the initial joint liquid outlet end 304 is arranged on the side wall of the initial joint main body 301 and communicated with the inner cavity of the initial joint outer pipe 306. The embodiment is more convenient for die sinking processing and is beneficial to reducing the production cost.

The starting valve also exists in the form of:

1. as shown in fig. 9, the initial joint liquid inlet end 302 and the initial joint liquid outlet end 304 are coaxially arranged on the initial joint main body 301, the initial joint connection end 303 is arranged on the side wall of the initial joint main body 301, and an initial joint inner pipe 305 is arranged between the initial joint liquid inlet end 302 and the initial joint connection end 303 in a bending mode.

2. As shown in fig. 10, the initial joint connection end 303 and the initial joint liquid outlet end 304 are coaxially arranged on the initial joint main body 301, the initial joint liquid inlet end 302 is arranged on the side wall of the initial joint main body 301, and an initial joint inner pipe 305 is arranged between the initial joint liquid inlet end 302 and the initial joint connection end 303 in a bending mode.

[ geothermal pipe in pipe ]

As shown in fig. 14-15, at least one geothermal pipe 4 is disposed on the main pipe 1, the geothermal pipe 4 is formed by a geothermal pipe-in-pipe 30, the diameter of the geothermal pipe-in-pipe is 6 minutes and 4 minutes, which are generally smaller than the diameter of the main pipe by one, the geothermal pipe-in-pipe 30 includes a geothermal outer pipe 31 having a heat conduction function and a geothermal inner pipe 32 having a heat insulation function, the geothermal inner pipe 32 is coaxially disposed in the geothermal outer pipe 31 by at least one reinforcing rib C33, a hot water flow passage is disposed in the geothermal inner pipe 32, a return water flow passage is disposed in the geothermal outer pipe 31, the cross-sectional area of the hot water flow passage is equal to the cross-sectional area of the return water flow passage, and the temperature in the hot water flow passage can be conducted to the return water flow passage through the geothermal inner pipe 32 to balance the temperature of the return water flow passage. The number of the reinforcing ribs C33 is not too large easily because the pipelines are coiled in the geothermal circulating system, and the reinforcing ribs C33 are more and stronger and are not easy to install, so the number is generally 1 or 2.

Preferably, the materials of the geothermal outer pipe 31 and the geothermal inner pipe 32 are both PERT or PB, hollow glass beads or plastic foaming agents are added into the material of the geothermal inner pipe 32, so that the thermal conductivity of the geothermal outer pipe is controlled to be 0.1w/mK-0.4w/mK, and the length of the pipe is in direct proportion to the thermal conductivity.

Preferably, the materials of the geothermal outer pipe 31 and the geothermal inner pipe 32 are both PERT or PB, hollow glass beads or plastic foaming agents are added into the materials of the geothermal inner pipe 32, so that the thermal conductivity of the geothermal outer pipe is controlled to be 0.1w/mK-0.4w/mK, and when a pipeline is designed, the length of the pipeline is in direct proportion to the thermal conductivity.

The invention designs a pipe-in-pipe for a floor heating circulating system, wherein the outer pipe dissipates heat, the inner pipe preserves heat, the sectional area of a hot water runner is equal to that of a return water runner, so that the liquid inlet amount and the liquid outlet amount are kept consistent, and the fluctuation of a pipeline is reduced. Because the geothermal inner pipe is not absolutely heat-insulating, the temperature in the hot water flow channel can be conducted into the return water flow channel through the geothermal inner pipe, the temperature T1 at the liquid inlet end of the geothermal inner pipe, the temperature T2 at the liquid outlet end of the geothermal inner pipe, the temperature T3 at the liquid inlet end of the geothermal outer pipe and the temperature T4 at the liquid outlet end of the geothermal outer pipe are respectively, for a pipe-in-pipe pipeline, the temperature T1 at the liquid inlet end of the geothermal inner pipe and the temperature T4 at the liquid outlet end of the geothermal outer pipe at the same position can conduct heat, the more heat is conducted when the temperature difference is larger, the more heat is conducted at the liquid inlet end of the geothermal inner pipe in unit area, the temperature of T4 can be guaranteed to be approximately equal to the temperature of T3 after heat conduction, and the same reason is also applied to other places of the geothermal outer pipe, so that the temperature of the return water flow channel is balanced. Through such self-balancing, replaced the effect of muddy water valve among the traditional underfloor heating system, guarantee that the temperature in every place in room is exactly equal for the certain limit that the temperature in whole room can be controlled. The floor temperature ratio at the position of the water return pipe is lower, the floor temperature at the position of the water inlet pipe is relatively higher, and the local hot and local cold conditions are generated, so that the comfort of people is greatly increased.

[ Hot Water pipe in pipe ]

As shown in fig. 11, the main pipeline 1 is composed of a hot water pipe middle pipe head 10 and a pipe joint 7, wherein the hot water pipe middle pipe is a heat preservation pipe and is a 6-minute pipe or a 1-inch pipe. The tube head 10 comprises a hot water outer tube 11 and a hot water inner tube 12 which have heat insulation functions, the hot water inner tube 12 is coaxially arranged in the hot water outer tube 11 through at least one reinforcing rib A13, a hot water flow passage is arranged in the hot water inner tube 12, and a return water flow passage is arranged in the hot water outer tube 11. The greater the number of ribs a13, the greater the strength of the tube and the less likely it will bend.

Preferably, the ratio of the sectional area of the hot water flow passage to the sectional area of the return water flow passage is 1: 1.

Preferably, a plurality of centrosymmetric or axisymmetric reinforcing ribs A13 are arranged between the hot water outer pipe 11 and the hot water inner pipe 12.

Preferably, the materials of the hot water outer pipe 11 and the hot water inner pipe 12 are both PPR or PB, and during the manufacturing process, the material of the hot water inner pipe 12 is added with nontoxic plastic foaming agents such as hollow glass beads or baking soda, so that the thermal conductivity is controlled to be 0.05w/mK-0.4w/mK, and the thermal conductivity is reduced to 20% -70% of the original thermal conductivity of the material.

The hollow glass bead is a specially processed glass bead, is a micron-grade novel light material developed in the fifth and sixty years of the last century, mainly comprises borosilicate, has the general particle size of 10-250 mu m and the wall thickness of 1-2 mu m, has the characteristics of high compressive strength, high melting point, high electrical resistivity, small thermal conductivity and thermal contraction coefficient and the like, and is known as a space time material in the 21 st century. The hollow glass beads have obvious weight reduction, sound insulation and heat preservation effects, so that the product has good anti-cracking performance and reprocessing performance, is widely used in composite materials such as glass fiber reinforced plastics, artificial marble, artificial agate and the like, and in the fields of petroleum industry, aerospace, novel high-speed trains, automobile ships, heat insulation coatings and the like, and effectively promotes the development of scientific and technological industry in China.

The invention designs the pipe-in-pipe for the hot water circulating system, because the diameter ratio of the inner pipe is smaller, the amount of cold water in the inner pipe is less at the beginning, water resources are saved, and the function of quickly discharging hot water can be realized; the inner pipe and the outer pipe made of the heat insulation material can increase the heat insulation property, and the heat dissipated by the inner pipe can be absorbed by the hot water in the outer pipe and circulated to the heater, so that the energy is saved; the pipe in the single pipe, the distribution of easy design pipeline, easy to assemble has practiced thrift the cost of labor greatly.

The hot water pipe also has the following forms:

1. as shown in fig. 12: and a second heat-insulating layer 15 is formed on the inner wall of the hot water outer pipe 11, and the second heat-insulating layer 15, the reinforcing ribs A13 and the hot water inner pipe 12 are integrally formed by the same heat-insulating material. The heat insulation material is prepared by adding hollow glass beads or plastic foaming agent in the processing process of the PPR material.

2. As shown in fig. 13: the hot water inner pipe 12 is composed of an inner base pipe 12a and a first heat insulating layer 12b provided in the inner base pipe 12a, and the inner base pipe 12a, the reinforcing rib a13 and the hot water outer pipe 11 are integrally formed of the same material.

Preferably, the hot water outer pipe 11 is composed of an inner sleeve 11a, a heat insulating inner sleeve 11b and an outer sleeve 11c, the inner and outer walls of the heat insulating inner sleeve 11b are respectively provided with the inner sleeve 11a and the outer sleeve 11c, and the inner sleeve 11a, the reinforcing rib a13 and the inner base pipe 12a are integrally formed by the same material.

Introduction of materials:

PPRpolypropylene random: the polypropylene random copolymer has the advantages of good toughness, high strength, excellent processing performance, good creep resistance at higher temperature, and high transparency peculiar to the polypropylene random copolymer, and can be widely used for producing pipes, sheets, daily necessities, packaging materials, household appliance parts and various films.

PERT: the medium density polyethylene is produced by adopting a special molecular design and synthesis process, the method of copolymerizing ethylene and octene is adopted, and a unique molecular structure is obtained by controlling the number and distribution of side chains to improve the heat resistance of the PE pipe, and the heat resistance maximum temperature of the PE pipe is 60 degrees. Because of the existence of octene short chain branch, PE macromolecule can not be crystallized in a sheet crystal, but can penetrate through several crystals to form connection between crystals, which keeps good flexibility, high heat conductivity and inertia of PE pipe, and makes it have better pressure resistance, and can be used for hot water transportation below 60 ℃ for a long time. The PE-modified polyurethane elastomer retains the good flexibility and inertia of PE, and has the advantages of low temperature resistance of-40 ℃, good impact resistance, better pressure resistance, no toxicity, no odor, no pollution, environmental protection and recyclability. The PE-RT pipe can be connected in a hot melting way, and is convenient to install and maintain.

PB: a high-molecular inert polymer for 20 th century and 70 th era. It has high temperature resistance, durability, chemical stability and plasticity, is tasteless, odorless and nontoxic, is one of the most advanced chemical materials in the world at present, and has the reputation of plastic gold. The material is light in weight; the flexibility is good; the corrosion resistance is high, the high temperature resistance is particularly outstanding when the high-temperature-resistant composite material is used for pressure pipelines, the high-temperature-resistant composite material can be used for a long time at the temperature of 95 ℃, and the maximum service temperature can reach 110 ℃. The surface roughness of the pipe is 0.007, no scale is formed, heat preservation is not needed, water quality is protected, and the using effect is good.

The pipe of the present invention is preferably PERT and PPR, because PERT pipe has a higher thermal conductivity than PPR, and the higher the thermal conductivity, the easier the thermal conductivity, so PERT is more suitable for geothermal system, and PPR is more suitable for hot water system. The hollow glass beads or the plastic foaming agent is added in the key processing process, so that the heat conductivity coefficient of the pipe is reduced, and the heat insulation performance is improved. The traditional mode is to add a plastic foaming agent, so that small air holes are added after forming to reduce the heat conductivity coefficient, but the produced pipe has the problem of low hardness and strength, so that the hollow glass beads are added through continuous research and improvement, and the main characteristics of the hollow glass beads are that the density is smaller than that of the glass beads, and the heat conductivity is poor. The weight of the pipe fitting is reduced, and the strength and the heat insulation effect of the pipe fitting are improved.

[ control joints ]

As shown in fig. 2, preferably, a micro water pump 8 and a control joint 9 are arranged at the liquid inlet end of the geothermal pipeline 4, the control joint 9 comprises a control joint liquid inlet end connected with the main pipeline 1, a control joint liquid outlet end connected with the geothermal pipeline 4 and a control joint fixed end connected with the micro water pump 8, a control joint inner pipe is arranged between the control joint liquid inlet end and the control joint liquid outlet end, the outer wall of the control joint inner pipe is provided with an isolation rib, and the isolation rib divides the backflow cavity of the control joint into two parts and is communicated with each other through the micro water pump 8; the tail ends of the geothermal pipelines 4 are connected through plugs 5, and the plugs 5 are communicated with a hot water flow channel and a return water flow channel of the tube 30 in the geothermal tube.

Preferably, the inlet end of the micro water pump 8 is provided with a backflow check valve.

[ PIPE JOINT ]

As shown in fig. 16-24, the pipe joint comprises a hollow joint main body 21, wherein the joint main body 21 at least comprises two outer pipe connecting ends 22, and the outer pipe connecting ends 22 are formed with thread parts or hot melting parts or clamping parts; the clamping portion is provided with a clamping convex ring and then fixed through a nut.

The joint main body 21 is internally provided with a connecting inner pipe 25 through a reinforcing rib B23, the end part of the connecting inner pipe 25 is provided with an inner pipe connecting position 24, the connecting position comprises a guiding part 24a and a limiting part 24B, the guiding part 24a facilitates the guiding connection of the pipe-in-pipe inner pipe, and the limiting part 24B is used for limiting the pipe-in-pipe inner pipe. The pipes of the invention are preferably PERT and PPR.

Preferably, the joint body 21 is a two-way pipe, or a three-way pipe, or a four-way pipe.

Example two:

[ Modular geothermal pipeline ]

As shown in fig. 5, the present embodiment is substantially the same as the first embodiment, and the difference is that the position of the control switch is different:

preferably, the geothermal pipe 4 comprises a primary geothermal pipe and a secondary geothermal pipe, the primary geothermal pipe is tapped with a plurality of secondary geothermal pipes through pipe joints 7, and the secondary geothermal pipes are respectively provided with a plurality of geothermal pipe middle pipes 30 in parallel through the pipe joints 7. When meeting the situations of room fillets, corners and the like, the length of the tube 30 in the modular geothermal pipeline can be directly cut to correspond to different room shapes, the operation is simple, construction can be carried out by only one worker, and labor cost is greatly reduced and saved.

Example three:

this embodiment is basically the same as the first embodiment, and the difference is that the position of the control switch is different:

as shown in fig. 3-4, the end of the geothermal pipe 4 is connected to a control valve 26 through a pipe joint 7, and the control valve 26 controls the opening and closing of the hot water flow passage.

Preferably, the control valve 26 is an electric heating cut-off valve, an electromagnetic cut-off valve, a manual cut-off valve or an electric heating valve.

Example four:

as shown in fig. 6, the present embodiment is substantially the same as the first embodiment, and the difference is: the invention has also been used with capillaries that are of the same construction as the geothermal pipe-in-pipe, except that the diameter is smaller, on the order of 4.3MM, than the geothermal pipe-in-pipe. Compared with the complex layout of the traditional capillary tube, the invention is more convenient, and the limitation of installation is greatly reduced.

Simultaneously, the inner wall pressure ratio of capillary is less, and the overall arrangement can be more encrypted than the geothermol power pipe for conduction temperature is more stable, makes the people feel more comfortable.

In addition, the capillary tube with small volume is mainly distributed in the wall and the roof, and is more practical and convenient.

Example five:

as shown in fig. 25, a simple pipe-in-pipe geothermal circulating system comprises a water heater 6, a circulating pump 2, an initial joint 3 and a geothermal pipeline 4 which are connected in sequence,

the output end of the water heater 6 is connected with the circulating pump 2, and the output end of the circulating pump 2 is communicated with the starting joint;

the starting joint 3 comprises a starting joint main body 301, the starting joint main body 301 is respectively provided with a starting joint liquid inlet end 302 connected with the output end of the circulating pump 2, a starting joint connecting end 303 connected with the main pipeline 1 and a starting joint liquid outlet end 304 connected with the liquid inlet end of the water heater 6, the starting joint main body 301 is composed of a starting joint inner pipe 305 and a starting joint outer pipe 306, the starting joint inner pipe 305 is arranged between the starting joint liquid inlet end 302 and the starting joint connecting end 303, and the starting joint liquid outlet end 304 is communicated with the inner cavity of the starting joint outer pipe 306;

the geothermal pipeline 4 is composed of a geothermal pipe-in-pipe 30, the geothermal pipe-in-pipe 30 comprises a geothermal outer pipe 31 with a heat conduction function and a geothermal inner pipe 32 with a heat insulation function, the geothermal inner pipe 32 is coaxially arranged in the geothermal outer pipe 31 through at least one reinforcing rib C33, a hot water flow channel is arranged in the geothermal inner pipe 32, a return water flow channel is arranged in the geothermal outer pipe 31, the sectional area of the hot water flow channel is equal to that of the return water flow channel, the temperature in the hot water flow channel can be conducted to the return water flow channel through the geothermal inner pipe 32, and the temperature of the return water flow channel is balanced.

The principle is as follows:

as shown in fig. 1 or 25:

the liquid inlet end 302 of the starting joint is connected with a circulating pump 2 through a common joint, and the circulating pump 2 is connected with a water heater; the joint connecting end 303 is connected with the pipe in the pipe through a pipe in pipe joint 311, and the pipe in the pipes form a heating pipeline of a floor heater. The circulation pump 2 pumps hot water through the start joint into the pipe-in-pipe inner pipe, hot water flows into the outer pipe at the end of the pipe-in-pipe and heats the room, and cooled hot water flows back to the water heater from the liquid outlet end 304 of the start joint and is reheated. The invention is used for connecting the circulating pump 2, conveying hot water to a floor heating pipeline, and collecting cooled water to enable the cooled water to flow back to the water heater.

The above embodiments are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited thereby, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.

Claims

1. A simple pipe-in-pipe geothermal circulating system is characterized in that: comprises a water heater (6), a circulating pump (2), an initial joint (3) and a geothermal pipeline (4) which are connected in sequence,

the output end of the water heater (6) is connected with the circulating pump (2), and the output end of the circulating pump (2) is communicated with the starting joint;

the starting joint (3) comprises a starting joint main body (301), a starting joint liquid inlet end (302) connected with the output end of the circulating pump, a starting joint connecting end (303) connected with the geothermal pipeline (4) and a starting joint liquid outlet end (304) connected with the liquid inlet end of the water heater (6) are respectively arranged on the starting joint main body (301), the starting joint main body (301) is composed of a starting joint inner pipe (305) and a starting joint outer pipe (306), a starting joint inner pipe (305) is arranged between the starting joint liquid inlet end (302) and the starting joint connecting end (303), and the starting joint liquid outlet end (304) is communicated with the inner cavity of the starting joint outer pipe (306);

the geothermal pipeline (4) is composed of a geothermal pipe-in-pipe (30), the geothermal pipe-in-pipe (30) comprises a geothermal outer pipe (31) with a heat conduction function and a geothermal inner pipe (32) with a heat insulation function, the geothermal inner pipe (32) is coaxially arranged in the geothermal outer pipe (31) through at least one reinforcing rib C (33), a hot water flow channel is arranged in the geothermal inner pipe (32), a return water flow channel is arranged in the geothermal outer pipe (31), the sectional area of the hot water flow channel is equal to that of the return water flow channel, the temperature in the hot water flow channel can be conducted into the return water flow channel through the geothermal inner pipe (32), so that the temperature T1 at the inlet end of the geothermal inner pipe is greater than the temperature T2 at the outlet end of the geothermal inner pipe, the temperature T3 at the inlet end of the geothermal outer pipe is greater than the temperature T4 at the outlet end of the geothermal outer pipe, and the temperature of the return water flow channel is balanced;

the liquid inlet end of the geothermal pipeline (4) is provided with a miniature water pump (8) and a control joint (9), the control joint (9) comprises a control joint liquid inlet end connected with the main pipeline (1), a control joint liquid outlet end connected with the geothermal pipeline (4) and a control joint fixed end connected with the miniature water pump (8), a control joint inner pipe is arranged between the control joint liquid inlet end and the control joint liquid outlet end, the outer wall of the control joint inner pipe is provided with an isolation rib, and the isolation rib divides a backflow cavity of the control joint into two parts which are communicated with each other through the miniature water pump (8); the tail ends of the geothermal pipelines (4) are connected through a blocking cap (5), and the blocking cap (5) is communicated with a hot water flow passage and a return water flow passage of a geothermal pipe middle pipe (30).

2. The simple pipe-in-pipe geothermal circulation system according to claim 1, wherein: the materials of the geothermal outer pipe (31) and the geothermal inner pipe (32) are both PERT or PB, and hollow glass beads or plastic foaming agents are added into the material of the geothermal inner pipe (32) to control the thermal conductivity coefficient of the geothermal outer pipe to be 0.1w/mK-0.44 w/mK.

3. The simple pipe-in-pipe geothermal circulation system according to claim 1, wherein: be provided with main pipeline (1) between initial joint (3) and geothermol power pipeline (4), pipe head (10) constitute in main pipeline (1) by the hot-water line, pipe head (10) are including hot water outer tube (11) and hot water inner tube (12) that have thermal-insulated function in the hot-water line, hot water inner tube (12) are through at least one strengthening rib A (13) coaxial setting in hot water outer tube (11), be provided with the hot water runner in hot water inner tube (12), be provided with the return water runner in hot water outer tube (11).

4. The simple pipe-in-pipe geothermal circulation system according to claim 3, wherein: the hot water outer pipe (11) and the hot water inner pipe (12) are both made of PPR or PB, and hollow glass beads or plastic foaming agent is added into the hot water inner pipe (12) so that the heat conductivity coefficient is controlled to be 0.05w/mK-0.4 w/mK.

5. The simple pipe-in-pipe geothermal circulation system according to claim 1, wherein: and a backflow check valve is arranged at the liquid inlet end of the micro water pump (8).

6. The simple pipe-in-pipe geothermal circulation system according to claim 1, wherein: the tail end of the geothermal pipeline (4) is connected with a control valve (26) through a pipe joint (7), and the control valve (26) controls the opening and closing of the hot water flow passage.

7. The simple pipe-in-pipe geothermal circulation system according to claim 6, wherein: the control valve (26) is an electric heating stop valve or an electromagnetic stop valve or a manual stop valve or an electric heating stop valve.

8. The simple pipe-in-pipe geothermal circulation system according to claim 1, wherein: the main pipeline (1) and the geothermal pipeline (4) are provided with pipe joints (7), each pipe joint (7) comprises a hollow joint main body (21), each joint main body (21) at least comprises two outer pipe connecting ends (22), and each outer pipe connecting end (22) is formed with a thread part or a hot melting part or a clamping part; the connector is characterized in that a connecting inner pipe (25) is arranged in the connector main body (21) through a reinforcing rib B (23), and inner pipe connecting positions (24) are arranged at the end parts of the connecting inner pipes (25).

9. The simple pipe-in-pipe geothermal circulation system according to claim 1, wherein: the geothermal pipelines (4) comprise a primary geothermal pipeline and a secondary geothermal pipeline, the primary geothermal pipeline is tapped with a plurality of secondary geothermal pipelines through pipe joints (7), and the secondary geothermal pipelines are respectively provided with a plurality of geothermal pipe middle pipes (30) in parallel through the pipe joints (7).