CN212961794U

CN212961794U - Pipeline structure for heat supply pressurizing unit

Info

Publication number: CN212961794U
Application number: CN202021213105.2U
Authority: CN
Inventors: 张路生; 张东宏; 刘�东; 李存智
Original assignee: Liulin Jingde Heating Equipment Co ltd
Current assignee: Shanxi Jingde Technology Co ltd
Priority date: 2020-06-28
Filing date: 2020-06-28
Publication date: 2021-04-13
Anticipated expiration: 2030-06-28

Abstract

The utility model provides a pipeline structure for a heat supply pressurizing unit, which comprises a water supply pipeline, a water return pipeline and a communicating pipe; a first manual flange ball valve, a first filter valve, a circulating pump, a first electric regulating valve, a first check valve and a second manual flange ball valve are sequentially arranged on the water supply pipeline along the water flow direction; a first pressure transmitter and a first temperature sensor are arranged on a pipeline of the water supply pipeline between the first filter valve and the circulating pump; a second pressure transmitter is arranged on a pipeline of the water supply pipeline between the first electric regulating valve and the first check valve; the heating and pressurizing unit is installed to solve the heating problem of residents with redundant areas in a high area.

Description

Pipeline structure for heat supply pressurizing unit

Technical Field

The utility model relates to a heat supply technical field, concretely relates to pipeline structure for heat supply pressurization unit.

Background

The heating plate area of the large central heating unit cannot meet the normal heating requirement of residents because the heights of partial residents exceed the range.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a pipeline structure for heat supply pressure unit.

In order to achieve the above object, the utility model provides a following technical scheme: a pipeline structure for a heat supply pressurizing unit comprises a water supply pipeline, a water return pipeline and a communicating pipe;

a first manual flange ball valve, a first filter valve, a circulating pump, a first electric regulating valve, a first check valve and a second manual flange ball valve are sequentially arranged on the water supply pipeline along the water flow direction; a first pressure transmitter and a first temperature sensor are arranged on a pipeline of the water supply pipeline between the first filter valve and the circulating pump; a second pressure transmitter is arranged on a pipeline of the water supply pipeline between the first electric regulating valve and the first check valve;

the water return pipeline is sequentially provided with a third manual flange ball valve, a second filter valve, a pressure reducing valve, an opening and closing valve, a first electric switch valve and a fourth manual flange ball valve along the water flow direction; a third pressure transmitter is arranged on a pipeline of the water return pipeline between the second filter valve and the pressure reducing valve; a second temperature sensor and a fourth pressure transmitter are arranged on a pipeline of the water return pipeline between the first electric switch valve and the fourth manual flange ball valve;

one end of the communicating pipe is connected with an opening and closing valve on the water return pipeline, and the other end of the communicating pipe is connected with a water supply pipeline between the first electric regulating valve and the first check valve;

when the unit normally works, the first manual flange ball valve, the second manual flange ball valve, the third manual flange ball valve and the fourth manual flange ball valve are opened, the first electric regulating valve and the first electric switch valve are opened, and the first check valve, the second filter valve, the pressure reducing valve and the opening and closing valve are opened;

when the unit is overhauled, the first manual flange ball valve, the second manual flange ball valve, the third manual flange ball valve and the fourth manual flange ball valve are closed;

when the unit is powered off, the first electric regulating valve, the first electric switch valve, the first check valve and the opening and closing valve are automatically closed;

when the unit is in failure and power failure, the first check valve and the opening and closing valve are automatically closed.

Furthermore, a first pressure gauge is arranged on a pipeline of the water supply pipeline between the first filter valve and the circulating pump, and a first thermometer is arranged on a pipeline of the water supply pipeline between the first electric regulating valve and the first check valve; and a second thermometer is arranged on a pipeline between the second filter valve and the pressure reducing valve of the water return pipeline, and a second pressure gauge is arranged on a pipeline between the first electric switch valve and the fourth manual flange ball valve of the water return pipeline.

Furthermore, the water supply pipeline and the water return pipeline are in a concave shape, and a plurality of flexible connecting pipes and bent pipes are arranged on the water supply pipeline and the water return pipeline.

Furthermore, first manual flange ball valve and external pipeline pass through hose connection pipe and return bend intercommunication, and the manual flange ball valve of second passes through hose connection pipe and return bend intercommunication with external pipeline, and the manual flange ball valve of third passes through hose connection pipe and return bend intercommunication with external pipeline, and the manual flange ball valve of fourth passes through hose connection pipe and return bend intercommunication with external pipeline.

Further, the first filter valve is communicated with the circulating pump through a bent pipe and a soft connecting pipe; the circulating pump is communicated with the first electromagnetic switch valve through a flexible connecting pipe and a reducer pipe; the first electromagnetic switch valve is communicated with the first check valve through a bent pipe; the second filter valve is communicated with the pressure reducing valve through a bent pipe.

The technical effects of the utility model are as follows: compared with the existing product, the product has the advantages of chemical control of heat network balance, reduction of heat energy loss, cost saving and stable operation. In order to avoid the limitation of a three-phase power supply, the motor set has the function of normal operation of a single-phase power supply. In order to play a self anti-freezing function of the unit, the periphery, the top and the bottom of the unit are insulated by aluminum silicate, and the unit is insulated by waste heat emitted by the unit.

This unit is installed in the air for box structure majority, and for easy maintenance, the electric folding door mechanism of taking automatic rising function is installed to unit box both sides, and usable cell-phone control, for maintainer's safety, protector is installed to electric folding door mechanism, as manual maintenance operation platform.

The unit is mainly used for the heating problem that the heating pressurizing unit is arranged at the highest position of the large central heating unit for supplying heat because the heights of partial residents exceed the range in the heating unit area of the large central heating unit so as to meet the requirement of the residents with the redundant area in the high area.

The unit can be connected through the Bluetooth by using the mobile phone and controlled by using control software installed on the mobile phone, and the software can also set alarm parameters, and can automatically alarm if various set indexes of the unit are out of order and exceed standards. Meanwhile, the unit also has the function of transmitting data back in real time, when the unit runs, the pipeline pressure and the supply and return water temperature can be transmitted to the master control room through the unit transmission system, the master control room can be monitored in real time, and the central control room can remotely control the unit through a control system arranged in the unit, so that the unattended function is achieved.

The advantage of this product lies in, this heat supply pressurization unit realizes control through the control system on the installation box, installs the electronic component in the installation box and mutually supports with pressure transmitter, the temperature sensor of installation on the unit, and the purpose that each part normal operating of control unit reaches the heat supply. The unit does not need a heat exchanger to isolate pressure, reduces the input cost, and the high area and the low area share one pipe network, and the pipe network is uniformly controlled by a control system, so that the operation management is convenient, the hydraulic balance of the pipe network is facilitated, and the reasonable utilization of heat energy is ensured.

The heat supply and pressurization unit is a novel device with pressurization and pressure relief functions. The mobile phone-based remote control unit has the main characteristics of small volume, convenience in installation, capability of being controlled by a mobile phone, and the function of returning data to a centralized control room for unified control, and can be installed in the air to reduce the occupied area.

Drawings

FIG. 1 is a perspective view of a press assembly of an embodiment;

FIG. 2 is a schematic structural view of a water supply line in the embodiment;

FIG. 3 is a schematic structural diagram of a water return pipeline in the embodiment;

FIG. 4 is a perspective view of the mounting case of the embodiment;

FIG. 5 is a schematic view of the connection between the lower folding door and the installation box in the embodiment;

FIG. 6 is a circuit diagram of an overcurrent protection circuit board in an embodiment;

FIG. 7 is a control circuit diagram of a driving motor in the embodiment;

FIG. 8 is a circuit diagram of the connection between the driving motor and the PLC in the embodiment.

Reference numerals: 1. a water supply line; 11. a first manual flanged ball valve; 12. a first filter valve; 13. a circulation pump; 14. a first electric control valve; 15. a first check valve; 16. a second manual flange ball valve; 17. a first pressure transmitter; 18. a first temperature sensor; 19. a second pressure transmitter; 2. a water return pipeline; 21. a third manual flanged ball valve; 22. a second filter valve; 23. a pressure reducing valve; 24. opening and closing a valve; 25. a first electrically operated on-off valve; 26. a fourth manual flanged ball valve; 27. a third pressure transmitter; 28. a fourth pressure transmitter; 29. a second temperature sensor; 3. a communicating pipe; 4. installing a box body; 41. a folding door assembly; 42. a drive motor; 43. a drive rack; 44. a buffer spring; 45. an access door; 46. a control side door; 47. an exhaust fan; 5. a first pressure gauge; 51. a second pressure gauge; 52. a flexible connection pipe; 53. bending the pipe; 54. a first thermometer; 55. a second thermometer; 6. a lower folding door; 61. spacing folding rod.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.

Examples

As shown in fig. 1-8, a heat supply and pressurization unit includes an installation box 4, and a pipeline structure for the heat supply and pressurization unit is arranged in the installation box 4, and includes a water supply pipeline 1, a water return pipeline 2, and a communicating pipe 3.

A first manual flange ball valve 11, a first filter valve 12, a circulating pump 13, a first electric regulating valve 14, a first check valve 15 and a second manual flange ball valve 16 are sequentially arranged on the water supply pipeline 1 along the water flow direction; a first pressure transmitter 17 and a first temperature sensor 18 are arranged on a pipeline of the water supply pipeline 1 between the first filter valve 12 and the circulating pump 13; the water supply pipeline 1 is provided with a second pressure transmitter 19 on a pipeline between the first electric regulating valve 14 and the first check valve 15; the circulation pump 13 is preferably a variable frequency circulation water pump.

The water return pipeline 2 is sequentially provided with a third manual flange ball valve 21, a second filter valve 22, a pressure reducing valve 23, an opening and closing valve 24, a first electric switch valve 25 and a fourth manual flange ball valve 26 along the water flow direction; a third pressure transmitter 27 is arranged on a pipeline of the water return pipeline 2 between the second filter valve 22 and the pressure reducing valve 23; a second temperature sensor 29 and a fourth pressure transmitter 28 are arranged on a pipeline of the water return pipeline 2 between the first electric switch valve 25 and the fourth manual flange ball valve 26;

one end of the communicating pipe 3 is connected with an on-off valve 24 on the water return pipeline 2, and the other end of the communicating pipe 3 is connected with the water supply pipeline 1 between the first electric regulating valve 14 and the first check valve 15;

circulating pump 13, first electrical control valve 14, first pressure transmitter 17, second pressure transmitter 19, first temperature sensor 18, second temperature sensor 29, first electrical switch valve 25, third pressure transmitter 27, fourth pressure transmitter 28 all are connected with long-range total accuse room through control system, or circulating pump 13, first electrical control valve 14, first pressure transmitter 17, second pressure transmitter 19, first temperature sensor 18, second temperature sensor 29, first electrical switch valve 25, third pressure transmitter 27, fourth pressure transmitter 28 is connected with the APP of cell-phone through the bluetooth module in the control system.

When the unit normally works, the first manual flange ball valve 11, the second manual flange ball valve 16, the third manual flange ball valve 21 and the fourth manual flange ball valve 26 are opened, the first electric regulating valve 14 and the first electric switch valve 25 are opened, and the first check valve 15, the second filter valve 22, the pressure reducing valve 23 and the opening and closing valve 24 are opened;

when the unit is overhauled, the first manual flange ball valve 11, the second manual flange ball valve 16, the third manual flange ball valve 21 and the fourth manual flange ball valve 26 are closed;

when the unit is powered off, the first electric regulating valve 14, the first electric switch valve 25, the first check valve 15 and the opening and closing valve 24 are automatically closed;

when the unit is in failure or power failure, the first check valve 15 and the open/close valve 24 are automatically closed.

Rivers are through 13 postpressurizations of circulating pump for the eminence moisturizing, and the setting of communicating pipe 3 for the on-off valve 24 of return water pipeline 2 is closed, and the pressure value of supply channel 1 is reached to the regional water and return water pipeline 2 pressure of pressure boost after, and on-off valve 24 is automatic to be opened, and on-off valve 24 primary function is the regional water of guaranteeing the pressure boost. The first filtering valve 12 and the second filtering valve 22 are arranged to prevent impurities in the water flow from entering the water supply pipeline 1 and the water return pipeline 2 of the unit.

The pressure reducing valve 23 is used for reducing the return water pressure of the return water pipeline 2 and preventing return water from directly entering the downstream of the original pipe network and being in overpressure, and the pressure reducing valve 23 is adjusted manually and then is in a normally open state.

The installation box body 4 is provided with an electric folding door mechanism, and preferably, the front side and the rear side of the installation box body 4 are provided with the electric folding door mechanisms. The electric folding door mechanism comprises a folding door component 41, a driving motor 42, a transmission gear and a transmission rack 43; one end of the folding door component 41 is slidably arranged in a limiting track on the installation box body 4, and the other end of the folding door component 41 is hinged on the installation box body 4; driving motor 42 installs on folding door subassembly 41, and drive gear meshes with driving rack 43 mutually, and driving rack 43 is parallel with spacing track, and driving motor 42 drive gear reciprocating motion realizes folding and the expansion of folding door subassembly 41 on driving rack 43, and driving motor 42 with through control system with long-range total accuse room be connected, or driving motor 42 is connected with the APP of cell-phone through the bluetooth module in the control system.

The folding door assembly 41 is provided with a transmission shaft, two ends of the transmission shaft are provided with transmission gears, the transmission gear at one end of the transmission shaft is meshed with the transmission rack 43, and the transmission gear at the other end of the transmission shaft is meshed and connected with the motor gear of the driving motor 42.

The driving motor 42 is hinged on the folding door assembly 41 through an elastic rotating structure, the elastic rotating structure comprises a hinge and a buffer piece, one side of the hinge is fixed on the folding door assembly 41, the other side of the hinge is fixedly connected with the driving motor 42, one end of the buffer piece is fixedly connected with the driving motor 42, and the other end of the buffer piece is fixed on the folding door assembly 41; in a natural state, the driving motor 42 is in transmission connection with the transmission gear; when the driving motor 42 is rotated, the driving motor 42 is separated from the transmission gear, the buffer member is stretched, and after the external force is removed, the buffer member pushes the driving motor 42 to rotate until the driving motor 42 is in transmission connection with the transmission gear.

When the electric folding door mechanism breaks down, the maintainer rotates the driving motor 42 to separate the driving motor 42 from the transmission gear, and the folding door component 41 of the electric folding door mechanism can automatically descend and fold under the action of gravity, so that the maintainer can conveniently overhaul.

A travel switch is arranged on the mounting box body 4 and is connected with the driving motor 42; when the folding door assembly 41 is completely unfolded and completely closed, the folding door assembly 41 abuts against the travel switch, and the driving motor 42 stops working; when the folding door assembly 41 is between fully extended and fully closed, the folding door assembly 41 is disengaged from the travel switch and the drive motor 42 is operating normally.

That is, when the folding door assembly 41 is lifted to the top to be unfolded and closed tightly, the folding door assembly 41 abuts against the travel switch at the top, so that the driving motor 42 is automatically turned off; when the folding door assembly 41 descends to the bottom folding, the folding door assembly 41 abuts against a travel switch of the bottom, so that the driving motor 42 is automatically turned off.

The driving rack 43 is parallel to the vertical direction, and the folding door assembly 41 is connected with the installation box 4 through a buffer. The upper end of the folding door component 41 is arranged in the limiting track in a sliding mode, and the lower end of the folding door component 41 is hinged to the installation box body 4.

The buffer member may be a buffer spring 44, an upper end of the buffer spring 44 is connected to the installation case 4 through an iron chain, and a lower end of the buffer spring 44 is connected to the folding door assembly 41. During the folding process of the folding door assembly 41, the buffer spring 44 is stretched, which plays a role of speed reduction and buffering for the folding process of the folding door assembly 41, and avoids the situation that the driving motor 42 is burnt out due to the overspeed of the driving motor 42 when the falling speed of the folding door assembly 41 is too high.

Overall, the buffer spring 44 functions as: when the folding door assembly 41 descends and folds, the buffer spring 44 is stretched, energy is charged into the buffer spring 44, when the folding door assembly 41 ascends and unfolds, the buffer spring 44 contracts, energy is released, and the driving motor 42 is prevented from overspeeding when the folding door assembly 41 descends and the driving motor 42 is overloaded when the folding door assembly 41 ascends, so that the power of the driving motor 42 is reduced, and cost is saved.

In the unfolding process of the folding door assembly 41, the stretched buffer spring 44 has an upward pulling force on the folding door assembly 41, and cooperates with the driving motor 42 to pull the folding door assembly 41 upwards for unfolding, so that the load of the driving motor 42 is reduced, and the driving motor 42 is prevented from being overloaded and burnt.

The installation box body 4 is provided with an access door 45 which can enter the interior of the installation box body 4, so that manual access is facilitated.

The water supply pipeline 1 and the water return pipeline 2 are in a concave shape, so that the space is saved, and the telescopic compensation effect of the pipelines is achieved. Specifically, the water supply pipeline 1 and the water return pipeline 2 are both provided with a plurality of rubber soft connecting pipes 52 and bent pipes 53; the first manual flange ball valve 11 is communicated with an external pipeline through a flexible connecting pipe 52 and an elbow 53, the second manual flange ball valve 16 is communicated with the external pipeline through a flexible connecting pipe 52 and an elbow 53, the third manual flange ball valve 21 is communicated with the external pipeline through a flexible connecting pipe 52 and an elbow 53, and the fourth manual flange ball valve 26 is communicated with the external pipeline through a flexible connecting pipe 52 and an elbow 53.

The first filter valve 12 is communicated with the circulating pump 13 through a bent pipe 53 and a soft connecting pipe 52; the circulating pump 13 is communicated with the first electric regulating valve 14 through a flexible connecting pipe 52 and a reducer pipe; the first electrical regulator valve 14 and the first check valve 15 communicate through a bent pipe 53. The function of the hose 52 is to prevent resonance and to prevent contraction at the start and stop of the circulation pump 13. Gaps between the water supply pipeline 1 and the water return pipeline 2 and the wall surface of the installation box body 4 are plugged through a silica gel plate, and the shock absorption effect is achieved.

A first pressure gauge 5 is arranged on a pipeline of the water supply pipeline 1 between the first filter valve 12 and the circulating pump 13, and a first thermometer 54 is arranged on a pipeline of the water supply pipeline 1 between the first electric regulating valve 14 and the first check valve 15; a second thermometer 55 is arranged on a pipeline of the water return pipeline 2 between the second filter valve 22 and the pressure reducing valve 23, and a second pressure gauge 51 is arranged on a pipeline of the water return pipeline 2 between the first electric switch valve 25 and the fourth manual flange ball valve 26. When the unit is overhauled, the pipeline pressure and the temperature at the corresponding positions can be conveniently observed.

Polyurethane heat-insulating materials are filled in the closed interlayers on the periphery of the installation box body 4, and aluminum silicate heat-insulating cotton materials are installed on the bottom plate of the box body and the interlayers of the bottom plate. The waste heat emitted by the unit is utilized to carry out self heat preservation.

A control cabinet for installing a control system is arranged in the installation box body 4, and a control side door 46 for opening and closing the control cabinet is arranged outside the installation box body 4.

The control system comprises a Bluetooth module interconnected with the mobile phone and is controlled through APP control software installed in the mobile phone. The software can also set alarm parameters, and if the unit fails, each set index exceeds the standard, the software can automatically alarm; meanwhile, the unit also has the function of transmitting data back in real time, when the unit runs, the pipeline pressure and the water supply and return temperature can be transmitted to the master control room through the unit transmission system, the master control room can carry out real-time monitoring, and the master control room can remotely control the unit through the control system, so that the unattended function is achieved.

When the unit needs to be overhauled, an overhaul person can control the opening and closing of the electric folding door mechanism through control software installed in the mobile phone, and the overhaul person can conveniently enter the electric folding door mechanism.

Set up exhaust fan 47 on the installation box 4, exhaust fan 47 is connected with control system, and when the high temperature in the installation box 4, reduce the temperature in the installation box 4 through exhaust fan 47, make equipment normal operation.

The folding door component 41 comprises an upper folding door, a lower folding door 6 and a limiting folding rod 61, the lower end of the upper folding door is hinged with the upper end of the lower folding door 6, one end of the limiting folding rod 61 is connected with the middle lower part of the installation box body 4, and the other end of the limiting folding rod 61 is connected with the side part of the lower folding door 6. When the folding door assembly 41 is folded, the limiting folding rod 61 is gradually unfolded to apply pulling force to the lower folding door 6, so that the movement speed of the folding door assembly 41 is reduced; when the folding door assembly 41 is folded to the horizontal position, the limiting folding rod 61 is completely inclined and unfolded, so that the folding door assembly 41 is limited to the horizontal position; the check folding bar 61 is completely folded at the side of the folding door assembly 41 when the folding door assembly 41 is in the unfolded state.

The control system comprises a display screen, a control button, a driving circuit board, a PLC, a circuit breaker, an auxiliary power supply and a driving motor control board. The display screen, the control button, the driving circuit board, the circuit breaker, the auxiliary power supply and the driving motor control board are all connected with the PLC, the display screen is used for displaying data transmitted by all parts, so that a worker can visually know the operating parameters of the equipment, and the control button is used for controlling a switch for switching between remote control and local control, an emergency stop button and a micro unit maintenance platform circuit control button; the driving circuit board is used for driving each electronic switch and single-path protection in the control system; the PLC is a program headquarter, automatically controls equipment and transmits input and output of data to each component; the breaker is used for on-off control of a power supply, and plays roles of short-circuit protection and the like; the auxiliary power supply is used for supplying power to the display screen and the driving circuit board.

The control unit is arranged on the control panel of the driving motor, the execution unit comprises an overcurrent protection circuit board, the execution unit comprises an execution relay, the execution relay is connected with a limit switch, the execution relay is connected with the overcurrent protection circuit board, the overcurrent protection circuit board is connected with the driving motor, the overcurrent protection circuit board is directly powered for the overcurrent protection circuit board through the driving motor, an auxiliary power supply is saved, electric energy is saved, the failure rate is reduced, and the overcurrent protection effect is achieved on the driving motor.

The working principle of the heat supply pressurizing unit is as follows: heat source hot water gets into heat supply pressurization unit through supply line 1, pressurize through the frequency conversion circulating water pump who installs in the unit and cooperate jointly with the on-off valve 24 of return water pipeline 2 installation, carry hot water to the heating device of user in, when all user heating device moisturizing finishes, supply, when return water pipeline pressure balance, the on-off valve 24 of installation is automatic to be opened on the return water pipeline 2, return water pressure reduces to the safety pressure after under the relief pressure valve 23 effect, merge into in the downstream pipe network, begin normal heat supply.

The flange ball valve is all installed to heat supply pressure unit confession, return water pipe both sides, and valve opening state under the normal condition is in order to prevent the interior water refluence of pipeline when unit spare part breaks down, and convenient the maintenance simultaneously closes the flange ball valve. Install automatic check valve and the electrical control valve on water supply pipe, close immediately under power failure or proruption state, protection unit and low reaches heating device's safety, but normal during operation electrical control valve regulating pipeline hot water flow utilizes automatic check valve and electrical control valve to play duplicate protection's effect.

The automatic opening and closing valve 24 and the electric switch valve are installed on the water return pipeline, the electric switch valve has a power failure closing function, the situation that after power failure occurs, water in the pipeline of the heat supply and pressurization unit flows into a plate area supplied by the large central heat supply unit to cause overlarge pressure to damage the pipeline of each household is prevented, the automatic opening and closing valve 24 is in a pressure difference control mode, water flow is automatically cut off when pressure difference occurs due to power failure, and the automatic opening and closing valve 24 and the electric switch valve are used for achieving a double protection function.

The above description has been made in detail only for the preferred embodiment of the present invention, but the present invention is not limited to the above embodiment, and various changes can be made without departing from the spirit of the present invention within the knowledge scope of those skilled in the art, and all such changes are intended to be encompassed by the present invention.

Claims

1. A pipeline structure for a heating and pressurizing unit is characterized by comprising a water supply pipeline, a water return pipeline and a communicating pipe;

2. The piping structure for a heating and pressurizing unit as claimed in claim 1, wherein a first pressure gauge is provided on a pipe of the water supply line between the first filtering valve and the circulating pump, and a first temperature gauge is provided on a pipe of the water supply line between the first electric regulating valve and the first check valve; and a second thermometer is arranged on a pipeline between the second filter valve and the pressure reducing valve of the water return pipeline, and a second pressure gauge is arranged on a pipeline between the first electric switch valve and the fourth manual flange ball valve of the water return pipeline.

3. The piping structure of claim 1, wherein the water supply line and the water return line are formed in a concave shape, and a plurality of flexible connection pipes and bent pipes are provided on each of the water supply line and the water return line.

4. The piping structure for a heating and pressurizing unit as claimed in claim 3, wherein the first manual flange ball valve is communicated with the external pipe through the flexible joint pipe and the elbow, the second manual flange ball valve is communicated with the external pipe through the flexible joint pipe and the elbow, the third manual flange ball valve is communicated with the external pipe through the flexible joint pipe and the elbow, and the fourth manual flange ball valve is communicated with the external pipe through the flexible joint pipe and the elbow.

5. The piping structure for a heating and pressurizing unit according to claim 3 or 4, wherein the first filtering valve and the circulating pump are communicated through a bent pipe and a flexible connecting pipe; the circulating pump is communicated with the first electromagnetic switch valve through a flexible connecting pipe and a reducer pipe; the first electromagnetic switch valve is communicated with the first check valve through a bent pipe; the second filter valve is communicated with the pressure reducing valve through a bent pipe.