Marine LNG fuel tank differential pressure type liquid level meter liquid phase pipe heating vaporization structure

Abstract

The utility model relates to a liquid phase pipe heating and vaporizing structure of a differential pressure type liquidometer of a marine LNG fuel tank, and belongs to the technical field of marine LNG fuel tanks. The heating vaporization structure comprises a heating pipe, a pneumatic control valve is arranged on the liquidometer liquid phase pipeline, the heating pipe is fixed to the portion, located at the rear end of the pneumatic control valve, of the liquidometer liquid phase pipeline in parallel, one end of the heating pipe is connected with an inlet of the marine hot water tank, and the other end of the heating pipe is connected with an outlet of the marine hot water tank. And a temperature transmitter is arranged in the cold box and is in signal connection with a hot water valve on the marine hot water tank. The starting end of the heating pipe and liquid at the bottom in the LNG fuel tank are arranged at the same height. The liquid level measuring device ensures that the medium is fully vaporized, improves the accuracy and reliability of liquid level measurement, reduces the fault risk, and is suitable for the LNG fuel tank in the low-temperature environment.

Description

Technical Field

[0001] This utility model relates to a differential pressure level gauge liquid phase tube heating and vaporization structure for marine LNG fuel tanks, belonging to the technical field of marine LNG fuel tanks. Background Technology

[0002] To address environmental pollution, the International Maritime Organization (IMO) has imposed stringent requirements on ship emissions, and LNG, as a clean fuel, is widely used. Marine LNG fuel tanks typically employ differential pressure level gauges for level detection. The liquid phase pipe and gas phase pipe extend from the liquid and gas phase spaces of the fuel tank, respectively, and the differential pressure signal is converted into an electrical signal to monitor the level.

[0003] However, in the existing technology, the liquid phase tube of the level gauge is not fully vaporized in the cold box due to poor air convection and low temperature. Especially in winter or high-latitude regions, the level gauge is prone to freezing or inaccurate measurement, which affects the normal execution of shipping plans. Summary of the Invention

[0004] The technical problem to be solved by this utility model is to provide a heating and vaporization structure for the liquid phase tube of a differential pressure level gauge for marine LNG fuel tanks, which ensures that the medium is fully vaporized and improves the accuracy and reliability of the level gauge measurement.

[0005] The technical solution adopted by this utility model to solve the above problems is as follows: a differential pressure level gauge liquid phase pipe heating and vaporization structure for marine LNG fuel tanks, wherein the LNG fuel tank includes an inner shell and an outer shell, the inner shell being disposed inside the outer shell; a gap is left between the outer shell and the inner shell to form a sandwich layer; a cold box is disposed on the outer shell, and a differential pressure level gauge is disposed inside the cold box; a liquid level gauge gas phase pipe and a liquid level gauge liquid phase pipe are disposed in the sandwich layer, one end of the liquid level gauge gas phase pipe and the liquid level gauge liquid phase pipe being respectively connected to the inner shell. The other ends of the vapor phase pipeline and the liquid phase pipeline of the level gauge are respectively connected to a differential pressure level gauge and a level transmitter. The heating vaporization structure includes a heating tube. A pneumatic control valve is provided on the liquid phase pipeline of the level gauge. The heating tube is fixed parallel to the liquid phase pipeline of the level gauge located at the rear end of the pneumatic control valve. One end of the heating tube is connected to the inlet of the marine hot water tank, and the other end of the heating tube is connected to the outlet of the marine hot water tank. A temperature transmitter is provided in the cold box, and the temperature transmitter is signal-connected to the hot water valve on the marine hot water tank.

[0006] The starting end of the heating pipe is at the same height as the liquid at the bottom of the LNG fuel tank.

[0007] The inner shell includes an inner cylinder, with inner end caps provided at both ends of the inner cylinder; the outer shell includes an outer cylinder, with outer end caps provided at both ends of the outer cylinder.

[0008] The heating element is made of small-diameter stainless steel tubing.

[0009] Compared with existing technologies, the advantages of this utility model are as follows: A heating and vaporization structure for the liquid phase pipe of a differential pressure level gauge for marine LNG fuel tanks is provided. A heating pipe is fixed on the liquid phase pipe of the level gauge located at the rear end of the pneumatic control valve and connected to a marine hot water tank, forming a hot water circulation system. This solves the problem of insufficient vaporization caused by low temperatures in the cold tank. This application ensures complete vaporization of the medium, improves the accuracy and reliability of level measurement, reduces the risk of failure, and is suitable for LNG fuel tanks in low-temperature environments. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the installation of a differential pressure level gauge liquid phase tube heating and vaporization structure for a marine LNG fuel tank according to an embodiment of the present invention.

[0011] Figure 2 for Figure 1 Enlarged view of I;

[0012] In the diagram: 1 Inner cylinder, 2 Outer cylinder, 3 Inner end cap, 4 Jacket, 5 Outer end cap, 6 Level gauge gas phase pipeline, 7 Level gauge liquid phase pipeline, 8 Cold box, 9 Pneumatic control valve, 10 Heating tube, 11 Differential pressure level gauge, 12 Temperature transmitter, 13 Level transmitter. Detailed Implementation

[0013] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0014] like Figure 1 , 2As shown in this embodiment, a differential pressure level gauge liquid phase pipe heating and vaporization structure for a marine LNG fuel tank is described. The LNG fuel tank includes an inner shell and an outer shell, with the inner shell located inside the outer shell. A gap is left between the outer shell and the inner shell, forming a sandwich layer 4. A cold box 8 is installed on the outer shell, and a differential pressure level gauge 11 is installed inside the cold box 8. A liquid level gauge gas phase pipe 6 and a liquid level gauge liquid phase pipe 7 are installed in the sandwich layer 4. One end of the liquid level gauge gas phase pipe 6 and the liquid level gauge liquid phase pipe 7 are respectively connected to the inner shell, and the other end of the liquid level gauge gas phase pipe 6 and the liquid level gauge liquid phase pipe 7 are respectively connected to the differential pressure level gauge 11 and the level transmitter 13. The differential pressure level gauge 11 measures the pressure difference between the liquid level gauge gas phase pipe and the liquid level gauge liquid phase pipe to obtain the liquid level height of the LNG fuel tank, that is, to monitor the liquid level in the LNG fuel tank, and then transmits the liquid level data to the control room. A pneumatic control valve 9 is installed on the liquid phase pipeline 7 of the level gauge. A heating pipe 10, arranged parallel to the pneumatic control valve 9, is installed on the liquid phase pipeline of the level gauge downstream of the pneumatic control valve 9. The heating pipe 10 is fixed to the liquid phase pipeline 7 of the level gauge with clamps, ensuring the contact area between the heating pipe and the liquid phase pipeline of the level gauge. One end of the heating pipe 10 is connected to the outlet of the marine hot water tank, and the other end is connected to the inlet of the marine hot water tank, forming a hot water circulation system. Hot water from the marine hot water tank flows into the heating pipe, and the hot water in the heating pipe heats the liquid phase pipeline of the level gauge downstream of the pneumatic control valve. The hot water after heat exchange circulates back into the hot water tank. The cold box is equipped with a temperature transmitter, which is connected to the hot water valve on the marine hot water tank. The temperature transmitter detects the temperature inside the cold box. When the detected temperature is below 10℃, the signal is transmitted to the control room, and the hot water valve is automatically opened, allowing hot water from the hot water tank to flow into the heating pipe and heat the liquid phase pipeline of the level gauge, causing the medium in the liquid phase pipeline of the level gauge to completely vaporize. When the detected temperature is above 10℃, the hot water valve is closed, thus ensuring the measurement accuracy of the differential pressure level gauge.

[0015] In addition to hot water heating, other heating or heat transfer methods can be used, such as electric heating or heating with other media.

[0016] The starting end of the heating tube 10 is set at the same height as the liquid at the bottom of the LNG fuel tank, which makes the measurement more accurate.

[0017] The inner shell includes an inner cylinder 1, with inner end caps 3 at both ends. The outer shell includes an outer cylinder 2, with outer end caps 5 at both ends.

[0018] The heating element mentioned above is made of small-diameter stainless steel tubing.

[0019] A heating element is fixed to the liquid phase pipeline of the level gauge located at the rear end of the pneumatic control valve and connected to a marine hot water tank to form a hot water circulation system, which solves the problem of insufficient vaporization caused by low temperature in the cold box. This application ensures complete vaporization of the medium, improves the accuracy and reliability of level measurement, reduces the risk of failure, and is suitable for LNG fuel tanks in cryogenic environments.

[0020] In addition to the above embodiments, this utility model also includes other implementation methods. All technical solutions formed by equivalent transformation or equivalent substitution should fall within the protection scope of the claims of this utility model.

Claims

1. A differential pressure level gauge liquid phase tube heating and vaporization structure for a marine LNG fuel tank, wherein the LNG fuel tank includes an inner shell and an outer shell, the inner shell being disposed within the outer shell; a gap is left between the outer shell and the inner shell to form a sandwich layer; a cold box is disposed on the outer shell, and a differential pressure level gauge is disposed within the cold box; a liquid level gauge gas phase pipe and a liquid level gauge liquid phase pipe are disposed within the sandwich layer, one end of the liquid level gauge gas phase pipe and the liquid level gauge liquid phase pipe are respectively connected to the inner shell, and the other end of the liquid level gauge gas phase pipe and the liquid level gauge liquid phase pipe are respectively connected to a differential pressure level gauge and a level transmitter, characterized in that: The heating and vaporization structure includes a heating tube. A pneumatic control valve is provided on the liquid phase pipeline of the level gauge. The heating tube is fixed parallel to the liquid phase pipeline of the level gauge located at the rear end of the pneumatic control valve. One end of the heating tube is connected to the inlet of the marine hot water tank, and the other end of the heating tube is connected to the outlet of the marine hot water tank. A temperature transmitter is provided inside the cold box, and the temperature transmitter is signal-connected to the hot water valve on the marine hot water tank.

2. The differential pressure level gauge liquid phase tube heating and vaporization structure for marine LNG fuel tanks according to claim 1, characterized in that: The starting end of the heating pipe is at the same height as the liquid at the bottom of the LNG fuel tank.

3. The differential pressure level gauge liquid phase tube heating and vaporization structure for marine LNG fuel tanks according to claim 1, characterized in that: The inner shell includes an inner cylinder, with inner end caps provided at both ends of the inner cylinder; the outer shell includes an outer cylinder, with outer end caps provided at both ends of the outer cylinder.

4. The liquid phase tube heating and vaporization structure of a differential pressure level gauge for marine LNG fuel tanks according to claim 1, characterized in that: The heating element is made of small-diameter stainless steel tubing.

Images