A leak-proof electric heater suitable for hazardous environments

Abstract

This invention relates to the field of electric heater technology, and particularly to a leak-proof electric heater suitable for hazardous environments. It includes: electric heating tubes, employing a U-shaped structure and arranged in plurality of them; wherein, each electric heating tube comprises: an electric heating element, metallurgical powder, and an outer tube; the outer tube is sleeved around the electric heating element, and the space between the electric heating element and the outer tube includes the metallurgical powder, which is a porous medium layer formed after sintering at 1050℃; a pressure vessel, in which a plurality of the electric heating tubes are linearly arrayed and installed. This invention fills a gap in the application of heating high-risk media, and is particularly suitable for heating some highly toxic media. It is a leak-proof electric heater that provides an early warning function for heating high-risk media.

Description

Technical Field

[0001] This invention relates to the field of electric heater technology, and in particular to a leak-proof electric heater suitable for hazardous environments. Background Technology

[0002] Traditional circulating electric heaters typically use direct welding between the heating element and the flange (or a connection via an intermediate sleeve). If the heating element leaks due to corrosion from a hazardous medium or other reasons, the leaked medium will be transferred through the magnesium oxide powder (which is also porous) inside the element to the explosion-proof junction box. Since the junction box is an energized environment, a short circuit between the electrodes could lead to unimaginable accidents. In other words, traditional equipment provides no warning devices or warning time for heating such hazardous media. Summary of the Invention

[0003] The purpose of this invention is to provide a leak-proof electric heater suitable for hazardous environments, filling the gap in applications for heating highly hazardous media. It is particularly suitable for heating some highly toxic media and is a leak-proof electric heater that provides an early warning function for heating highly hazardous media.

[0004] To solve the above-mentioned technical problems, the present invention provides a leak-proof electric heater suitable for hazardous environments, comprising:

[0005] The electric heating element has a U-shaped structure and is arranged in several parts;

[0006] The electric heating tube includes: an electric heating tube, metal metallurgical powder, and an outer tube; the outer tube is sleeved on the outside of the electric heating tube, and the metal metallurgical powder is filled between the electric heating tube and the outer tube. The metal metallurgical powder is a porous medium layer formed after sintering at a high temperature of 1050°C.

[0007] A pressure vessel, wherein a linear array of the aforementioned electric heating tubes is installed inside the pressure vessel.

[0008] Preferably, the heating element, the metallurgical powder, and the outer tube are all connected by high-pressure rolling.

[0009] Preferably, it also includes baffles, which are linearly and alternately arranged inside the pressure vessel, so that its heat exchange zone forms a multi-pass S-shaped flow channel.

[0010] Preferably, the wiring terminal of the electric heating tube is located outside the pressure vessel, and the pressure vessel has an inlet and an outlet at its two ends, respectively.

[0011] Preferably, the end of the pressure vessel near the inlet side also includes a detection chamber mounted via a process flange, on which an electrical detection instrument is installed, which is an electrical contact pressure gauge or a hazardous gas detector.

[0012] Preferably, the detection chamber (5) is pre-filled with a protective gas including but not limited to nitrogen. The pressure of the detection chamber (5) is higher than the working pressure of the hazardous medium being heated. Once the electric heating tube (1) leaks, the pressure of the protective gas in the detection chamber (5) decreases, triggering an alarm on the electric detection instrument (6).

[0013] Preferably, it also includes a junction box, which is installed on the wiring terminal of the electric heating tube and is designed as an explosion-proof structure according to the application.

[0014] Preferably, the junction box also includes a cable inlet.

[0015] Preferably, it also includes a temperature sensor, which is mounted on the electric heating tube.

[0016] Preferably, it also includes a heat dissipation area located between the pressure vessel and the junction box.

[0017] Preferably, the surface heating power of the electric heating tube decreases sequentially from the inlet to the outlet of the pressure vessel.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. This invention adds an outer tube to the traditional heating element. A thin layer of metal powder lies between the outer tube and the traditional heating element. The outer tube, metal powder, and traditional heating element are connected by high-pressure rolling. This heating element undergoes high-temperature sintering at 1050℃, becoming a key component of a leak-proof electric heater for hazardous applications. The sintered metal powder forms a porous medium. This porous medium serves two main functions: firstly, as a heat transfer channel between the traditional heating element and the outer tube; secondly, utilizing its porous nature, in the event of corrosion or damage to the outer tube by a hazardous medium, the medium, especially a gas, will be transferred through the porous gaps in the metal powder to the detection chamber on the heater's process flange. Whether through pressure detection or hazardous gas detection, an alarm is immediately triggered upon detection of a leak. Alternatively, a certain pressure can be pre-pressurized into the detection chamber, for example, pre-filled with nitrogen and maintained above the working pressure of the medium. If the heat exchange outer tube is damaged, the pressure inside the chamber drops, triggering an alarm immediately. This device is particularly suitable for heating hazardous media and is a leak-proof electric heater.

[0020] 2. This invention provides a leak-proof electric heater suitable for hazardous environments, filling the gap in applications for heating highly hazardous media. It is particularly suitable for heating some highly toxic media and is a leak-proof electric heater that provides an early warning function for heating highly hazardous media.

[0021] 3. The variable power design of the electric heating tube in this invention allows the electric heater of this invention to be 1 / 3 the size of the traditional electric heater under the same output power. That is, for devices of the same size, the electric heater of this invention has 3 times the power of the traditional electric heater, which greatly reduces the size. Attached Figure Description

[0022] Figure 1 This is an overall structural diagram of an electric heater suitable for leak prevention in hazardous environments according to the present invention.

[0023] Figure 2 This is a perspective view of the overall structure of an electric heater suitable for leak prevention in hazardous environments according to the present invention.

[0024] Figure 3 This is a cross-sectional view of the overall structure of an electric heater suitable for leak prevention in hazardous environments according to the present invention.

[0025] Figure 4 This is a diagram of an array structure of an electric heating tube suitable for leak prevention in hazardous environments according to the present invention.

[0026] Figure 5 This is a structural diagram of an electric heating tube suitable for leak prevention in hazardous environments according to the present invention.

[0027] In the diagram: 1-Electric heating tube, 11-Electric heating tube, 12-Metallurgical powder, 13-Outer tube, 2-Pressure vessel, 21-Inlet, 22-Outlet, 3-Baffle plate, 4-Process flange plate, 5-Detection chamber, 6-Detection instrument, 7-Junction box, 71-Cable inlet. Detailed Implementation

[0028] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0029] Example 1

[0030] like Figure 1-5As shown, this invention provides a leak-proof electric heater suitable for hazardous environments, comprising: an electric heating tube 1, which adopts a U-shaped structure and has several components arranged thereon; wherein, the electric heating tube 1 includes: an electric heating element 11, metal metallurgical powder 12, and an outer tube 13; the electric heating tube 1 is a conventional electric heating element 11 with metal metallurgical powder 12 filling the space between the outer tube 13. The main functions of the metal metallurgical powder are: 1. to utilize the good thermal conductivity of the metal powder; 2. to become a porous medium after sintering, utilizing the channel characteristics of the porous medium to detect gas leaks. The heat transfer coefficient of metal powder is fully utilized, which is much higher than that of other materials such as magnesium oxide. Specifically, an outer tube 13 is sleeved on the outside of the electric heating tube 11, and a metal metallurgical powder 12 is filled between the electric heating tube 11 and the outer tube 13. The metal metallurgical powder 12 is a porous medium layer formed after high-temperature sintering at 1050℃. The metal metallurgical powder 12 used in the electric heating tube 1 is sintered at a high temperature of 1050℃, so that the metal particles are connected together to form a porous medium. Several electric heating tubes 1 are linearly arrayed and installed inside the pressure vessel 2.

[0031] The heating element 11, metal metallurgical powder 12, and outer tube 13 are all connected by high-pressure rolling. The heating element 11 is sintered at a high temperature of 1050℃ to become the main component of the leak-proof electric heater used in hazardous locations.

[0032] It also includes baffles 3, which are linearly and alternately arranged inside the pressure vessel, forming a multi-pass S-shaped flow path in its heat exchange zone. This is used to switch the flow direction of the fluid and further increase the length of the heat exchange path, thereby improving the heat exchange effect. The wiring terminals of the electric heating tube 1 are located outside the pressure vessel 2. The pressure vessel 2 has an inlet 21 and an outlet 22 at both ends. The fluid enters from the inlet 21, exchanges heat with the electric heating tube 1 and the baffles 3, and then flows out from the outlet 22 of the pressure vessel 2.

[0033] It also includes a junction box 7, which is installed on the wiring terminal of the electric heating tube 1 and is designed as an explosion-proof structure according to the application.

[0034] The junction box 7 also includes a cable inlet 71.

[0035] It also includes a temperature sensor installed on the electric heating element 1. The temperature sensor is used to cut off power when the temperature exceeds the limit, thus activating the protection function of the electric heating element 1. At the same time, it can detect the internal temperature.

[0036] To extend the service life of the cables inside junction box 7, a heat dissipation zone is also included, located between pressure vessel 2 and junction box 7. Additionally, the electric heating element 1 includes a non-heating section, which effectively reduces the temperature of the cables inside junction box 7.

[0037] Example 2

[0038] like Figure 1-5 As shown, based on the above embodiment one, preferably, the end of the pressure vessel 2 near the inlet 21 also includes a detection chamber 5 installed through the process flange plate 4. An electrical detection instrument 6 is installed on the detection chamber 5; the electrical detection instrument 6 is an electrical contact pressure gauge or a hazardous gas detector. The main function of the porous metal medium in the heating tube 11 is, on the one hand, to serve as a heat transfer channel between the heating tube 11 and the outer tube 13 in the traditional sense; on the other hand, utilizing its porous characteristics, in the event that a hazardous medium corrodes or damages the outer tube 13, the medium, especially a gaseous medium, will be transferred to the detection chamber 5 on the heater process flange plate 4 through the porous gaps of the metal powder. Through pressure detection or a hazardous gas detector, once a leak is detected, an alarm is immediately triggered. Alternatively, a certain pressure can be pre-pressurized into the detection chamber 5, for example, pre-filled with nitrogen and maintained above the working pressure of the medium. Once the heat exchange outer tube 13 is damaged, the pressure inside the chamber decreases, and an alarm is immediately triggered. This device is particularly suitable for heating hazardous media and is a leak-proof electric heater.

[0039] Example 3

[0040] like Figure 1-5 As shown, based on the above embodiment 2, the surface heating power of the electric heating tube 1 decreases sequentially from the inlet 21 to the outlet 22 of the pressure vessel 2. The electric heating tube 1 adopts a variable power design technology, that is, a high power density is used where the fluid temperature is low, and a low power density is used where the fluid temperature is high.

[0041] The electric heating element 1 is designed with variable power. Under the same output power, the volume of the electric heater of the present invention is 1 / 3 of that of the traditional electric heater. That is, for the same size device, the electric heater of the present invention has 3 times the power of the traditional electric heater, which greatly reduces the size.

[0042] The above description is merely a description of preferred embodiments of the present invention and is not intended to limit the scope of the present invention in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the claims.

Claims

1. A leak-proof electric heater suitable for hazardous environments, characterized in that, include: An electric heating tube (1) is U-shaped and has several of them arranged. The electric heating tube (1) includes: an electric heating tube (11), metal metallurgical powder (12) and an outer tube (13). The outer tube (13) is sleeved on the outside of the electric heating tube (11), and the metal metallurgical powder (12) is filled between the electric heating tube (11) and the outer tube (13). The metal metallurgical powder (12) is a porous medium layer formed after sintering at a high temperature of 1050°C. A pressure vessel (2) is provided with a linear array of several electric heating tubes (1) installed inside the pressure vessel (2); the two ends of the pressure vessel (2) are respectively provided with an inlet (21) and an outlet (22); The end of the pressure vessel (2) near the inlet (21) also includes a detection chamber (5) installed via a process flange (4), on which an electrical detection instrument (6) is installed, which is an electrical contact pressure gauge or a hazardous gas detector; The detection chamber (5) is pre-filled with a protective gas including nitrogen. The pressure of the detection chamber (5) is higher than the working pressure of the hazardous medium being heated. Once the electric heating tube (1) leaks, the pressure of the protective gas in the detection chamber (5) decreases, triggering an alarm on the electric detection instrument (6).

2. A leak-proof electric heater suitable for hazardous environments as described in claim 1, characterized in that, The electric heating tube (11), the metal metallurgical powder (12), and the outer tube (13) are all connected by high-pressure rolling.

3. A leak-proof electric heater suitable for hazardous environments as described in claim 1, characterized in that, It also includes baffles (3) that are linearly and interlaced inside the pressure vessel (2) to form a multi-pass S-shaped flow channel in the heat exchange zone.

4. A leak-proof electric heater suitable for hazardous environments as described in claim 1, characterized in that, The wiring terminal of the electric heating tube (1) is located outside the pressure vessel (2).

5. A leak-proof electric heater suitable for hazardous environments as described in claim 4, characterized in that, It also includes a junction box (7) which is installed on the wiring terminal of the electric heating tube (1) and is designed as an explosion-proof structure according to the application.

6. A leak-proof electric heater suitable for hazardous environments as described in claim 5, characterized in that, The junction box (7) also includes a cable inlet (71).

7. A leak-proof electric heater suitable for hazardous environments as described in claim 1, characterized in that, It also includes a temperature sensor, which is mounted on the electric heating tube (1).

8. A leak-proof electric heater suitable for hazardous locations as described in claim 5, characterized in that, It also includes a heat dissipation area located between the pressure vessel (2) and the junction box (7).

9. A leak-proof electric heater suitable for hazardous locations as described in any one of claims 1-8, characterized in that, The surface heating power of the electric heating tube (1) decreases sequentially from the inlet (21) to the outlet (22) of the pressure vessel (2).

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