JPH0244681A - Heater for industrial use and method for monitoring their damage - Google Patents

Abstract

PURPOSE:To prevent a heater main body from having a contact with a liquid to be heated by surrounding a pipe, in which the heater main body is inserted, with another pipe while keeping airtight, forming an intake for gas supply in the latter pipe, and filling the space between the two pipes with a gas by pressure. CONSTITUTION:A nipple 22 is formed in the upper end of an external pipe 20 surrounding an internal pipe 10 in which a heater main body 15 is inserted and compressed air is filled in the gap 24 between the two pipes by pressure. With this structure, when the external pipe 20 is corroded with a chemical and has holes, the compressed air leaks from the holes resulting the decrease of the pressure of a tube 9. Then, a pressure sensor 7 detects the pressure decrease and let a buzzer operate and make an alarm signal, thus troubles can be found before the heater main body 15 is contacted directly with a chemical in a tank and polluted with the chemical.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention prevents the heater body, which is inserted into a pipe so as to be immersed in a liquid tank such as a chemical liquid, from contaminating the liquid due to damage. The present invention relates to an industrial heater with a structure obtained and a method for monitoring damage thereof.

(Prior Art and Problems to be Solved by the Invention) The pipes of conventional industrial heaters of this kind are made of acid-resistant Teflon or acid-resistant quartz that can withstand higher temperatures.

However, if such pipes are attacked by chemicals or
Alternatively, if the heater body, such as a nichrome wire, is damaged during heating due to mechanical shock, the chemical may become contaminated, and if particularly high purity is required, the entire liquid must be replaced. Despite this situation, there has been no conventional method for preventing the heater body from being exposed to the liquid.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an industrial heater and a method for monitoring damage thereof, which prevents the heater body from being exposed to liquid due to pipe breakage during heating in a liquid tank.

(Means for Solving the Problems) In order to achieve this object, the present invention surrounds the heater storage pipe with another pipe in an airtight state with a space provided, and also supplies gas to the space in this other pipe. A gas supply port for pressure injection was provided.

When monitoring damage to this industrial heater, a pressurized gas source is connected to the gas supply port to inject gas at a predetermined pressure into the double pipe space, and the predetermined pressure in this space is continuously measured using a pressure sensor. When the pressure sensor detects a drop in pressure from a predetermined pressure, an alarm is generated.

(Function) During failure monitoring, if the pressurized gas leaks, especially due to a failure in the outer pipe, a pressure drop will occur in the space. As a result, the pressure sensor detects a decrease in pressure from the predetermined pressure, and an alarm is generated.

Embodiments of the Invention FIG. 1 shows an industrial heater and damage monitoring accessory according to one embodiment of the invention.

In the figure, l is an industrial heater equipped with an L-shaped quartz inner tube lO and outer tube 20, each having a height H of 251]+m and a horizontal length of 380 mm. As usual, a bobbin 11 is inserted into the horizontal portion of the inner tube IO, and the heater body 15 is wound as a double coil.

The bobbin 11 is formed by winding a solid linear body 11b, which is also made of quartz and has a substantially circular cross section, around the circumferential surface of a tube 11a made of quartz, or by spirally winding it in a heat-softened state, and spacers 12 on both sides. is arranged at the center of the inner tube 10. As the heater body 15, a nichrome wire coil 15a is further spirally wound in the gap between the linear bodies 11b (see FIG. 2).

From the connector 2 there is a conductor 3 surrounded by an insulating sleeve 4.
3 a is introduced and guided along the vertical portion of the inner tube 10 , and one of the conductive wires 3 is connected to one end of the heater body 15 . The other end of the heater body is connected to a return conductor rod 16 inserted into the tube 11a through a terminal 17. The other conductive wire 3a is connected to the other end of this conductor rod.

According to the invention, the inner tube 1O is surrounded by an outer tube 20, also made of quartz, with a gap 24 at a small distance.

Reference numeral 21 denotes a spacer that partially protrudes from the outer circumferential surface of the inner tube 10 and defines the distance between them. This outer tube airtightly surrounds the inner tube IO, and gas is circulated through the gap 24 from its upper end to its end. A nipple 22 is provided at the upper end of the outer tube 20 to which pressurized gas is supplied.

Next, a damage monitoring method using this industrial heater 1 will be explained.

With all of the horizontal part and part of the vertical part of the industrial heater 1 immersed in the tank, the chemical heating in the premises is performed by supplying power from the connector 2 to the heater body 15 through the conductive wire 3.3a.

According to the present invention, compressed air is supplied to the nipple 22 from the compressor 8 through the tube 9, for example, and the compressed air is pressurized into the gap 24 of the double pipe, and the pressure drop is detected in the compressed air supply path. A pressure sensor 7 is attached thereto, and a buzzer 6 is attached as an alarm means to respond to the detection signal of this sensor.

As a result, the gap 24 is maintained under a predetermined pressure.
In g, if the outer tube 20 is attacked by chemicals and has a hole, compressed air leaks through the hole, causing the pressure in the tube 9 to drop. Therefore, the pressure sensor 7 detects the pressure drop and activates the buzzer 6 to issue an alarm. In other words, an abnormality can be detected before the heater body 15 is contaminated by direct contact with chemicals in the tank, and by replacing or repairing the industrial heater l at this stage, it is possible to prevent chemical contamination. can.

The same is true when the outer tube 20 is mechanically damaged, and even when the inner tube 10 is broken for some reason, a pressure drop occurs through the inner tube, and an abnormality is similarly detected.

The present invention is not limited to the L-shaped heater of the above-described embodiment, but can be applied to various types of heaters, such as horizontal, circular or U-shaped heaters, or simply linear heaters. Also,
The heater body is also not limited to the double coil type. Furthermore, the gas to be pressurized may not be air depending on the case, and the alarm means may be other than a buzzer.

(Effects of the Invention) As described above, the double pipe structure industrial heater in which pressurized gas is injected into the gap of the present invention prevents contact with the liquid to be heated due to breakage of the pipe surrounding the heater body. Ru.

Therefore, the reliability of the heating operation is improved, and the situation where the liquid needs to be replaced can be reliably avoided.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of an industrial heater according to an embodiment of the present invention, and a diagram showing a schematic configuration of an attached device thereof, and FIG. 2 is a diagram showing the structure of a coil body. DESCRIPTION OF SYMBOLS 10...Inner tube, 11...Bobbin, 15...Heater main body, 20...Outer tube, 22...Nipple.

Claims (1)

[Claims] 1) In an industrial heater in which the heater body is inserted into a pipe so as to be immersed in a liquid tank and is supplied with power from outside the liquid tank, the pipe is separated by a space. An industrial heater characterized in that the heater is surrounded in an airtight manner by another pipe, and the other pipe is provided with a gas supply port for pressurizing gas into the space. 2) A pressurized gas source is connected to the gas supply port of the industrial heater according to claim 1 to pressurize gas at a predetermined pressure into the space of the industrial heater, and the predetermined pressure in this space is detected by a pressure sensor. A method for monitoring damage to an industrial heater, characterized in that: the pressure sensor continuously monitors the pressure at a pressure lower than the predetermined pressure, and generates an alarm when the pressure sensor detects a decrease in pressure from the predetermined pressure.