JPS592814B2 - fluid heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluid heater for heating a fluid loaded with a high voltage, such as paint for electrostatic coating.

When fluids such as paints for electrostatic coating become low in temperature and high in viscosity, they cannot be pumped efficiently, so it is desirable to install a heater in the middle of the pressure pipe. Since high voltage is applied to electro-coating paint, if you heat it as it is,
Sparks occur and the eyelids are in danger.

Therefore, when heating a conductive fluid loaded with a high voltage, the conventional methods are to heat a highly insulating fluid separately and pump it, and exchange heat between the fluids. The conventional method is to operate electric heaters of the same potential via an insulating transformer, and use the electric heaters to heat a fluid loaded with a high voltage.

However, in the former method, a passage for the fluid to be pumped must be formed in order to be pumped, resulting in a complicated system and poor thermal efficiency.

Furthermore, the latter method requires an expensive isolation transformer, and requires sufficient care in its maintenance, inspection, and handling.

The present invention solves the above-mentioned problems, and its purpose is to provide a fluid heater that has a simple configuration and can efficiently heat a fluid to be heated that is loaded with a high voltage without impairing insulation properties. be.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of a fluid heater according to the present invention will be described below with reference to embodiments thereof and drawings.

In FIG. 1, reference numeral 1 denotes a heating section body, inside of which is provided a space 3 for accommodating a small amount of insulating working fluid 2. An electric heater 4 is provided as a heat source, and furthermore, the heating section main body 1 is grounded.

5 is a detector for detecting the vapor temperature or pressure of the working fluid 2;

The working fluid 2 is required to be a material that does not decompose at high temperatures and has high insulation properties.

In the embodiment, the electric heater 4 is embedded and installed in the heating unit main body 1, but the electric heater 4 is not limited to this, and may be placed in the space 3 of the main body 1, or even outside the main body 1. It's good.

A hollow insulator 6 is attached to the opening edge of the heating section main body 1 via a packing 7.

The total length of the insulator 6 is determined depending on the load voltage of the fluid to be heated.

Reference numeral 8 denotes a fusible plug which, when the heating temperature exceeds a specified range, melts and releases a steam working fluid to the outside in order to lower the internal pressure of the main body 1.

A heat dissipation section main body 9 is attached to the insulator 6 via a packing 10, and the insulator 6 at the intermediate portion of the heating section main body 1 and the heat dissipation section main body 9 form a closed container in which the working fluid 2 is sealed under reduced pressure. There is.

A hole 11 for returning the condensed working fluid 2 to the heating section main body 1 side and a hole 11 for passing the working fluid 2 in the form of steam are provided at the bottom of the heat dissipating section main body 9.

Note that although the hole 11 is provided, the hole 11 is not necessarily required in a case where the liquefied working fluid 2 is returned smoothly.

As is clear from FIGS. 1 and 2, both opening ends of the heat dissipating section main body 9 are tightly closed by the closing plates 12 and 13.
The closing plates 12 and 13 support heat transfer tubes 14 as a plurality of fluid passages passing through the heat radiating section main body 9.

A heated fluid loaded with a high voltage of 10 to 100 KVO flows inside the heat transfer tube 14 .

Here, the heated fluid loaded with this high voltage is:
Electrostatic paint is used.

Closing plates 12, 13Vc (d cavity 15 is provided on the inlet/outlet side of the heat transfer tube 14, a drain hole 16 is provided at the bottom of the cavity 15 of the closing plate 12, and the inside of the cavity 11 of the closing plate 13 is provided with a drain hole 16. A temperature indicator 18 is provided.

Note that the drain hole 16 is normally closed with a drain valve.

24 is a gas vent valve.

Reference numerals 19 and 20 denote end plates, and the end plate 19 is provided with an inlet 21 for the fluid to be heated, and the end plate 20 is provided with an outlet 22.

Hereinafter, the operation of the fluid heater according to the present invention will be explained.

The inside of the closed container is evacuated through the gas vent valve 18, and the highly insulating working fluid 2 is sealed therein.

In this state, the working fluid 2 is heated by the heater 4 and becomes steam.
, passes through the insulator 6 and moves into the heat radiating part body 9 due to the pressure difference between the heat radiating part body 9 and the heating part body 1 .

Then, it condenses on the outer periphery of the heat exchanger tube 14 and releases heat, and the heated fluid flowing inside the heat exchanger tube 14 is heated by the heat.

The condensed working fluid 2 passes through the holes 11 and 11 to the insulator 6.
It returns to the heating section main body 1.

In addition, if the curved metal 23 is inserted into the heat exchanger tube 14, the temperature can be raised uniformly by passing the fluid while swirling, and the heat exchange efficiency can be improved.

As explained above, in the 5M, the intermediate part between one end of the sealed container and the other end of the sealed container is formed of an insulator, and the sealed container is filled with an insulating hydraulic fluid. It has the effect of efficiently heating the heated fluid loaded with voltage without damaging its insulation properties, and it is said to be highly economical as it can heat the fluid without using a full insulation transformer loaded with high voltage. In addition to the secondary effects, since only a small amount of working fluid is needed, there is an effect that the start-up from the start of heating to steady operation can be made faster.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of the present invention. FIG. 2 is a partial left side view of FIG. 1. DESCRIPTION OF SYMBOLS 1... Heating part main body (the other end side of a sealed container), 2... Working fluid, 6... Insulator, 9... Heat radiation part main body (one end side of a sealed container), 14... Transmission heat tube.

Claims (1)

[Claims] 1 A passage for a heated fluid loaded with a high voltage is formed at one end of a closed container, a heat source is provided at the other end, the middle portion of the closed container is formed of an insulator, and a heat source is provided in the closed container. 1. A fluid heater characterized in that an insulating working fluid is sealed which is vaporized by the airtight container and liquefied at one end of the closed container to heat the fluid to be heated loaded with the high voltage.