JP5973199B2 - Steam heating device - Google Patents

Description

The present invention relates to a steam heating apparatus used as a thin hot platen of a corrugating machine used when manufacturing corrugated cardboard or the like.

As a conventional steam heating apparatus, a switching means is interposed on the secondary side of the heat exchanger, that is, an outlet side, and an ejector type vacuum pump and a steam trap are provided. The pump and the steam trap are switched and used.

Japanese Patent No. 2589602

In the above conventional steam heating device, in the case of positive pressure steam, it switches to the condensate self-pressure recovery means, but in the case of a low pressure such that the steam pressure is close to atmospheric pressure, the steam heating device is efficient. There was a problem that could not be heated. This is because the heating efficiency does not increase because the flow of the heating steam is not sufficiently generated inside the steam heating apparatus.

Therefore, the problem to be solved by the present invention is to obtain a steam heating apparatus that can efficiently heat by generating a sufficient flow of steam inside the steam heating apparatus.

In the present invention, a steam supply pipe for heating is connected to the inlet sides of a plurality of heat exchangers via pressure regulating valves, respectively, and the outlet side of the heat exchanger using high-pressure steam is connected to the outlet side of the heat exchanger using low-pressure steam. In addition to being connected to the inlet side, a steam ejector is disposed on the inlet side of the heat exchanger using low-pressure steam, and the suction chamber of the steam ejector communicates with the outlet side of the heat exchanger using low-pressure steam.

  According to the present invention, by connecting the outlet side of the high pressure steam heat exchanger to the inlet side of the low pressure steam heat exchanger, a sufficient steam flow is generated inside the high pressure steam heat exchanger, In addition, a steam ejector is arranged on the inlet side of the heat exchanger using low-pressure steam, and the suction chamber of this steam ejector is connected to the outlet side of the heat exchanger using low-pressure steam, so that the inside of the low-pressure steam heat exchanger Therefore, a steam heating device that generates a sufficient steam flow and efficiently heats the steam can be obtained.

The block diagram which shows the Example of the steam heating apparatus of this invention.

The present invention uses a steam ejector. Any known steam ejector may be used as long as it generates suction force in the suction chamber using steam as a driving fluid.

In this embodiment, an example is shown in which thin heat plates 1 and 2 of a corrugating machine are used as a heat exchanger. In FIG. 1, a high-pressure steam supply pipe 3 connected to the hot platen 1, a low-pressure steam supply pipe 4 connected to the hot platen 2, and a steam ejector 5 arranged in the low-pressure steam supply pipe 4 constitute a steam heating device.

A pressure regulating valve 6 is attached to the high pressure steam supply pipe 3 to the hot platen 1. A steam trap 8 is attached to the outlet pipe 7 of the hot platen 1 and connected to the header tank 9. The outlet pipe 7 is connected to the low-pressure steam supply pipe 4 on the inlet side of the hot platen 2 by a pipe line 10 branched from the outlet pipe 7.

The pressure control valve 11 and the steam ejector 5 are interposed in the low pressure steam supply pipe 4 and connected to the hot platen 2. A steam trap 12 and a bypass valve 13 are arranged in parallel on the outlet side of the hot platen 2 and connected to the header tank 9 by a pipe line 14. A pipe line 15 is attached to the upper left part of the header tank 9 and connected to the suction chamber 16 of the steam ejector 5.

A pipe line 18 is attached to the lower part of the header tank 9 and connected to the liquid inlet 19 of the liquid pumping member 17. A check valve 20 is attached to the pipe line 18. The check valve 20 allows the passage of liquid from the header tank 9 to the liquid pressure feeding member 17 side, and does not allow the passage of liquid in the reverse direction.

A liquid pressure feed line 23 is also connected to the liquid pressure feed port 21 of the liquid pressure feed member 17 via a check valve 22. This check valve 22 allows the liquid to pass only from the liquid pumping member 17 to the liquid pumping line 23 side.

A high-pressure steam inlet 25 connected to a high-pressure steam supply pipe 24 as a pressure-feeding fluid is provided on the liquid pressure-feeding member 17. A high-pressure steam outlet 26 is provided on the left side of the high-pressure steam inlet 25. A high pressure steam discharge pipe 27 is connected to the discharge port 26.

When the float (not shown) arranged inside is located at the lower part, the liquid pressure feeding member 17 is closed in the high-pressure steam inlet 25 while the outlet 26 is opened, and the condensate collected in the header tank 9 However, it flows down into the liquid pumping member 17 through the pipe line 18 and the check valve 20.

  When liquid accumulates in the liquid pressure feeding member 17 and a float (not shown) is positioned at a predetermined upper portion, the discharge port 26 is closed, while the high pressure steam inlet 25 is opened, and the high pressure steam supply pipe 24 opens the high pressure steam. Flows into the liquid pumping member 17, and the liquid accumulated inside is pumped to the liquid pumping destination through the pumping port 21, the check valve 22 and the liquid pumping line 23.

When the liquid is pumped and the liquid level in the liquid pumping member 17 is lowered, the high pressure steam inlet 25 is closed again and the outlet 26 is opened, so that the condensate is pumped from the liquid inlet 19. It flows down inside. By repeating such an operation cycle, the liquid pumping member 17 pumps the condensate in the header tank 9.

  When the steam is supplied to the heating plates 1 and 2 and heated, the high pressure steam is supplied from the high pressure steam supply pipe 3 to the heating plate 1 and the low pressure steam is supplied from the low pressure steam supply pipe 4 to the heating plate 2.

  Condensate generated by heating the heating platen 1 and the remaining steam flow down the outlet pipe 7, the condensed water flows from the steam trap 8 into the header tank 9, and the remaining steam flows from the pipe 10 to the heating plate 2. It flows into the low pressure steam supply pipe 4. In this way, by supplying the remaining steam of the hot platen 1 to the hot platen 2 through the pipe line 10, it is possible to reliably generate a steam flow in the hot platen 1 and improve the thermal efficiency.

  Part of the steam supplied to the hot platen 2 becomes condensate and flows from the steam trap 12 to the header tank 9, and the remaining steam flows from the bypass valve 13 to the header tank 9. The steam in the header tank 9 is sucked into the suction chamber 16 of the steam ejector 5 through the pipe line 15, so that a steam flow can be reliably generated in the hot platen and the thermal efficiency can be improved.

  INDUSTRIAL APPLICABILITY The present invention can be used for a steam heating device as a thin hot plate of a corrugating machine used when manufacturing corrugated cardboard or the like.

DESCRIPTION OF SYMBOLS 1 Hot plate 2 Hot plate 3 High pressure steam supply pipe 4 Low pressure steam supply pipe 5 Steam ejector 7 Outlet pipe 8 Steam trap 9 Header tank 10 Pipe line 16 Suction chamber 17 Liquid pressure feeding member

Claims (1)

A steam heating apparatus using a first heat exchanger to which high-pressure steam is supplied and a second heat exchanger to which low-pressure steam is supplied ,
While directly connecting one of the outlet pipes on the outlet side of the first heat exchanger to the inlet side of the second heat exchanger, the other is connected to the header tank,
Connecting the outlet side of the steam ejector driven by the low-pressure steam to the inlet side of the second heat exchanger;
Steam heating apparatus, wherein a suction chamber of the steam ejector, in communication with the outlet side of the second heat exchanger via the header tank.

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