JP3360239B2 - Control method of steam consuming device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a steam consuming device for supplying steam to a steam device through a valve for controlling the pressure and temperature of the steam. Specifically, in a chemical device such as a concentrating device, a distillation device or a reaction vessel, a medical device such as an autoclave or a sterilizing device, or a variety of heating devices, the pressure and temperature of steam are controlled to efficiently produce an object to be heated. Equipment
Control method .

[0002]

2. Description of the Related Art Conventionally, when heating various products using steam generated by a boiler, a combination of a so-called automatic control valve, a temperature sensor and a controller has been used. When not only temperature but also steam pressure must be controlled, a combination of pressure sensors has been used. The temperature of the heated object or the pressure of the supplied steam is sensed by a temperature sensor or a pressure sensor, and the pressure of the heated steam to the steam consuming device is adjusted by controlling the automatic control valve via the controller. And the amount is controlled to heat the object to be heated at a predetermined temperature.

[0003]

In the above-mentioned conventional device, a plurality of sensors for sensing temperature and pressure are used.
Therefore, there is a problem in that the device becomes expensive, and each sensor and controller must be connected, which complicates the operation.

Accordingly, a technical problem of the present invention is to provide a low-cost and easy-to-install steam consuming apparatus that does not require a plurality of sensors.
Control method .

[0005]

Means for Solving the Problems The technical means of the present invention taken to solve the above technical problem is that a control valve connected to a steam source and the control valve are provided on one surface of a pressure responsive member. A pressure reducing valve that receives the secondary fluid pressure, receives the elastic force of the elastic member on the other surface, and opens and closes a main valve through which steam flows by the displacement of the pressure responsive member. The elastic force of the elastic member is adjusted by the pressure reducing valve. A storage unit for storing the relationship between the elastic force of the elastic member and the set pressure and the set temperature, and setting input means for inputting the set pressure and the set temperature. A valve provided with a drive control unit that drives the elastic force adjusting means by a desired amount based on the relationship between the input value of the storage unit and the input value of the storage unit, and the control valve is connected to a device that consumes steam. A predetermined temperature, e.g. boiling of liquid Until reaching performs temperature control by inputting the set temperature from the set temperature inputting means, it is characterized in that controlling the pressure by entering the set pressure and a set pressure input means reaches the boiling point.

[0006]

The operation of the above technical means is as follows.
By supplying steam to the steam consuming device via the control valve, the object to be heated in the steam consuming device is steam-heated. In this case, by adjusting the elastic member of the control valve by the elastic force adjusting means, the elastic force applied to the pressure responsive member changes, and the secondary pressure is automatically adjusted to balance the elastic force. By the function of a so-called pressure reducing valve, the secondary steam pressure of the valve is controlled to a desired value.

[0007] Steam, more specifically saturated steam, has a one-to-one relationship between pressure and temperature, and when the steam pressure is determined, the steam temperature is automatically determined. Therefore, when the set temperature of the control valve is input by the setting input means, the elastic force is calculated to be the set temperature from the set temperature in the storage unit, that is, the relationship between the steam pressure and the elastic force of the elastic member in a one-to-one relationship. Then, the control valve is set by driving the elastic force adjusting means so as to generate the elastic force, and the object to be heated is heated by the steam consuming device while maintaining the secondary-side steam temperature at the set temperature.

The steam pressure can be maintained at a desired value by inputting a desired set pressure from the setting input means, and the steam temperature can be maintained at a desired value by inputting a desired set temperature.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment showing a specific example of the above technical means will be described (see FIGS. 1 and 2). In this embodiment, an example in which a distillation still is used as a steam consuming device will be described. In FIG. 1, a control valve 1 and a steam supply pipe 2 for supplying steam to the control valve 1
A steam pipe 3 for supplying steam to the distillation still 30;
Steam trap 31 and cooler 3 attached to pipe end
2 together constitute a steam consuming device.

As shown in FIG. 2, the control valve 1 shuts off supply of high-pressure steam on the primary side to a main valve 8 for shutting off passage of steam, a piston 9 cooperating with the main valve 8, and an upper chamber 10 of the piston 9. A pilot valve portion 11, a diaphragm 12 as a pressure responsive member for driving the pilot valve portion 11, a secondary pressure introducing passage 14 for introducing a secondary fluid pressure into a lower chamber 13 of the diaphragm 12, and an upper surface of the diaphragm 12. Spring 15 as an elastic member acting on the coil spring, and an adjusting screw 16 as elastic force adjusting means for adjusting the elastic force of the coil spring 15
And a motor 17 as a drive unit for driving the adjustment screw 16
And the speed reducer 18.

The drive control unit 5 has a built-in storage unit (not shown) for storing the relationship between the set pressure of the control valve 1 and the elastic force of the coil spring 15, and the relationship between the saturated steam pressure and the temperature. The set pressure input means 6 and the set temperature input means 7 are not shown, but may be any as long as they can input arbitrary values using a numeric keypad or the like.

In this embodiment, the coil spring 15 as an elastic member exerts an elastic force in the downward direction of the diaphragm 12. However, when the so-called vacuum steam under the atmospheric pressure is reduced, the elastic force is reduced. A coil spring acting in the opposite direction, that is, in the upward direction, can also be used.

The control valve 1 has a separator 20 for separating condensed water as condensed water contained in the high-pressure steam supplied from the steam supply pipe 2, and a condensate which floats and descends by the separated condensed water. A steam trap portion 23 including a float 22 for opening and closing the valve port 21 is integrally attached.

A distillation pot 30 shown in FIG. 1 has a steam pipe 3 passing through the inside thereof, and is connected to a cooler 32 via a pipe 33 at an upper portion. As a result, predetermined components evaporate and the cooler 32
To cool and condense.

Next, the operation will be described. When evaporating by raising the temperature of the distillate in the still 30, first, temperature control is performed so that the distillate has a predetermined temperature. That is, when the set temperature is input from the set temperature input means 7 in the drive control unit 5 of the control valve 1, the storage unit in the drive control unit 5 similarly calculates the steam pressure and the elastic force of the coil spring 15 with respect to the set temperature value, The motor 17 is rotationally driven to generate the elastic force to compress the coil spring 15. Therefore, the steam supplied from the steam supply pipe 2 is throttled by the main valve 8 and flows down to the steam pipe 3 on the secondary side as steam reduced in pressure to the set temperature, that is, the steam pressure. Heat.

When the distillate reaches a predetermined temperature, for example, the boiling point, the temperature of the distillate does not change. Therefore, pressure control is performed instead of temperature control. That is, the set pressure is input from the set pressure input means 6, and the elastic force of the coil spring 15 with respect to the set pressure in the storage unit is calculated in the drive control unit 5, and the coil spring 1
5 is adjusted, and steam at a desired pressure is supplied from the control valve 1 to the still 30.

When the pressure in the steam pipe 3 decreases below the set value, the diaphragm 12 is pushed down by the elastic force of the coil spring 15 and the pilot valve 11 is opened, so that the high-pressure steam on the primary side is released from the piston upper chamber 10. When the piston 9 is displaced downward, the main valve 8 opens to replenish steam to the steam pipe 3, and the secondary side of the control valve 1 is maintained at the set pressure value.

In the present embodiment, an example has been shown in which the steam pipe 3 passes through the inside of the still 30 to indirectly heat the distillate. However, a direct heating apparatus in which the heated steam is brought into direct contact with the object to be heated and heated. Can be similarly implemented. Further, one of the setting input means 6 and 7 is preferentially operated, so that one of the temperature and the pressure can be main-controlled and the other can be sub-controlled.

[0019]

According to the present invention, by inputting the set pressure and the set temperature from the setting input means without using the pressure sensor and the temperature sensor, only the steam pressure is utilized by utilizing the one-to-one relationship between the steam pressure and the temperature. Alternatively, the temperature can be controlled to supply the desired steam to the steam consuming device.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of a control method of a steam consuming device of the present invention.

FIG. 2 is a cross-sectional configuration diagram of a control valve used in the method for controlling the steam consuming apparatus of the present invention in FIG.

Claims (1)

(57) [Claims] A control valve connected to a steam source, the control valve receiving a secondary fluid pressure on one surface of a pressure responsive member and receiving an elastic force of an elastic member on another surface, thereby displacing the pressure responsive member. A pressure reducing valve that opens and closes a main valve through which steam flows down. The pressure reducing valve is provided with elastic force adjusting means for adjusting the elastic force of the elastic member, and stores the relationship between the elastic force of the elastic member and the set pressure and the set temperature. A setting control means for inputting a set pressure and a set temperature, and a drive control section for driving the elastic force adjusting means by a desired amount based on an input value from the setting input means and a relationship in the storage section. And the control valve connected to a device that consumes steam.
Te, until steam consuming device reaches a boiling point of a predetermined temperature, for example liquid performs temperature control by inputting the set temperature from the set temperature inputting means, the pressure control by inputting the set pressure and a set pressure input means reaches the boiling point A method for controlling a steam consuming device.