CN1595322A - Water level control method of water tank - Google Patents

Abstract

The invention relates to an elevated tank water level control method applied to the feed water system of the hot-rolled strip steel coiling temperature control system. The method controls the feedwater flow of the feedwater tube to make the feedwater flow equal to or greater than the outflow according to the measured outflow of the outflow tube. The configuration requirement of the mechanical equipment and the control device of this control method is the same as that of the conventional method. The water level gauge only has the function of displaying the water level. With the same equipment, the water level can be controlled within 0.30~1.52m through the conventional control method, whereas it can be controlled within 1.20~1.51m through the directly flow controlling and the indirectly water level controlling method to feed water immediately. In addition, the invention is of high responding speed, perfect controlling effect, and the water level of the water tank fluctuates slightly.

Description

The cistern water level control method

Technical field

The present invention relates to a kind of control method of cistern water level, especially the method for controlling water level of the elevated tank of water system in the coiling temperature control system of hot-strip.

Background technology

The coiling temperature control system is one of automatic control system of domestic and international hot-strip factory most critical, and at present, modern hot-strip factory generally adopts the water system of elevated tank as the coiling temperature control system.The purpose that adopts high-level tank water is weighing apparatus constant flow and pressure, and dependable flow and the fixed means of pressure weighing apparatus are that the basic weighing apparatus of keeping the water level in the elevated tank is decided.Operated by rotary motion has a plurality of feed pipes and a plurality of rising pipe on the elevated tank, in order to reach the purpose of quick moisturizing, and owing to be difficult to realize the absolute equilibrium of moisturizing and water outlet, generally be to make the moisturizing ability be slightly larger than capacity of outlet water, the water that moment has more is crossed the barrier overflow and is gone out.Keeping the fixed conventional way of water level weighing apparatus is that a water level gauge is installed in water tank, a given datum level, control closing of moisturizing valve by computer control device according to the actual measured results of water level gauge, be that water level whenever is lower than certain scale and opens a water compensating valve, whenever be higher than certain scale and close a water compensating valve, this traditional water level control method is according to actual water level, determines the moisturizing activity, directly control water level.Conventional method for controlling water level, generally be to be benchmark with 1.45m, every decline/water compensating valve of rising 0.05m opening/closing is because in the moisturizing process, the water surface is uncalm, the water level instability, have only 0.1 second and gather a water level, as current actual water level, such result is that computing time is long with the mean value of 10 water levels in 1 second, the opening/closing of water compensating valve all seriously lags behind, and causes water-level fluctuation big.In a word, its weak point of above-mentioned traditional water level control method is the control algolithm complexity, acts frequently, response lag, control weak effect and water-level fluctuation are big, and is too strong to the quality and the state dependence of water level gauge.

Summary of the invention

Thereby in order to overcome existing cistern water level control method control weak effect, the untimely big deficiency of water-level fluctuation that causes of moisturizing, technical matters to be solved by this invention provides that a kind of response speed is fast, moisturizing cistern water level control method timely.

The technical solution adopted for the present invention to solve the technical problems is: this cistern water level control method is to control the refill flow of filling pipe according to the water flow of detected rising pipe, makes refill flow 〉=water flow.By this direct Control Flow, the indirect mode of control water level, thereby reach the effect of timely moisturizing, and response speed is fast, thereby the cistern water level fluctuation is little.

The invention has the beneficial effects as follows, this control method is identical to the configuration requirement and the conventional method of plant equipment, control device etc., but water level gauge is only got the effect that shows water level, the moisturizing action does not rely on the result of its detection, thereby, low than classic method on the contrary to the requirement of eigenwerts such as the precision of water level gauge, sensitivity, stability.So when using the water level gauge with quality, novel control method is more stable than traditional control method.Same a set of equipment, originally adopt traditional control method, water level is controlled between 0.30～1.52m, after adopting novel control method, water level is controlled between 1.20～1.51m, thereby adopt simple equipment, easy method, realized the accurate control of elevated tank water level, and response speed is fast, control is effective.

Description of drawings

Fig. 1 is a cisten mechanism synoptic diagram of the present invention.

Fig. 2 is a control device block scheme of the present invention.

Embodiment

The present invention is further described below in conjunction with drawings and Examples.

As shown in Figure 1 and Figure 2, cistern water level control method of the present invention is according to the flow equilibrium principle, directly determines refill flow by water flow, and sequential is opened/closed to the sequential of opening/close of control water compensating valve 7 immediately following outlet valve 6.Control the water level of water tank 3 indirectly by direct Control Flow.This cistern water level control method is controlled the refill flow of filling pipe 2, and is made refill flow 〉=water flow, thereby accomplish timely moisturizing, the little accurate control of the fluctuation of response, thereby guaranteed water level fast according to the water flow of detected rising pipe 1 time.

Above-mentioned control method can adopt various ways to realize, for example controls the refill flow of filling pipe 2 by the actual water flow of direct detected rising pipe 1, follows the tracks of aquifer yield dynamically and controls the next timely moisturizing of its inflow.

Above-mentioned control method also can adopt more simple and practical mode, promptly at first join a quantitative relation between the capacity of outlet water of the moisturizing ability by accurate each filling pipe of demarcation and each rising pipe, the moisturizing ability that is to say a capacity of outlet water of measuring how many root rising pipes 1 and a filling pipe 2 is suitable, control the quantity of the water intaking valve 7 of the filling pipe of opening simultaneously 2 then according to the quantity of the outlet valve 6 of the rising pipe 1 opened, the opening/close and the opening/close synchronously of water intaking valve 7 of outlet valve 6, thus reach the purpose of quick response, moisturizing in time.

Embodiment: as shown in Figure 1 and Figure 2, cistern water level control method of the present invention, the configurations of the planform of its elevated tank, control device 8 etc. are with traditional identical.5 of water level gauges are got the effect that shows water level, and the moisturizing action does not rely on the result of its detection, thereby, low than classic method on the contrary to the requirement of eigenwerts such as the precision of water level gauge 5, sensitivity, stability.Water tank 3 is divided into two parts by barrier 4, and the left side is a water storage box, is furnished with 10 filling pipes of bringing water valve 7 into 2 and 90 rising pipes of taking water valve 6 out of 1 that little bore is identical that big bore is identical, and water intaking valve 7 and outlet valve 6 are solenoid electric valve.Water tank 3 overall heights are 1.8m, and barrier 4 highly is 1.5m, owing to be difficult to realize the absolute equilibrium of moisturizing and water outlet, therefore, generally make the moisturizing ability be slightly larger than capacity of outlet water, moment more than water, cross barrier 4 and overflow.In order to leave certain surplus, so that the flow of every big filling pipe 2 must be greater than the flow of 9 little rising pipes 1.The flow that this control method will be demarcated the flow of every filling pipe 2 and how many root rising pipes 1 at first exactly is suitable, method is when not producing, open simultaneously 1 on the filling pipe 2 water compensating valve 7 and the outlet valve 6 on 9 rising pipes 1, this moment since the moisturizing ability greater than capacity of outlet water, the water level that water level gauge 5 detects can slowly raise naturally, in the elevation process of water level, append singly and open outlet valve 1, the water level ascending velocity is more and more slower naturally, when water level begins to descend, indicate discharge greater than refill flow, close outlet valve 6 this moment singly, basicly stable until water level.In a word, append when water level rises and open outlet valve 6, turn off indivedual outlet valves 6 during decline of water table, basicly stable until water level so repeatedly, the unlatching quantity of the outlet valve 6 of this moment is equilibrium number N.In process of production, when opening the outlet valve 6 of X rising pipe 1, the quantity of the water intaking valve 7 that need open is Y, then should satisfy following relationship between X, Y, the N:

X＝0 Y＝0

0＜X≤N Y＝1

N＜X≤2N Y＝2

2N＜X≤3N Y＝3

3N＜X≤4N Y＝4

4N＜X≤5N Y＝5

Control device is by the quantity of above-mentioned relation basis water intaking valve 2 on the filling pipe that the definite immediately needs of the quantity of the outlet valve 6 on the rising pipe 1 of front opening are opened.Because moisturizing is at the right time, water level can return to about 1.5m soon, overflows by part thereafter, keep the stable of water level and do not descend, but moment the flow that overflows be the flow of N-1 rising pipe 1 to the maximum.Therefore, this control method not only equipment is simple, easy to implement the method, and controls effective.

Claims (3)

1, cistern water level control method is characterized in that: according to the water flow while of detected rising pipe (1), control the refill flow of filling pipe (2), make refill flow 〉=water flow.

2, cistern water level control method as claimed in claim 1, it is characterized in that: at first join a quantitative relation between the capacity of outlet water of the moisturizing ability by accurate each filling pipe of demarcation and each rising pipe, control the water intaking valve quantity of the filling pipe of opening simultaneously (2) according to the quantity of the outlet valve of the rising pipe of opening (1), the opening/close and the opening/close synchronously of water intaking valve of outlet valve.

3, cistern water level control method as claimed in claim 2, it is characterized in that: adopt identical rising pipe (1) filling pipe (2) identical of bore with bore, the bore of filling pipe (2) is greater than the bore of rising pipe (1), if the flow of the flow of a filling pipe and N root rising pipe is suitable, when opening the outlet valve (6) of X rising pipe (1), the quantity of the water intaking valve (7) of the filling pipe that need open (2) is Y, then should satisfy following relationship between X, Y, the N:

X＝0 Y＝0

0＜X≤N Y＝1

N＜X≤2N Y＝2

2N＜X≤3N Y＝3

3N＜X≤4N Y＝4

4N＜X≤5N Y＝5

......。

Images