A method for quickly determining a position of a signal mouthpiece of spraying equipment, the spraying equipment mainly comprising a bolt (1), a water intake signal mouthpiece (4), an outlet cover plate (5), a sprayer body (6), a water storage vessel (10), a scale line (11), a conduit (12) and a water inlet connecting mouthpiece (13), the method for determining the position of the signal mouthpiece comprising the following steps:
- (a) the outlet cover plate (5) is fixedly connected threadably to the sprayer body (6) by means of threaded holes (14), the water intake signal mouthpiece (4) and the sprayer body (6) are clamped with the bolt (1) to determine the position of the water intake signal mouthpiece (4), and a coupling position of the water intake signal mouthpiece (4) is fixed by a locking nut a (2), the water intake signal mouthpiece (4) is disposed outside the outlet cover plate (5) in a vertical position, and a radial position of the water intake signal mouthpiece (4) relative to the outlet cover plate (5) can be adjusted through the bolt (1);
- (b) a rated operating pressure H of the spraying equipment is set, and firstly, the water intake signal mouthpiece (4) is enabled to receive a signal water, the locking nut a (2) is loosened, the bolt (1) is loosened, and the water intake signal mouthpiece (4) is moved until the water intake signal mouthpiece (4) is at a critical point where it is completely separated from the outlet cover plate (5), namely, a critical position where the water intake signal mouthpiece (4) cannot intake the signal water when a sprayer is at the operating pressure H, the bolt (1) is tightened, and a reference position of the outside of the water intake signal mouthpiece (4) is marked, that is, a reference line corresponding to the outside of the water intake signal mouthpiece (4) is drawn on an upper end of the outlet cover plate (5), the reference position corresponding to the reference line representing a set position where the water intake signal mouthpiece (4) is at 0;
- (c) the locking nut a (2) is loosened, the bolt (1) is loosened, the water intake signal mouthpiece (4) is adjusted to receive the signal water, and the set position where the water intake signal mouthpiece (4) corresponds to the outlet cover plate (5) is obtained, such that a water intake area S1 of the water intake signal mouthpiece (4) is a value, and the set position of the water intake signal mouthpiece (4) is fixed by tightening the bolt (1) and the locking nut a (2), such that the water intake area S1 remains unchanged during a sprayer operation;
- (d) the rated operating pressure H of the spraying equipment is set, the spraying equipment is kept in a stable operating state, and when the spraying equipment cannot be kept in the stable operating state, the step (c) above is repeated;
- (e) the conduit (12) is disconnected with a water intake port (9), the spraying equipment is kept in a direct ejection state to draw the signal water, a time tl it takes for the signal water to begin to enter the water storage vessel (10) until it is full is recorded, and a flow of the signal water of the sprayer per unit time Q1=W/t1 is calculated when the water intake area of the spraying equipment is S1;
- and a flow coefficient μ of the signal water of the spraying equipment is calculated according to the following formula:
- Q
- 1
- =
- μ
-
- S
- 1
-
- 2
-
- g
-
- H
- wherein,
- S1 is the water intake area of the water intake signal mouthpiece,
- H is the operating pressure of the sprayer,
- μ is the flow coefficient of the signal water of the spraying equipment, μ=Q1/S1√{square root over (2gH)};
- (f) on the basis of obtaining the value of the flow coefficient μ of the signal water of the spraying equipment in the step (e), based on a operating principle of the spraying equipment, and according to a formula:
- T
- =
- W
- +
- π
-
- r
- 2
-
- l
- Q
- 2
- =
- W
- +
- π
-
- r
- 2
-
- l
- μ
-
- S
- 2
-
- 2
-
- g
-
- H
- ,
- a water intake area of the signal mouthpiece of the spraying equipment S2 is calculated as
- S
- 2
- =
- W
- +
- π
-
- r
- 2
-
- l
- T
-
- μ
-
- 2
-
- g
-
- H
- and then the position of the signal mouthpiece of the spraying equipment is optimized according to an assumed expected direct ejection time T of the spraying equipment;
- (g) based on a length dimension of the water intake port of the water intake signal mouthpiece (4), starting from the reference line on the upper end of the outlet cover plate (5), m scale lines are drawn equidistantly on the outlet cover plate (5), such that the water intake area of the water intake signal mouthpiece (4) is divided into m equal parts;
- and a formula for calculating the water intake area of the signal mouthpiece of the spraying equipment is:
- S
- 2
- =
- x
- -
- 1
- m
-
- S
- wherein,
- S is a total area of the water intake signal mouthpiece, and
- x is a number of the position of the scale line of the outlet cover plate which the reference line of the signal mouthpiece corresponds to;
- and
- (h) the number of the position of the scale line of the outlet cover plate which the reference line of the signal mouthpiece corresponds to is determined:
- x
- =
- m
-
- S
- 2
- S
- +
- 1
- =
- m
-
- (
- W
- +
- π
-
- r
- 2
-
- l
- )
- S
-
- T
-
- μ
-
- 2
-
- g
-
- H
- +
- 1
- the locking nut a (2) is tightened to fix the set position of the water intake signal mouthpiece (4), and the expected direct ejection time T in the step (e) can be obtained, as such, the position of the signal mouthpiece of the spraying equipment can be quickly and conveniently determined.