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The flow characteristic (hydraulic cylinder)

The flow characteristic (hydraulic cylinder) r a b β α r a b β T L S S a 2 a 1 γ δ α
The flow characteristic (hydraulic cylinder)

Values for calculation

$α$ $\mathrm{°}$
$β$ $\mathrm{°}$
$r$ $\mathrm{mm}$
$a$ $\mathrm{mm}$
$b$ $\mathrm{mm}$
$L_d$ $\mathrm{\%}$
$T_c$ $\mathrm{s}$
$T_d$ $\mathrm{s}$
$K_{Q-valve}[1]$
$K_{Q-valve}[2]$
$K_{Q-valve}[3]$
$K_{Q-valve}[4]$
$K_{Q-valve}[5]$
$K_{Q-valve}[6]$
$K_{Q-valve}[7]$
$K_{Q-valve}[8]$
$K_{Q-valve}[9]$
$K_{Q-valve}[10]$

Calculation

Stroke

$$S_{max}=\sqrt{\left(b-r\cdot\sin{\left(α+β\right)}\right)^2+\left(a-r\cdot\cos{\left(α+β\right)}\right)^2}-\sqrt{\left(b-r\cdot\sin{\left(α\right)}\right)^2+\left(a-r\cdot\cos{\left(α\right)}\right)^2}$$

Distance between the axis of rotation of the valve and the axis of the hydraulic cylinder

$$L=\sqrt{a^2+b^2}$$

Requirements

$$α\geq\tan^{-1}{\cfrac{b}{a}}\cdot\cfrac{180}{π}$$$$β\le\tan^{-1}{\cfrac{b}{a}}\cdot\cfrac{180}{π}+180-α$$$$0.8\cdot T_c\geq T_d$$
Stroke from open position
The distance between the axis of the hydraulic cylinder and the axis of the eye of the hydraulic cylinder
Height $ T $
The angle between the axis of the hydraulic cylinder and the imaginary line between the axis of the closure and the pivot axis of the hydraulic cylinder
$s$ $S_S$ $T$ $γ$
$\mathrm{\%}$ $\mathrm{mm}$ $\mathrm{mm}$ $\mathrm{°}$
No data

$S_S \mathrm{[mm]}$
No data
$s\mathrm{[\%]}$
The distance between the axis of the hydraulic cylinder and the axis of the eye of the hydraulic cylinder

$$S_S=S_{max}-\cfrac{S_{max}}{100}\cdot s+\sqrt{\left(b-r\cdot\sin{\left(α\right)}\right)^2+\left(a-r\cdot\cos{\left(α\right)}\right)^2}$$

$T \mathrm{[mm]}$
No data
$s\mathrm{[\%]}$
Height $ T $

$$T=\sqrt{S_S^2-\left(\cfrac{L^2-r^2+S_S^2}{2\cdot L}\right)^2}$$

$γ \mathrm{[°]}$
No data
$s\mathrm{[\%]}$
The angle between the axis of the hydraulic cylinder and the imaginary line between the axis of the closure and the pivot axis of the hydraulic cylinder

$$γ=\sin^{-1}{\cfrac{T}{S_S}}\cdot\cfrac{180}{π}$$
Stroke from open position
Length $ a_2 $
Length $ a_1 $
The angle between the lever axis and the imaginary line between the valve axis and the pivot axis of the hydraulic cylinder
Angle rotation of the rocking motion
$s$ $a_2$ $a_1$ $δ$ $β_S$
$\mathrm{\%}$ $\mathrm{mm}$ $\mathrm{mm}$ $\mathrm{°}$ $\mathrm{°}$
No data

$a_2 \mathrm{[mm]}$
No data
$s\mathrm{[\%]}$
Length $ a_2 $

$$a_2=S_S\cdot\cos{γ}$$

$a_1 \mathrm{[mm]}$
No data
$s\mathrm{[\%]}$
Length $ a_1 $

$$a_1=L-a_2$$

$δ \mathrm{[°]}$
No data
$s\mathrm{[\%]}$
The angle between the lever axis and the imaginary line between the valve axis and the pivot axis of the hydraulic cylinder

$\text{if }\ a_1\le0$
$$δ=90+\cos^{-1}{\cfrac{T}{r}}\cdot\cfrac{180}{π}$$
$\text{else}$
$$δ=90-\cos^{-1}{\cfrac{T}{r}}\cdot\cfrac{180}{π}$$

$β_S \mathrm{[°]}$
No data
$s\mathrm{[\%]}$
Angle rotation of the rocking motion

$$β_S=δ_{[0]}-δ$$
Stroke from open position
Flow coefficient $ K_{Q-valve} $
Flow coefficient $ K_{Q-hydraulic-cylinder} $
$s$ $K_{Q-valve}$ $K_{Q-hydraulic-cylinder}$
$\mathrm{\%}$ $\mathrm{ }$ $\mathrm{ }$
No data

$K_{Q-valve} \mathrm{[-]}$
No data
$s\mathrm{[\%]}$
Flow coefficient $ K_{Q-valve} $

$K_{Q-hydraulic-cylinder} \mathrm{[-]}$
No data
$s\mathrm{[\%]}$
Flow coefficient $ K_{Q-hydraulic-cylinder} $

$\text{if }\ s=0$
$$K_{Q-hydraulic-cylinder}=K_{Q-valve}$$
$\text{else if }\ s=100$
$$K_{Q-hydraulic-cylinder}=K_{Q-valve}$$
$\text{else}$
$$K_{Q-hydraulic-cylinder}=K_{Q-valve}-\cfrac{K_{Q-valve}-K_{Q-valve}[i+1]}{β/10}\cdot\left(β_S-\cfrac{β}{100}\cdot s\right)$$
Time value
Percentage of hydraulic cylinder stroke at a given time
Flow coefficient
$T_s$ $S_T$ $K_Q$
$\mathrm{s}$ $\mathrm{\%}$ $\mathrm{ }$
No data

$S_T \mathrm{[\%]}$
No data
$T_s\mathrm{[s]}$
Percentage of hydraulic cylinder stroke at a given time

$\text{if }\ T_s<\left(T_c-T_d\right)$
$$S_T=\cfrac{100-L_d}{T_c-T_d}\cdot T_s$$
$\text{else}$
$$S_T=100-L_d+\cfrac{L_d}{T_d}\cdot\left(T_s-T_c+T_d\right)$$

$K_Q \mathrm{[-]}$
No data
$T_s\mathrm{[s]}$
Flow coefficient

$\text{if }\ s=0$
$$K_Q=K_{Q-hydraulic-cylinder}$$
$\text{else if }\ s=100$
$$K_Q=K_{Q-hydraulic-cylinder}$$
$\text{else}$
$$K_Q=K_{Q-hydraulic-cylinder}-\cfrac{K_{Q-hydraulic-cylinder}-K_{Q-hydraulic-cylinder}[i+1]}{10}\cdot\left(S_T-s\right)$$
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