Hydraulic Orifices
Their Function:
Orifices are used in hydraulic systems to restrict flow
Sizing:
To calculate the orifice diameter required to pass a desired flow at a specific pressure
D = 0.23 x √(Q ÷ √Δp)
Where
Q = Flow in US Gallons per Minute
D = Orifice Diameter in Inches
Δp = Differential Pressure across Orifice
Assuming: Specific Gravity = 1 and Orifice Coefficient = 0.63
To calculate the flow through an orifice of a known diameter at a specified pressure
Q = (D ÷ 0.23)² x √Δp
Where
Q = Flow in US Gallons per Minute
D = Orifice Diameter in Inches
Δp = Differential Pressure across Orifice
Assuming: Specific Gravity = 1 and Orifice Coefficient = 0.63
To calculate the pressure drop (differential pressure) across an orifice of a known diameter at a specific flow
Δp = 〈Q ÷ (D ÷ 0.23)²〉²
Where
Δp = Differential Pressure across Orifice
Q = Flow in US Gallons per Minute
D = Orifice Diameter in Inches
Assuming: Specific Gravity = 1 and Orifice Coefficient = 0.63