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