An orifice is an opening made in the side or bottom of tank, having a closed perimeter, through which the fluid may be discharged. A mouthpiece is short tube fitted to a same size circular opening provided in a tank so that fluid may be discharged through it. Orifice and mouthpiece are used to measure the rate of flow of liquid. The apparatus is designed to measure the co-efficient of discharge of orifice & mouthpiece. 
The apparatus consists of a supply tank at the side of which a universal fixture for mounting orifice or mouthpiece is attached. A centrifugal pump supplies the water to supply tank. Head over the orifice/mouthpiece is controlled by a by pass valve
provided at pump discharge. A measuring tank is provided to measure the discharge. A gauge for measuring X and Y co-ordinates of jet from the orifice is provided, which is used to calculate CV of orifice.
Salient Features

• Supply Tank : 0.4 X 0.3 X O.5 m height 
• Orifice : 8mm and 10mm.
• Mouthpiece 
• LID = 4 
• LID = 1 
• Bordas mouthpiece.
• Convergent mouthpiece.
• X·Y gauge for orifice jet co-ord1nates. 
• Measuring tank of suitable capacity OR a calibrated water flow meter. 
• Sump tank of suitable capacity. 
• 0.5 HP pump with valve.