Proving Tanks (Tank Provers)

Proving Tanks are precision open volumetric calibrating measures. They enable on site calibration of liquid Flow Meters, Master Meters & vehicle tanks with high degree of accuracy & reliability.


  • Rugged and fully welded construction
  • Displacement tube for accurate volumetric adjustment
  • Internal baffle plate prevents vortex formation and related trapping of air
  • Provision to mount thermometers and level bottle for accurate liquid measurement
  • Fixed or mobile versions with or without unloading pump and motor


Proving Tanks are designed and manufactured in accordance with Indian Standard IS:2341 and Manual of Weights & Measures.

A Proving Tank consists of a cylindrical shell welded between two conical ends, which ensures smooth flow of liquid while draining the tank. Fitted to the bottom cone is a T-joint (where inlet and outlet isolation valves can be fitted) and a drain valve to assist in filling and draining of the tank. The top cone is fitted with a neck tube, having a conical top cover to prevent ingress of dirt in the tank.

A graduated glass tube is externally fitted to the neck tube, which indicates the liquid level in the neck tube. Graduations on the tube correspond to the volume per unit height of the neck tube.

The cylindrical shell has a manhole fitted with a bolted cover, which can be opened for internal inspection, painting, etc. A displacement tube arrangement is provided on the top cone to adjust the internal tank volume with the tank capacity mark on the graduated glass tube. For accurate adjustment of tank level, rest pad is fixed to the top cone for keeping level bottles. The body also has two thermowells capable of accepting mercury in steel type thermometers.

A baffle plate provided at the point of liquid entry in the bottom cone, prevents swirl or vortex formation and related trapping of air in the liquid. The entire tank is erected on a sturdy steel channel frame, which can be either grouted (for a fixed Proving Tank) or bolted to a movable trolley (in case of a mobile Proving Tank). In the latter case, the trolley comes with a tow bar and leveling screw jacks. The choice of a centrifugal pump with motor to fill or drain the liquid is optional, both for fixed or mobile tanks.


  • Calibration of field mounted liquid flow meters or master meters
  • Vehicle tank calibration
  • Calibration of bulk measures