Ravva - Cairn’s first development success story has been the bedrock of innovation, and the foundation of our success story in the country and the region. Ravva, which in Sanskrit and Telegu means “diamond” showcases the journey of growth that Cairn has been able to achieve in its business. Incidentally, Ravva is the only field in India to get such a unique name indicating the belief of the nation in it.

1.
RAVVA
Celebrating 16 Years of Technical Excellence
Offshore Gas Lift Project

2. RAVVA – Celebrating 16 years of Technical Excellence
Pioneering Development
Offshore Gas Lift Project
The production rate obtained from a well is the combined effect of reservoir deliverability, well bore
pressure gradient, and the flow line multiphase flow pressure change. When the well starts producing
water, deliverability of the well gets affected by hydrostatic head of the fluid. To enhance the production
rate, artificial lift processes are implemented. Artificial lift is a procedure to either increase the gas-liquid
ratio to maintain the natural flow or to transfer energy downhole to pump the fluid and raise its pressure.
Types of artificial lifts widely used:
 Gas lift
 Plunger lift
 Rod pump
 Electrical submersible pump
 Progressive cavity pump
 Hydraulic pump
Gas lift process involves injecting gas
through the tubing-casing annulus.
Injected gas aerates the fluid to
reduce its density; the formation
pressure is then able to lift the oil
column and forces the fluid out of the
wellbore. Gas may be injected
continuously or intermittently,
depending on the producing
characteristics of the well and the
arrangement of the gas-lift
equipment.
The amount of gas to be injected to
maximise oil production varies based
on well conditions and geometries.
Too much or too little injected gas will
result in less than maximum production. Generally, the optimal amount of injected gas is determined by
well tests, where the rate of injection is varied and liquid production (oil and perhaps water) is measured.
The offshore gas lift project at Ravva has resulted in advantages like:
Low initial and operating costs
 Maximising the use of available natural energy from a reservoir
 Flexibility of production - can produce at high and low rates
 Excellent handling of sandy conditions
 Allows full bore tubing draft
 Effectively produce high Gas and Water Oil Ratio (GOR and WOR) wells
 Minimal moving parts
 Subsurface equipment can use wire line workover techniques
The various types of gas lift operations are:
 Unloading operation used in initial kickoff/ activation of the well to lift up all drilling/ balancing
fluids
 Continuously injecting gas into the tubing or casing, at a predetermined depth to reduce the back
pressure on the reservoir/to reduce the hydrostatic gradient in the well bore
 Injection of high pressure gas into the tubing at a predetermined depth & flow rate intermittently to
enhance the well deliverability (de-watering gas wells)