Publications

The use of tubingless completion operations in Tunu field has allowed Total E&P Indonésie to decrease the cost and time per well when compared with previous monobore type completions. Although this cost saving initiative is not new for the industry, in the particular case of Tunu field, a very important constraint had to be solved first.One of the biggest constraints of the tubingless completion operations performed in Tunu field is how to avoid any under- or over-displacement while cementing the 4-1/2 completion tubing as the production casing. As an additional constraint, this must be achieved while keeping the so called “shoe track at an industry minimum value in order to avoid either drilling deeper into high pressure zones or leaving reserves without perforating as both choices could have important HSE and cost impacts. Solving these problems could lead to substantial costs savings and accelerated production.To overcome these problems, TOTAL E&P Indonesie and the local company P.T. Saga Trade Murni codeveloped a simple and low cost device, called “calibration plug, that allows avoiding all the above mentioned constraints.Several qualification tests had been performed on the calibration plug design in order to meet industry standards. These tests included erosion test, pressure and temperature test, compression strength test and rupture disk tests. The whole process starting from the design until the manufacturing of the calibration plug was performed in Balikpapan, Indonesia and is a good example of the “working together philosophy that TOTAL E&P Indonesie is constantly promoting with its local contractors and community.Since the introduction of the calibration plug in January 2003, more than 80 tubingless wells have already been completed with an impressive record of 100% achievement, confirming that the calibration plug device is also field proven and reliable.This simple, innovative and very cheap device has allowed reducing the shoe track length to a very minimum (5 to 10 meters from an original length of 40m) while: Avoiding drilling additional meters with the risk of entering into high pressure zones Eliminating risks of leaving reserves that cannot be accessed ( behind the shoe track) Eliminating risks of potential remedial operations ( +/- 100KUSD per operation) Avoiding any volumetric discrepancy while displacing the cement slurry as the bump is mandatory to pressure test the tubing to its full working pressureThis paper will discuss and explain the design, factory acceptance test and working procedure in more detail.