Current knowledge allows us to drill the wells, using rotary drilling with drillcollars in the vertical part. The wells will be completed with screens that cannot be rotated during installation. Because a non-rotating mode leads to higher friction, it is questionable if we are able to land the entire horizontal screen due to lack of weight at this shallow depth.

Excessive surface weight may lead to buckling of the completion string. Simulations of the completion operations suggest that there is a high risk of stopping before reaching the target depth.

A study was undertaken on a shallow well with long horizontal section including side turns in this section to see how much friction is increasing due to these bends in the wellbore. This study is helpful for designing directional/horizontal wellbores in order to find the best well path profile that minimizes well friction as well as is a planned profile in acceptable from friction prospective. For this reason the friction profile during hoisting/lowering first the real 3-D well with side bens inside and then with keeping azimuth constant in the same well was performed and resulting friction profiles were comparing.

The study is based on a new 3-dimensional analytical friction model that was developed in 2009. It is simple and uses the dogleg (which includes both inclination and azimuth) and is therefore fully three-dimensional. The analytical model is applied with some modifications in order to capture the effect of weight in the horizontal section especially when BHA is dragging up/down into or out of the wellbore.

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