University of Zagreb. Faculty of Mining, Geology and Petroleum Engineering. Department of Petroleum Engineering.
Abstract
Svi postupci kontrole tlaka oslanjaju se na rano prepoznavanje dotoka i zatvaranje bušotine kako bi se spriječio daljni dotok. Nakon zatvaranja bušotine, pristupa se ugušivanju bušotine različitim metodama, najčešće bušaćom ili inženjerskom metodom kontrole tlaka. Poznate su prednosti i nedostaci obje metode, sa bušaćom metodom se može započeti odmah nakon očitanja tlakova, dok se inženjerskom metodom razvijaju manji tlakovi na ušću bušotine i u području pete kolone. Razvoj tlakova tijekom ugušivanja može se pratiti na temelju karakerističnih očitanja: početnog cirkulacijskog tlaka, konačnog cirkulacijskog tlaka i tlaka na ušću bušotine. Izrađenim modelom izračunati su karakteristični tlakovi u ovisnosti o hodovima pumpe nakon zatvaranja bušotine. Izrađeni model uz nekoliko pretpostavki potvrđuje razvoj manjih tlakova tijekom provedbe inženjerske metode. U stvarnosti, to ne mora nužno biti slučaj.Abstract: Well killing methods rely on early kick detection and shutting in the well to prevent any further influx into wellbore. When the well is shut in, appropriate well kill method is selected, most commonly, driller's method or wait & weight method. Advantages and disadvantages of both methods are known, well kill procedure using driller's method can start immediately, while using wait & weight method lower pressure in the annulus are developed. Pressure profile can be tracked with characteristic pressures during well kill procedure: initial circulation pressure, final circulation pressure and casing pressure. Characteristic pressures are calculated using pressure model for well kill procedures, with few assumptions. Pressure model confirms lower casing pressures during wait & weight method, while in real situation, that does not have to be case
