Automation Systems Design and Laboratory Prototyping Aimed at Mature Petroleum Drilling Rig Retrofitting

This paper presents a control system design methodology for the drill-string rotary drive and draw-works hoist system aimed at mature drilling rig retrofitting. The rotary drive is equipped with an active damping speed control system featuring a proportional-integral speed controller readily available within modern controlled electrical drives, extended with drill-string back-spinning prevention scheme for the case of stuck tool. The draw-works hoist system features a tool normal force (Weight-on-Bit) controller with tool longitudinal speed (Rate-of-Penetration) limiting functionality. The design of proposed control systems has been based on suitable control-oriented process models and damping optimum criterion which guarantees a desired level of closed-loop system damping. The proposed drilling control systems have been verified on a downscaled laboratory experimental setup, which represents a necessary pre-requirement before these systems are tested in the field

Retrofitting design of an automated drilling system using the legacy mechanical brake and test results from Crosco\u27s N-402 drilling rig

Značajan dio bušaćih postrojenja koja su danas u upotrebi i dalje je opremljen mehaničkim sustavima upravljanja silom nasjeda bušaćeg alata (WoB) i njegovom brzinom prodiranja (RoP) zasnovanim na polužnom mehanizmu kočnice vitla dizalice kojim upravlja ljudski operater. Kako bi se zadovoljili sve stroži zahtjevi u pogledu izvedbe WoB/RoP sustava upravljanja, uključujući potpuno automatski rad (automatsko bušenje), takve „zrele“ pogonske sustave za upravljanje procesom bušenja potrebno je nadograditi odgovarajućim servo mehanizmom polužnog aktuatora kočnice, zajedno s odgovarajućim WoB/RoP regulacijskom strategijom. Stoga se u ovom radu predstavlja razvoj sustava za kontrolu WoB/RoP zasnovan na elektromotornom servoaktuatoru kočnice pogona vitla dizalice bušaćeg niza. Sveukupni upravljački sustav organiziran je u takozvanu kaskadnu strukturu regulacije, sa nadređenom regulacijskom petljom sa proporcionalno-integralnim (PI) regulatorom sile nasjeda, koji zadaje komandu brzine prodiranja PI regulatoru na nižoj razini koji regulira brzinu prodiranja, a koji pak zadaje referencu položaja servopogonu polužnog mehanizma aktuatora kočnice. Predloženi sustav regulacije WoB/RoP implementiran je na industrijskom upravljačkom hardveru, koji je potom instaliran i detaljno ispitan na kopnenoj bušaćoj garnituri N-402 tvrtke CROSCO, naftni servisi, d.o.o.A notable portion of contemporary deep drilling rigs are still equipped with manually-operated lever-based draw-works (hoist) drum mechanical brake actuators, which are used for weight-on-bit (WoB) and rate-of-penetration (RoP) control. In order to meet increasingly stringent requirements on the WoB/RoP control performance, including completely automatic vertical drilling operation (auto-drilling), such mature drilling systems need to be retrofitted with a suitable brake actuator servo mechanism, along with appropriate WoB/RoP control strategy. To this end, this paper presents the development of a weight-on-bit and penetration rate control system based on electrical servomotor-based draw-works brake actuator. The control system has been arranged in the so-called cascade control system structure, wherein the superimposed control loop based on the proportional-integral (PI) WoB controller is commanding the inner RoP PI controller, which in turn provides a position reference to the brake lever mechanism servo-actuator. The proposed WoB/RoP control system has been implemented on industrial control hardware that has been subsequently installed and thoroughly tested on the CROSCO oilfield services Ltd. N-402 land drilling rig