Case History of First Liner Drilling Application in Romania Ali Qureshi Well Delivery Team Leader-Team-5 OMV Petrom S.A. Bucharest, 28 th April 2016
Agenda Introduction Background (well design, prognosis etc.) Sequence of Events System Specs Conclusions and Recommendations 2
Romania 3
Well Design Romaian Dacian Pontian Meotian KCl mud 1.15 1.2 SG 13 3/8 Surface CSG Well Design Casing objectives: 1) 13 3/8 Surface Casing @ Sarmatian formation top: 1- Support unconsolidated top formation 2- Isolate active shale in Meotian formation 3- Implement CwD Technology Sarmatian NADF mud 1.25 1.35 SG 2) 9 5/8 Production Casing @ Salt formation top: Case off long Sarmatian formation open hole section. 3) 7 Production Liner @ T2 formation top: Case off and isolate Salt formation section. Jurassic / Salt Triassic Paleozoic 9 5/8 Production CSG NADF mud 1.8 1.85 SG 7 Production Liner NADF mud 1.2 1.25 SG 6 OH section 4) 6 OH Section Drill 6 hole through T2, T1 and Paleozoic formation with mud weight 1.20-1.25 SG NADF to avoid losses in Paleozoic formations. 4
Well Prognosis 5
Planned Well Path 6
What happened? (1 of 2) Drilled through Sarmatian and Badenian formations; encountered aggressive salt layer @ 4238mMD. Bit got stuck in salt @ 4239mMD. Jarring and pumping fresh water pills didn t work. MW 1.35sg (NADF). Cut and retrieve string; 20m fish left in hole. TOF @ 4219m. Pump and set cement plug above fish. Dressed down top of cement to 4150mMD, then ran and cemented 9 5/8 casing above fish. Drilled out shoe-track, kicked-off from 4163m, 56m above TOF, to perform side-track #1. Drilled through salt with 1.73sg to section TD @ 4326mMD; MW limited by losses in exposed sand layers below 9 5/8 casing shoe. POOH. Ran 7 liner, equipped with reamer shoe; stood up at 4245mMD (HUD). 7
What happened? (2 of 2) POOH liner to perform wiper trip. RIH dumb iron BHA, accidentally side-tracked from 4245mMD in open hole (side-track #2) while trying to ream obstruction; POOH, switch to directional BHA and drilled ahead through salt to casing point at 4326mMD. RIH 7 liner; could not pass salt layer. POOH and set another cement plug @ 4022mMD. Drill out cement to 4157mMD. RIH directional BHA, side-track hole again from 4157mMD (side-track #3). Drill to top of salt, POOH BHA. RIH 7 liner with casing bit and rotating liner hanger system. Drilled through salt successfully from 4238mMD 4255mMD (17m); average ROP 5 m/hr. No further progress possible. Cemented liner in place. 8
Mud Log from the problematic section 9
Liner Drilling Parameters Chart 10
Actual Well Trajectory in Reservoir Section 11
Liner Drilling Bit 12
Liner Systems Central Europe End of Job Report System Specs Description Well Schematic Depths Weatherford Liner Hanger System: Hydraulics Set Rotating Liner Hanger System Premium Liner System with Dual Plug System and Top Set Packer Type R Running tool, MX Ball Seat Top of Liner Packer Element Measured 3923m Measured N/A True Vertical 3922m True Vertical N/A 7 Liner: 32PPF, TN110HS, TN Blue M/U Torque: 13,000 ft-lbs Hanger Slips Measured 3930m True Vertical 3929m Previous Casing Exit Measured 4251m True Vertical 4247m Top of Shoe Tract Measured 4226m True Vertical 4224m 13 Liner Shoe Section TD Measured True Vertical 4254m 4252m Measured True Vertical 4254.8m 4252.7m
Conclusions and Recommendations Drilling with liner (DwL) helped to cross the problematic salt layer and facilitated drilling ahead to the targeted reservoir. It was first such application in Romania; promising technology to case off problematic formations. Stronger bit could have drilled further; bit selection can be improved. 7 liner and Liner hanger system worked fine; no issues encountered. Some pressure fluctuations were observed while drilling, could be from bit nozzles washing out but cannot be confirmed. 14
Thank you! Any Questions? 15