The document discusses the feasibility of using radial drilling technology at Imperial Energy fields in Russia to enhance oil production. It provides details on radial drilling such as how it can drill 1-2 inch lateral bores up to 300 feet long from existing wells to access more of the reservoir. The technology has proven effective in mature fields by improving production rates, reducing decline rates, and accessing bypassed oil. However, it also notes limitations including lack of control over drilling direction and inability to intervene if an undesirable zone is entered. The document recommends comparing results from a planned radial drilling project in India to the geological data from Imperial's wells before deciding to use it in Russia.
The document discusses the feasibility of using radial drilling technology at Imperial Energy fields in Russia to enhance oil production. It provides details on radial drilling such as how it can drill 1-2 inch lateral bores up to 300 feet long from existing wells to access more of the reservoir. The technology has proven effective in mature fields by improving production rates, reducing decline rates, and accessing bypassed oil. However, it also notes limitations including lack of control over drilling direction and inability to intervene if an undesirable zone is entered. The document recommends comparing results from a planned radial drilling project in India to the geological data from Imperial's wells before deciding to use it in Russia.
The document discusses the feasibility of using radial drilling technology at Imperial Energy fields in Russia to enhance oil production. It provides details on radial drilling such as how it can drill 1-2 inch lateral bores up to 300 feet long from existing wells to access more of the reservoir. The technology has proven effective in mature fields by improving production rates, reducing decline rates, and accessing bypassed oil. However, it also notes limitations including lack of control over drilling direction and inability to intervene if an undesirable zone is entered. The document recommends comparing results from a planned radial drilling project in India to the geological data from Imperial's wells before deciding to use it in Russia.
The document discusses the feasibility of using radial drilling technology at Imperial Energy fields in Russia to enhance oil production. It provides details on radial drilling such as how it can drill 1-2 inch lateral bores up to 300 feet long from existing wells to access more of the reservoir. The technology has proven effective in mature fields by improving production rates, reducing decline rates, and accessing bypassed oil. However, it also notes limitations including lack of control over drilling direction and inability to intervene if an undesirable zone is entered. The document recommends comparing results from a planned radial drilling project in India to the geological data from Imperial's wells before deciding to use it in Russia.
Subject: Feasibility of carrying out Radial drilling at imperial energy
This is in reference to the letter dated 22.05.13 from GM(D), OVL regarding carrying out of 'Radial Drilling' at Imperial Energy Projects in Russia to enhance production, on trial basis. It has been desired to have the opinion of IDT on trying out this technology in the above mentioned fields. Regarding the use of this technology, a presentation was made by Indian representative of M/s Radial Drilling Services on 27.05.2013 at IDT. After going through the presentation and examining the data available on the net regarding claims made by various vendors of this technology like Buckman jet drilling, Jet drilling WS, eSteams, Jereh ESC, ZRL, it is opined that Jet drilling/radial drilling is being effectively used to capture the benefits of horizontal drilling in smaller-scale reservoirs. It has been proven to enhance production rates, reduce decline rates, reduce near wellbore damage and recover more resources from mature wells, Also this technology can be used for deep acidization, Directional water injection to reduce injecting pressure and enhance impact, CO2 injection in place of SAGD in thick oil reservoir etc.. It involves drilling 1 to 2 lateral hole extending upto 300ft in length. However some company like JET drill refutes such claim and give realistic average length of lateral as 60 to 160ft only.The number of such radial holes is normally 3-4 from a particular depth after cutting holes in the casing using the same set of equipments.
The stability and straightness depend on formation characteristic like homogeneity and in situ stresses level. Currently no technology is commercially available to map or track the progress and placement of the Radials being drilled. A lateral can turn left -right or up -down after drilling a
loose/soft lump of formation.Also when a natural fracture is encountered , further drilling is not possible. Other constraint or limitations are:
Existing Perforations:No comments from any vendor as to what effect they will have on success of casing milling
Casing size. Currently available radial drilling equipment can operate in production casing sizes of 5 in. OD or greater. The equipment can also operate in 4-in. or greater in-gauge open hole.
Casing grade. The tungsten carbide bits used to mill casing exits are limited to casing grades of N-80Sand abrasion cutting limit not known (Russian grade D) or less. Casing wall thickness. The maximum casing wall thickness that the available casing cutters can mill is 10 mm (0.4 in.). Casing cementation. In order to successfully initiate a casing exit, radial drilling equipment requires a good cement bond between the casing and the formation. A poor casing bond generally results in difficulty or failure in jetting operations. The competence of the cement bond is generally assessed by cement bond logging. Wellbore inclination. Since the radial drilling system discussed here relies upon gravity to seat the radial drilling assembly in the deflector shoe, the well inclination should not exceed 60 from vertical. Wellbore depth. Currently available systems are designed to operate at a maximum depth of 3,000 m-3500m.. Porosity Min 3-4% Wellbore rathole. A rathole of at least 10 m (33 ft) is required to allow the jetted debris to settle beneath the deflector shoe. Bottomhole conditions. Operating temperatures at reservoir depth shouldnt exceed 120C (250F).Bottomhole pressure should not exceed 6,500 psi.
As such, the limitations associated with radial drilling technology are mainly no control over direction, managing production in case of undesirable zone entry, no possibility of intervention etc.
Oprerational sequences can be generally summarized as
WORK OVER RIG RJD UNIT & Accessories 1 Kill Well 2 Remove X-Mas & Install BOP 3 POOH Prd String, Packer 4 Clean hole, Scraper and bit trip 5 RIH Deflector tool on tubing 6
3
t o
5
d a y s
RIH gyro tool on wire line, engage with DeflectorUBHO 7 Ascertain Direction, rotate tubing to orient D-tool in desired direction
8 POOH Gyro ??? 9 RIH casing cutter, Cut hole in csg, pull cutter inside D/tool and rotate to next hole direction?? Or again gyro run required 10 POOH cutter . RIH jetting tool Jet dn laterals.POOH. CT, and tubibg with D/tool. R/DN CT unit etc. 11 RIH tubing w/completion assembly Remove BOP, install X-mas,Set Packer etc
12 Swabbing the well required to fully activate flow through radials
13 WELL CONTROL: TUBING CASING ANNULUS- RIG RESPOSIBILTY-contingency plan if Lubricator on CT fails Ct TUBING , Responsibility RJD
It is beyond the purview of IDT to comment on enhancement of production through such radially drilled laterals as it invoolves complex reservoir mechanics and production technology alternatives and overall economics. However, most of the vendors have claimed substantial gain in production through implementation of this technology in mature fields. As per literature survey, it appears that this technology is best suited for mature and depleted fields and most effective when vertical permeability is much higher than horizontal one.
It is understood that Radial drilling is going to be implemented in India in 4 wells of Gujarat of M/s SELAN in August/September 2013 and is expected to be completed in appox 1 month time. Therefore it is suggested that results of same can be compared with G & G data of imperial wells of before taking a decision regarding implementation of radial Drilling in Russia.
Applications of Radial Drilling Technology Radtech
Reverse declining production rates. Improve and extend drainage area in productive formations. Reach beyond the damaged area of the Well Bore. Improve the drainage. Produce heterogenous formations. Improve water injection. Improve vertical cleaning. Reduce water coning.
Regards,
( K Krishna Pratap)) ED-HOI-IDT
Well Selection Criteria Required technical information for a proper well selection: Electric logs CBL VDL CCL GR Rock mechanics DST and RFT results if available Well spacing Depth of interest ( producing formation) Thickness of the producing formation Mechanical integrity of casing W/O and O/G contacts Historical production data of oil, gas and water Previous optimization data (if any) Porosity and permeability data of the producing formation Hole deviation/inclination Type and weight of drilling fluid used BHT/BHP