The Cementing Technology Research And Application Of Xiaoji Area Of Dagang Oilfield

Xiaoji oil-bearing area set block of Dagang Oilfield12.46square kilometers, a Xiaoji set of development in the last century70’s oil fields, the cumulative oil production7600000tons. With the passage of time, Xiaoji oilfield has entered high water cut stage most blocks, an average of more than87%, productivity construction is more and more difficult. In order to improve the fault block control of well pattern, tapping the potential of reservoir, the various studies, from the completion and cementing quality of work, to know the old oil field, old block of recoverable reserves, and improve recovery. Practice has proved that does have effect. In cementing quality meet the requirements on the basis of Dagang Oilfield three plant for Xiaoji set oil rolling evaluation, the final selection of Xiaoji10-16region as a key object. After the technical staff, has carried on the revision of the regional structural interpretation, and set the evaluation well,20-12well, the well logging interpretation of reservoir thickness of115.6meters41. In2010, a Xiaoji set of block found new geological reserves of12840000tons, is1.6times more than30years of total output. As the largest reserves area of Dagang oilfield discovered in the past5years, ushered in a new reserves peak.In view of the above, in order to effectively improve the guarantee the cementing operation Xiaoji set block in Dagang Oilfield safety implementation and cementing quality, improve the optimization on cement slurry system and cementing technology and improved more and more attention by people, and have achieved some progress. Dagang Oilfield set block itself exists gypsum mudstone layer formation and biological limestone strata; and display the horizon, long well section, water pressure, and the infill development, formation pressure disturbance, the characteristics of interlayer channeling is serious, the cementing quality assurance more difficult.The topic for the Dagang Oilfield set there exist complex oil-water relationship, cementing long distance, Xiaoji cementing problem, research on the block of cement slurry system optimization technology research and field cementing system, Xiaoji set on the main factors affecting Xiaoji set block cementing quality, can effectively solve the cementing quality of salt formation, cement slurry top and bottom temperature, curing channeling condition.This subject mainly studies the influencing factors of Xiaoji field cementing quality, and analyzed, and the optimization of a Xiaoji set of blocks of cement slurry system. Specifically for Xiaoji field cementing technology to effectively solve the problem of cementing technology in Dagang Oilfield cementing operation, ensure the smooth implementation and cementing quality improvement, and the formation of matching technology. The research contents include:geological characteristics of Xiaoji set block; Xiaoji set block cementing difficulties and advantages analysis; analysis of creep stress of salt; Study on creep resistance of cement slurry system solid long letter of anti-channeling cement slurry system; salt resistance; cementing improve the replacement efficiency measures; Xiaoji set technology of cement block note.The key techniques:high pressure and low permeability formation cementing three pressure stability; excellent comprehensive properties of cement slurry system of salt rock, large temperature difference conditions; cementing fluid column structure of science, high replacement efficiency; targeted injection for construction parameters.Study on indexes:Xiaoji set block equivalent density cementing cement slurry weightlessness after each layer must be larger than the drilling fluid density is the section of the well; cementing salt layer of cement slurry thickening time must be greater than the construction time of more than80min; design of heavy slurry density is higher than0.25g/cm3in drilling fluid; turbulent prepad fluid contact time is more than7min; the field application in10-15wells, cementing qualification rate100%. Innovation:through the full investigation and analysis of the Xiaoji set of Dagang Oilfield Block, and a reasonable selection of Xiaoji set block in Dagang Oilfield cement slurry, which has anti-channeling performance is strong, has the very good flexural strength, can reduce the cement volume contraction, enhance and improve the bonding strength of cement sheath and casing and between the stratum, decrease the permeability of cement, reduce the comprehensive performance of cement slurry water loss, at the same time the field application and implementation in the technical measures of field matching process under the assistance, finally solve the Dagang Oilfield cementing technology problem set block complex oil and gas well cementing operation, ensure the smooth implementation and improve cementing quality of. Therefore, urgent need for research on the subject, the result has wide application prospect, service to the oil rate.