| As prolong of exploitation time on Daqing oilfield and implementation of secondary and thrice dense exploration schemes, the more complicated the underground conditions in the oilfield become, the more channeling wells are found. The exploration-layer systems are interrupted by the channeling, especially the multilayer-section channeling wells, and severely interference among layers are caused. Original chemical sealing methods are not adaptive to sealing the multilayer-section channeling wells due to performance of the sealing dosage and the technology application conditions. Accordingly, new sealing technologies are required.Through in-door test determined the cement additive agent types. For after-cement property evaluating , optimum suitable different channeling wells cement formulation , secure plugging channel quality . Through theory study , in-door test and in-site experiment, determined suitable Daqing oilfield multi-zones channeling wells perforation , channeling pre-treatment, cementing plugging drill and mill etc. technology . Finally forming match technology on multi-channeling zones cement plugging . In-door experiment and 28 wells in-site test demonstration that the cement plugging formulation with right angle thickening agent, micro-swelling and addable plugging agent , and with the center of"pressure waiting-on-cement"technology on long interval cement channeling plugging.The technology are simple , high successful ratio , and have advantage of low damage on reservoir , short operation period , high safety , no channeling detection, relative cost low etc. It can plug long interval, multipoint discontinuous channeling wells. Difficulties on dealing with multilayer-section channeling well are solved, casing damage wearing out is reduced, layer system is released, reserves which can be explored is increased and injected water or polymer entering into nonobjective layers are solved, which has excellent popularizing value and application foreground.
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