DEVELOPMENT OF BIG DIAMETER GLASS-STEEL INNER BARREL FORM-KEEPING CORING TOOL

The big diameter glass - steel inner barrel form - keeping coring tool which our institute has developed increases the core intensity by augmenting the diameter of core.It can also increase the core shape and core recovery. By chosing the glass -steel inner barrel to replace the former steel inner barrel,it decrease the resistance of core entering inner barrel in the process of the core drilling,and it also decreases the loss of core caused by the blocking or abrading core.Therefore,it ensure the rate of core shape and the normal mechanical speed of coring.Meanwhile,the the glass - steel inner barrel can be cut and refrigerated when core is taken out,and the sample rate of the unconsolidated core is increased.The coring tool has been applied in the Karamay、Kazakhstan and Tuha oilfield,and it has improved many technic factor such as the average core shape and recovery,etc,and gained well combined benefits.The paper introduces briefly several key factors during developing the coring tools.