Downhole Casing Flaw Combination Instrument Ground Information Collection System Is Developed

Precisely knowing the condition of casing damage contributes greatly to the research of on both its mechanism and reparation. For its advantages in providing complete image of casing detection, the electromagnetic defectscope and multi-arm caliper device are adopted by the oilfields for well operation and major overhaul: in addition to casing flaw detection qualitatively, MIT multi-arm caliper mainly characterize the inner surface of casing by calculating its inner diameter, while electromagnetic defectoscope is able to calculate wall thickness. When those two are used at the same time, both inner diameter and wall thickness can be obtained, by which the deformation of exterior surface can be determined. Then the basis of casing string design and production adjustment can be laid. The MIDK electromagnetic defectoscope and MIT028 multi-arm caliper are made by different companies with different mode of power supply and communication. This paper aims at providing with a combined test system, through which the MID_K and MIT028 can work at the same time. The logging time is saved and logging efficiency is enhanced for the test system acquired logging data in need at one time.The design of the test system is consisted of two parts about the develop of surface system for information collection and the design of the controller of logging tool. And the keystone of this task is the develop of surface system of information collection. The operation theory and bus structure of MIDK and MIT028 are introduced as the first part. The operation theory of logging tool (controller) XTU002, acted as the intelligent bridge of device bus Ultrawire and the telemetry system Ultralink of Sondex is introduced, followed by the introduction of design proposal of tool combination, the design scheme of MIDK control system, coding scheme of basic pulse in digital baseband signal transmission and protocol analysis on Ultralink/Ultralwire of Sondex. In the second part, the hardware design of surface system and MIDK control system are mainly expounded and the block diagram of hardware is illustrated with detailed description and analysis of the circuit unit. In the last part, there are brief introductions of PLD, CPLD,FPGA, EDA and VHDL, and the implementation of programmable logic design is provided.As a result of testing, the communication between the suface equipment and XTU002 is correct, transmission of data is no error ,capability of the surface equipmeng is stabilization.