Tubing Length Measurement In Work Over Operation

In oil field work, most of the reservoir from the exploration into the development andmaintenance process in the late will greatly damage. Kill can cause reservoir pollution andcongestion, make the oil well production decline. Choke make local formation pressure isreduced, affect the reservoir capacity, damage the formation structure. Has certain harm to thedevelopment of oil and gas resources sustainable. Don’t kill operation technology can solvethese problems very well. Work under pressure to the annular blowout preventer are keycomponents in high temperature and high pressure in well implement isolation, when raisingor lowering string, the annular blowout preventer rubber core in the closed state, if there iscoupling through the annular blowout preventer rubber core in the open state, otherwise, willdamage the rubber core. If an annular blowout preventer rubber core open, another of theannular blowout preventer rubber core must be in a closed state, under the ascension or intothe tubing string, there will always be a closed annular blowout preventer, this completes thework under pressure. Therefore, accurately measure the location of the coupling in work overrig with pressure is very important. In this paper, by using grating measuring the length of thesingle tubing, effective application of the single-chip microcomputer control grating counts,the exact single tubing length, determines the location of the tubing coupling, for work overoperations, the opening of the annular blowout preventer, hydraulic tong provides the theorybasis for the location of the relative coupling. In oil field production, the length of the tubinghas caught the attention of work over rig personnel long-term, clear single tubing and overalllength of the tubing is a very important problem in the work over job. In this article can clearthe location of the tubing coupling can also clear tubing length. This method of measurementof tubing length has high measuring accuracy, reduce labor intensity, improve productionefficiency and economic benefit, etc.Paper based on the oilfield operations required for workover, design a kind of on-linedetection of coiled tubing length measurement system based on grating. The system through apair of grating pair of measuring the length of the tubing, designed for the wholemeasurement system hardware circuit and software program is developed. By measuringaccurately get single tubing length. By single-chip computer in order to store single tubing length can pinpoint the location of the tubing coupling.