Online Detection of Coiled Tubing Anomalies on a Small Scale for Safe CT Operations

摘要

Coiled tubing is a fast growing technology and is becoming an alternative to jointed pipe in a wide range of oil and gas well operations. The technology is pushed by the use of coiled tubing for complex operations that are safety, cost and environmentally sensitive. During operations the coiled tubing must retain its integrity under increasing conditions of pressure, load and depth. Since the tubing integrity is mainly determined by its physical properties, real-time inspection during operations is an excellent method to ensure safety and enhance reliability.AbstractSince the combination of measuring fatigue and corrosion in one system would be ideal but not possible for now, the best way to 'guard' the coiled tubing's integrity before or during operation, is to detect corrosion or other anomalies in a very early stage. Calculations on form and depth of CT anomalies to predict its growth and behavior still turn out to be very difficult. This means online detecting on a very small scale would give you a better and immediate view on the growing speed of anomalies and thus your total decay of the CT string. ROSEN does this by means of her well-known knowledge in the Magnetic Flux Leakage principle and her 20+ years experiencein pipeline inspections.For Hibernia Canada we introduced a new feature in our software concentrating on corrosion finding and wall thickness. We have divided the wall thickness into 9 different wall thickness part sections around the circumference. This means a more precise indication (and therefore better resolution) of the wall thickness part (40deg coverage each), which could contain a wall thinning including its clock position. Mechanical damage, corrosion parts or pits as small as approx 0.3mm (0.01") in depth can now be detected!