Page 97 - Pipeline Pigging Technology

Pipeline Pigging Technology

tool to recognize them. The table has been formulated as a result of two
studies performed by Pag-O-Flex for Norwegian oil companies, and as a result
of canvassing more than 60 NDT equipment operators.
The effects identified in the table are a result of changes in the pipe
structure caused by the presence of defects. The techniques listed are those
which have been short-listed as being reliable because of (a) prior industry
experience; (b) manufacturer experience; or, (c) because they have been
used to inspect similar composite structures with a degree of success.
What has been clear from previous studies is that improvements in noise
filters, enhancement of backscatter techniques, and better live imaging
techniques, are required to make market-available equipment fully ready to
undertake flexible pipe inspection. A closer co-operation is also required
between pipe manufacturer and equipment supplier in order to develop a
system for defect recognition and classification if this technology is to
establish itself alongside that of rigid pipe inspection.

REFERENCES

1. American Petroleum Institute, 1987. Recommended practice for flexible
pipe RP 17b. API, October, Houston.
2. R.G.Bea, FJ.Puskar, C.Smith and J.S.Spencer, 1988. Development of AIM-
programmes for fixed and mobile platforms. Proc.OTC 5703, May, Hou-
ston.
3. R.MJamieson, 1986. Pipeline Monitoring. Proc. Pipeline Integrity Monitor-
ing Conf., Pipes & Pipelines International, October, Aberdeen.
4. C. Le Floc'h, 1986. Acoustic emission monitoring of composite high-
pressure fluid storage tanks. NDT International, 19, 4, Houston.
5. Y.Makino, T.Okamoto, Y.Goto and M.Araki, 1989. The problem of gas
permeation in flexible pipe. Proc. OTC 5745, May, Houston.
6.J.M.Neffgen, 1988. Integrity monitoring of flexible pipes. Pipes & Pipelines
International, 33, 3, May/June.
7. J.M.Neffgen, 1989. New developments in the inspection and monitoring of
flexible pipes. Proc. Subtech '89 Conf., November, Aberdeen.
8. Pag-O-Flex, 1987. Joint industry report on fatigue of flexible pipes, Decem-
ber, Dusseldorf.
9. J.L.Rose, 1984. Ultrasonic wave propagation principles in composite
material inspection. ASNT Materials Evaluation No. 43, April.
10. Veritec, 1987. Guidelines for flexible pipe design and construction, Joint
Industry Project, JIP/GFP-02, Oslo.

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