جدایش زود هنگام پوشش پلی‌اتیلن سه لایه از سطح لوله و بررسی کارایی پوشش‌های جایگزین

نوع مقاله: مقاله پژوهشی

نویسندگان

پژوهشگاه صنعت نفت، پژوهشکده علوم وتکنولوژی پلیمر

چکیده

در این مقاله، جهت غلبه بر مشکل جدایش زود هنگام پوشش پلی‌اتیلن سه لایه از سطح، جایگزینی پوشش پلی‌اتیلن سه لایه با سایر پوشش‌ها مورد مطالعه قرار گرفته است. بر این اساس کارایی و کیفیت دو نمونه پوشش پلی‌یورتان و یک نمونه پوشش پلی اوره با اجرای آزمون‌های استاندارد چسبندگی، گسیختگی کاتدی، ضربه، خمش، جذب آب، سختی و استحکام دی الکتریک مورد بررسی و ارزیابی قرار گرفتند. نتایج آزمون گسیختگی کاتدی این سه نمونه با پوشش پلی اتیلن سه لایه مقایسه گردید. نتایج این بررسی نشان می‌دهد که مقاومت پوشش پلی یورتان به گسیختگی کاتدی نسبت به پلی اتیلن سه لایه بهتر است. پوشش‌های پلی‌یورتان اساساً سابقه گسیخته شدن (disbondment) از سطح، طی سرویس‌دهی را ندارند و با ضخامت‌هایی در حد یک سوم پلی اتیلن سه لایه قابل اعمال در سایت می‌باشند بنابراین، این مواد به عنوان یک جایگزین مناسب و مطلوب برای پلی‌اتیلن سه لایه توصیه می‌شوند. همچنین مشخص گردید که مقاومت به گسیختگی کاتدی پوشش پلی اوره با پلی‌اتیلن سه لایه قابل رقابت می‌باشد و بنا به همان دلایلی که برای پلی‌ یورتان ذکر شد این پوشش نیز می‌تواند به‌عنوان جایگزین مناسب برای پلی اتیلن سه لایه مورد توجه قرار گیرد.

کلیدواژه‌ها


عنوان مقاله [English]

Premature Disbondment of Three-layer PE Coating and Performance Investigation of its Probable Substitutes

نویسندگان [English]

  • Ahmad Nalbandi
  • Javad Heidarian
Polymer Science and Technology Division, Research Institute of Petroleum Industry (RIPI)
چکیده [English]

The mechanism and control of premature disbondment of three-layer polyethylene (3LPE) coatings have been the subjects of many research activities which are still going on. Also, the substitution of 3LPE with better coatings has been the aims of different research works and this paper is going to discuss it. Based on what is mentioned above, the quality and performance of two polyurethane and one polyurea coating samples were closely examined by running important standard tests including adhesion, cathodic disbondment, impact, bendability (flexibility), water absorption, surfaces hardness, and dielectric strength. The results of cathodic disbondment tests of these three samples were compared with that of 3LPE coating. In this research, it was shown that polyurethane had better cathodic disbondment results than 3LPE coating. With reference to the fact that there is no report in the literature on the early disbondment of polyurethane from pipe surface, and that the coating is applicable on-site with one third thickness of 3LPE, polyurethane is recommended as a suitable substitution for 3LPE. Moreover, it was found the cathodic disbondment result of the polyurea was comparable with that of 3LPE. With reference to the same reasons argued for polyurethane, polyurea can be a good substitute for 3LPE as well.

کلیدواژه‌ها [English]

  • Three-layer Polyethylene
  • Polyurethane
  • Polyurea
  • Premature Disbondment
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