(1) Steel pipes without pickling before pre-installation
(2) steel pipes that have been pickled but are seriously corroded
(1) degreasing using degreasing agent, remove the grease adhesion on the pipe
(2) Wash with clean water to remove dirt on the pipe
(3) rust removal in acid washing liquid to remove rust spots on the tube wall, rolled iron filings, etc.
(4) Washing and high-pressure water washing The attachments generated in the above operations should be washed with clean water, and the inside of the pipe should be washed with high-pressure water
(5) Neutralize the remaining acid on the pipe with lye
(6) Drying In order to effectively dry the pipe should be immersed in hot water or steam drying, should make the pipe dry
(7) rust prevention
(8) Check whether the pipe after pickling is clean
(9) Immediately after pickling, seal the opening part of the tube with plastic or plastic tape to avoid foreign matter and water intrusion
(1) Welding of pipes before pickling has been completed
(2) When disassembling, transporting and pickling, pay attention not to touch the pipeline, thread and sealing surface, and plug and seal with adhesive tape or plastic pipe
(3) Before pickling, welding slag, spatter and varnish on the pipe should be cleaned
(4) the thread parts of the application of plastic tape, rubber tape and other acid resistant materials to protect, or in degreasing, washing after the thread coated with dry oil and then in acid derusting, to prevent acid erosion
(5) When pickling, pay attention not to make the matching mark of the pipe disappear or blurred
