Polyethylene Pipeline Coating Tape Construction Method
Polyethylene Pipeline Coating Tape ( PE Pipe Coated Tape ) Construction Method
Steel Pipe Surface Treatment:
1. Before Derusting The Steel Pipe Surface, The Welding Slag And Burr On The Steel Pipe Surface Shall Be Removed. The Oil And Impurities Adhered On The Surface Of Steel Pipe Shall Be Removed By Proper Methods. Before Rust Removal, The Surface Temperature Of Steel Pipe Shall Be More Than 3 ℃ Higher Than The Dew Point Temperature.
2. Spray Derusting Method Should Be Adopted For Steel Pipe Surface Derusting. When Spray Derusting Is Adopted, The Derusting Grade Shall Reach Sa2 Specified In The Current National Standard "Surface Treatment Of Steel Pipes Before Application Of Coatings - Visual Evaluation Of Surface Cleanliness - Part 1: Corrosion Grades And Treatment Grades Of Uncoated Steel Surfaces And Steel Surfaces After Overall Removal Of Original Coatings" (Gb / T 8923.1) ½ Grade 1; When Restricted By Site Construction Conditions, Power Tools Can Be Used To Remove Rust. When The Electric Tool Derusting Method Is Adopted, The Derusting Grade Shall Reach The St3 Grade Specified In The Current National Standard Gb / T 8923.1 "Surface Treatment Of Steel Pipes Before Coating - Visual Evaluation Of Surface Cleanliness - Part 1: Derusting Grade And Treatment Grade Of Uncoated Steel Surfaces And Steel Surfaces After Overall Removal Of The Original Coating"
3. After Rust Removal, The Sharp Part That May Stab The Anticorrosive Coating Shall Be Polished. And The Abrasives And Dust Adhered On The Metal Surface Are Removed. The Surface Dust Level Shall Meet The Quality Requirements Of Grade 3 And Above Specified In The Current National Standard Gb / T 18570.3 "Surface Treatment Of Steel Pipes Before Application Of Paints - Experiment For Assessment Of Surface Cleanliness - Part 3: Dust Assessment Of Steel Pipe Surface Before Application Of Paints (Pressure Sensitive Adhesive Tape Method)".
4. The Time Interval Between Steel Pipe Surface Treatment And Primer Application Should Be Controlled Within 1 h, During Which The Surface Of Steel Pipe Should Be Protected From Moisture And Pollution. The Surface Treatment Shall Be Carried Out Again In Case Of Rust Or Surface Contamination Before Primer Application.
Primer Application:
1. Mix The Primer Evenly Before Use.
2. Apply The Primer According To The Primer Instruction Provided By The Manufacturer. The Primer Shall Be Applied Evenly, And No Defects Such As Missed Coating, Clot And Sagging Are Allowed.
3. Avoid Surface Contamination Before Winding The Tape.
Polyethylene Pipeline Coating Tapes Winding:
1. Unwind According To The Conditions Specified In The Adhesive Tape Instruction.
2. Special Winding Machine Or Manual Winding Machine Should Be Used For Winding Construction. When Winding The Adhesive Tape, The Filler Material Matching The Adhesive Tape Should Be Used On Both Sides Of The Weld. When Spiral Welded Pipe Is Wound With Adhesive Tape, The Winding Direction Of Adhesive Tape Shall Be Consistent With The Welding Direction.
3. When The Machine Is Used For Winding, The Tension On The Winding Tool Shall Be Adjusted, The Uniform Tension Shall Be Applied To The Adhesive Tape, And The Adhesive Tape Shall Be Wound On The Primed Steel Pipe According To The Overlapping Requirements. The Overlapping Length At The Beginning And End Of The Adhesive Tape Shall Not Be Less Than 1 / 4 Of The Circumference Of The Pipe, And Not Less Than 100 Mm. The Lap Joint Of Two Winding Should Be Staggered. The Lap Width Shall Not Be Less Than 25 Mm. When Winding, The Lap Joint Of The Adhesive Tape Should Be Parallel, Not Twisted And Folded, And The End Of The Tape Should Be Pressed, Not Cocked.
4. Factory Prefabricated Polyolefin Adhesive Tape Anti-Corrosion Coating, Pipe End Application Of 150 Mm ± 10 Mm.
5. The Anti-Corrosion Of Pipe Fittings Can Be Carried Out By Hand Winding. It Should Be Filled With Matching Materials Before Winding.
