UV-Stabilized HDPE Outer Jacket with SS316 Bolting Assembly for Marine Pile Shielding

UV-Stabilized HDPE Outer Protective Jacket for Marine Pile Mechanical Shielding

The CNPetro PileCoat 2000F HDPE Outer Jacket is a modular protective jacket fabricated exclusively from seamless, UV-stabilized virgin high-density polyethylene sheeting. Engineered as the external mechanical shield within the PileCoat 2000F three-layer system, this tough outer shell provides the underlying anticorrosive tape layers with vital defense against wave action, drifting debris, mechanical impacts, and ultraviolet degradation.

Each jacket assembly includes M12 x 120 mm Hexagon Head SS316 Bolts, M12 A4 Self-Locking Nylon Insert Nuts, and dual M12 x 35 mm Penny Washers. Installation utilizes a specialized Hydraulic Tensioning Kit to achieve uniform bolting compression.

Material Engineering Data

Design Features for Marine Durability

• Seamless Virgin HDPE Construction: Fabricated from 100% virgin high-density polyethylene — no recycled or regrind content — ensuring consistent mechanical properties and long-term reliability without brittle fracture risks associated with reprocessed materials.
• UV Degradation Resistance: Carbon black content ≥ 2.0% per ASTM D1630 provides robust protection against ultraviolet radiation-induced polymer chain scission, maintaining mechanical integrity throughout decades of tropical sun exposure.
• Wave and Impact Defense: FTMS 101C puncture resistance ≥ 400 N shields the underlying corrosion protection layers from floating debris, ice scouring, vessel berthing impacts, and storm wave forces.
• Modular Design: Jacket sections can be positioned and tensioned independently, accommodating pile diameters up to 2.4 meters and simplifying logistics for remote offshore installation sites.
• SS316 Corrosion-Resistant Fasteners: All bolting hardware is fabricated from AISI 316 stainless steel with self-locking nylon insert nuts, eliminating the risk of galvanic corrosion or vibration-induced loosening in the splash zone.

Installation Using Hydraulic Tensioning

1. Positioning: Place the modular HDPE outercover sections over the tape-wrapped pile area, aligning the bolting bar channels.
2. Initial Compression: Insert M12 x 120 mm SS316 Hexagon Head Bolts through the bolting bars. Install dual M12 x 35 mm Penny Washers and M12 A4 Self-Locking Nylon Insert Nuts on each bolt.
3. Hydraulic Tensioning: Connect the specialized Hydraulic Tensioning Kit to the bolting bars. Gradually raise hydraulic pressure from 1500 psi to approximately 5000 psi, ensuring uniform compression across all bars.
4. Final Locking: Torque all nylon insert lock nuts to the specified value while the hydraulic pressure is maintained, then slowly release the tensioning kit.
5. Inspection: Verify uniform jacket compression and confirm all fasteners are fully engaged with no gaps between jacket edges.