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T: +86-156-0511-1716
E: hp018@hpcbkj.com
E: hp018@hpcbkj.com
In Fangong Industrial Park, Dongtai Town, Dongtai City
This specialized seal plays a critical role in ship stern shaft systems. It prevents seawater intrusion while ensuring reliable shaft operation under water-lubricated conditions.
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The Oil Lubrication Stern Shaft Sealing Apparatus is a specialized sealing solution for marine stern shafts operating with oil as the working medium. It effectively prevents seawater intrusion and lubricating oil leakage, ensuring stable operation of stern shaft systems in various marine environments. Available in multiple models (e.g., HPQ2, HPH3, HPH4, HPH3F), it caters to diverse vessel sizes and operating conditions.
Multi-Model Adaptability: Offers models with special functions (F: sand-proof ring, D: sundry-blocking ring, W: fishing net prevention) to address specific environmental challenges (e.g., sandy coastal waters, fishing areas).
Wide Operating Range: Suitable for stern shaft diameters of 50–1150mm, with a temperature tolerance of -25°C to +110°C and a maximum shaft line speed of 7m/sec—adapting to most commercial vessels.
Low Leakage Performance: Maintains an average leakage rate of 5–30ml/h, minimizing oil waste and environmental impact.
Dual-Seal Reliability: Combines pneumatic sealing (static shaft) and mechanical dynamic sealing (rotating shaft) to ensure leak-proof performance in all operating states.
Reinforced Pneumatic Tube: Equipped with an inner reinforcement ring to prevent deformation under high air pressure, ensuring reliable static sealing.
Precision Seal Ring Matching: Static and dynamic rings are made of wear-resistant materials (e.g., carbon graphite) with ultra-smooth contact surfaces (Ra ≤0.8μm) for long-term sealing performance.
Impurity-Resistant Designs: Models with F (sand-proof), D (sundry-blocking), or W (fishing net prevention) functions protect the sealing system from marine debris, reducing wear and failure risks.
Pressure Balance Optimization: The seal design and air pressure control system balance internal oil pressure and external seawater pressure, minimizing leakage and extending seal life.
Inland Oil-Carrying Vessels: HPQ2 forward seals and HPH3 aft seals prevent oil leakage into rivers, complying with inland water environmental regulations.
Coastal Fishing Boats: HPH3F (sand-proof) models resist sand and sediment in shallow coastal waters, reducing seal replacement frequency.
Offshore Wind Farm Vessels: HPH4DW (fishing net prevention) models avoid seal damage from floating fishing nets, ensuring continuous operation for wind turbine maintenance.
Large Oil Tankers: High-performance HPH4 models handle high shaft speeds (up to 7m/sec) and heavy loads, providing stable sealing for long-haul oil transportation.
Seal Seat: Anchors the entire apparatus to the hull or stern tube, with precise machining to ensure alignment with the stern shaft.
Pneumatic Tube: Made of high-elastic rubber with an inner reinforcement ring; inflates with compressed air to block axial seawater intrusion when the shaft is stationary.
Seal Ring Assembly:
Static Ring: Fixed to the seal seat, with a corrosion-resistant coating to withstand oil and seawater exposure.
Dynamic Ring: Mounted on a rotating seat connected to the stern shaft; moves axially with the shaft to maintain contact with the static ring.
Spring: Installed between the dynamic ring seat and bushing to provide constant pressure, compensating for seal wear and shaft vibration.
O-Ring: Made of nitrile rubber (NBR) or fluororubber (FKM) for oil resistance; installed at the seat-static ring, dynamic ring seat-bushing, and pipe joints.
Pipe Joints:
Inflation Port: Connects to the ship’s compressed air system to supply air to the pneumatic tube.
Cooling Water Port: Circulates cooling water to reduce heat from the rotating dynamic ring and shaft.
At Rest (Pneumatic Sealing): When the stern shaft stops, compressed air (1–2bar) is injected into the pneumatic tube, inflating the rubber sleeve to form a tight seal against the shaft—blocking axial seawater entry.
In Operation (Dynamic Sealing): As the shaft rotates, the spring pushes the dynamic ring to maintain intimate contact with the static ring; the rotating seal face blocks radial seawater leakage. O-rings seal auxiliary paths (e.g., between the seal seat and static ring).
Pressure Balance Mechanism: The system adjusts the pneumatic tube’s air pressure to match the external seawater pressure and internal oil pressure, avoiding seal deformation or leakage caused by pressure differentials.
For a sealing apparatus with a 220mm liner outer diameter, 3 aft seal rings, and a sand-proof ring:
Forward Stern Shaft Sealing Apparatus: HPQ2-220
Aft Stern Shaft Sealing Apparatus: HPH3F-220
Model Selection Guidance: Provides personalized model recommendations based on vessel type (e.g., tanker, fishing boat), operating area (e.g., coastal, offshore), and stern shaft parameters (diameter, speed).
Custom Material Options: Offers seal ring materials (e.g., carbon graphite, silicon carbide) and O-ring materials (FKM for high temperature, NBR for general use) based on operating conditions.
Installation Drawings & Manuals: Supplies detailed 2D assembly drawings, 3D models, and step-by-step installation guides to ensure correct integration.
After-Sales Warranty: Provides a 12-month warranty for the main apparatus, with free replacement of defective parts (excluding wear parts) within the warranty period.
Spare Parts Supply: Maintains a global inventory of common spare parts (e.g., dynamic rings, O-rings, pneumatic tubes) for fast delivery to ports worldwide.
