PSS 02-434-858 - Dripless Shaft Seal 4 3/4", 8 5/8" Stern Tube

PSS 02-434-858 - Dripless Shaft Seal 4 3/4", 8 5/8" Stern Tube

The PSS 02-434-858 Dripless Shaft Seal is engineered for optimal performance in marine applications. This high-quality seal ensures a reliable and leak-free connection between the stern tube and the shaft, enhancing the longevity and efficiency of your vessel's propulsion system.

The Type B PSS Shaft Seal utilizes a mechanical face seal, where the sealing surface is formed between the flat surfaces of a rotating stainless-steel rotor and a stationary carbon flange. The carbon flange is securely attached to the bellows with hose clamps, while the back end of the bellows fits over the stern tube and is also secured with hose clamps. The stainless-steel rotor is mounted on the shaft in front of the carbon flange, compressing the bellows before being locked in place with set screws. This pre-load ensures consistent contact between the rotor and flange, allowing the PSS to adjust for any fore and aft movements caused by propeller thrust. Additionally, the carbon flange is designed to float around the shaft, accommodating misalignment and vibration issues. The rotor is sealed to the shaft with two O-rings that are recessed into the collar’s bore, which rotate with the shaft and rotor, minimizing wear during operation.

Specifications:

• Temperature Limits: -13°F to 425°F (-25°C to 220°C)
• Pressure Limits: 50 PSI (3.5 BAR)
• Shaft RPM Limits: 7,000 RPM
• Carbon Graphite: Lapped to 4 HLB (0.000044" tolerance)
• 316SS / Nitronic 50: Faced to 9-12 Ra
• Bellows Material: Mandrel formed silicone / fabric

Part Specifications:

• Part #: 02-434-858
• Shaft Diameter (A): 4-3/4"
• Stern Tube Diameter (B): 8-5/8" to 8-3/4"
• Approx. Length (C): 13.671"
• Approx. Compression: 1" to 1-1/4"
• Rotor Diameter (D): 7.875"
• Stern Cuff Length (E): 2.5"