PSS 02-50M-312 - Dripless Shaft Seal 50 mm, 3 1/2" Stern Tube

PSS 02-50M-312 - Dripless Shaft Seal 50 mm, 3 1/2" Stern Tube

The PSS 02-50M-312 Dripless Shaft Seal is engineered for reliability and efficiency in marine applications. This innovative seal combines advanced materials and design to ensure optimal performance even under challenging conditions.

The Type A PSS Shaft Seal operates as a mechanical face seal, where the sealing surface is established between the flat surfaces of a rotating stainless-steel rotor and a stationary carbon flange. The carbon flange is securely attached to the bellows' front side using hose clamps, while the back end of the bellows fits over the stern tube, also secured with hose clamps. The stainless-steel rotor is mounted on the shaft, positioned just in front of the carbon flange. The rotor compresses the bellows before being fastened to the shaft with set screws. This pre-compression maintains consistent contact between the stainless-steel rotor and carbon flange, allowing the system to adjust for variable fore and aft movements caused by propeller thrust. Moreover, the carbon flange is over-bored to match the shaft diameter, enabling it to "float" around the shaft and effectively address most misalignment and vibration issues. Sealing is enhanced by two O-rings recessed within the collar's bore, which rotate with the shaft and stainless-steel rotor, ensuring minimal wear during operation.

Specifications:

• Temperature Limits: 5°F to 225°F (-15°C to 107°C)
• Pressure Limits: 15 PSI (1 BAR)
• Shaft RPM Limits: 10,000 RPM
• Carbon Graphite: Lapped to 4 HLB (0.000044" tolerance)
• 316SS / Nitronic 50: Faced to 9-12 Ra
• Bellows Material: Molded Nitrile - PVC

Part Information:

• Part #: 02-50M-312
• Shaft Diameter (A): 50mm
• Stern Tube Diameter (B): 3-1/2" to 3-5/8"
• Approx. Length (C): 9.03"
• Approx. Compression: 1"
• Rotor Diameter (D): 3.75"
• Stern Cuff Length (E): 2"