PSS 02-20M-134 - Dripless Shaft Seal 20 mm, 1 3/4" Stern Tube

PSS 02-20M-134 - Dripless Shaft Seal 20 mm, 1 3/4" Stern Tube

The PSS 02-20M-134 Dripless Shaft Seal is designed to provide reliable sealing for marine applications. This innovative mechanical face seal utilizes a unique design for optimal performance and longevity.

The Type A PSS Shaft Seal features a mechanical face seal that creates a sealing surface between the flat surfaces of a rotating stainless-steel rotor and a stationary carbon flange. The carbon flange is securely attached to the front of the bellows using hose clamps, while the rear of the bellows fits snugly over the stern tube, also secured with hose clamps. The stainless-steel rotor is mounted on the shaft in front of the carbon flange, compressing the bellows to maintain a constant contact between the rotor and flange. This pre-load allows the PSS to effectively accommodate any fore and aft movement caused by propeller thrust.

Moreover, the carbon flange is over-bored to match the shaft diameter, enabling it to “float” around the shaft and mitigate misalignment and vibration issues. The stainless-steel rotor is sealed to the shaft by two O-rings that are recessed into the collar's bore. These O-rings rotate with the shaft and rotor, ensuring minimal wear during operation.

Key specifications include:

• 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

Specifications:

• Part #: 02-20M-134
• Shaft Diameter (A): 20 mm
• Stern Tube Diameter (B): 1-3/4" to 1-7/8"
• Uncompressed Length (C): 6.75"
• Approx. Compression: 3/4"
• Rotor Diameter (D): 2.375"
• Stern Cuff Length (E): 1.5"