02-312-412 PSS Shaft Seal by PYI

#1 selling marine mechanical seal worldwide. Installed as standard equipment by the world’s most reputable boat builders / yards and the US Coast Guard. *ABS, RINA & Bureau Veritas Certified.

The PSS Shaft Seal is a mechanical face seal that is created between the flat surfaces of the rotating stainless steel rotor and the stationary carbon flange. The stationary carbon flange is attached to the vessels stern tube with hose clamps and the carbon flange is attached to the front side of the bellows with hose clamps. The stainless steel rotor is fit on the shaft in front of the carbon flange. The stainless steel rotor is used to compress the bellows before the collar is secured to the shaft with set-screws. This compression (pre-load) maintains contact between the faces and allows the PSS to compensate for the thrust from the propeller.

The carbon flange is bored larger than the shaft diameter allowing it to “float” around the shaft and thus compensate for most misalignment and vibration problems. The stainless steel collar is sealed to the shaft by two o-rings that are recessed into the bore of the collar. These o-rings rotate with the shaft and stainless steel rotor and do not experience wear during operation. 

02-312-412 Specifications 

Approx. Initial Compression: 1"
Approx. Length (A): 10.8625"
Rotor Diameter (B): 6"
Shaft Diameter (C): 3 1/2"
Stern Cuff Length (D): 2.5"
Stern Tube Diameter (E): 4 1/2" to 4 5/8"