Marine Hardware - Shaft Seals

PSS PRO Shaft Seal 2-1/4" Shaft  4" Tube [03-214-400]

PRO Shaft Seal 2-1/4" Shaft & 4" Tube

The PSS PRO Shaft Seal is a mechanical face seal utilizing our proven stainless steel and carbon sealing components but adds reinforced silicone bellows, a secondary shaft retention collar, 316 Stainless Steel hose clamps (rolled edges and non-perforated), and an optional Nitronic 50 rotor upgrade (for highly corrosive environments). Designed specifically for applications that will require increased durability and resistance to harsh, corrosive, high pressure, and otherwise demanding environments. The PSS PRO Shaft Seal is a specialized mechanical seal suitable for various applications, with unmatched performance.

As with PSS Type A & B Seals, The PRO Shaft Seal is a mechanical face seal. The sealing surface is created between the flat surfaces of the rotating stainless-steel rotor and the stationary carbon flange. The stationary carbon flange is attached to a heavy-duty silicone bellows attached to the vessel’s stern tube (shaft log), with 316SS hose clamps. The stainless-steel rotor is fitted on the shaft in front of the carbon flange and is used to compress the bellows, the rotor is then secured to the shaft with set screws, and the shaft retention collar is installed. This compression (pre-load) maintains constant contact between the two mating faces of the stainless-steel rotor and carbon flange, allowing the PSS to compensate for the variable axial movement due to propeller thrust. In addition, the carbon flange is over-bored to the shaft diameter allowing it to "float" around the shaft and thus compensate for most misalignment and vibration from the drive-line. The stainless-steel rotor is sealed to the shaft by two O-rings recessed into the rotor's bore. These O-rings rotate with the shaft and the stainless-steel rotor and therefore do not experience wear during operation.

Specifications:

• Temperature Limits: -13°F to 425°F (-25°C to 220°C)
• Pressure Limits: 40 PSI (2.75 BAR)
• Shaft RPM Limits: 10,000 RPM
• Carbon Graphite: Lapped to 4 HLB (0.000044" tolerance)
• 316SS / Nitronic 50: Faced to 9 Ra
• Bellow Material: Molded formed silicone / fabric

Product Dimensions:

• Shaft Dia. (A) 2-1/4"
• Stern Tube Dia. (B) 4" to 4-1/8"
• Uncompressed Length (C) 9.675" 
• Approx. Compressed Length 8.675"
• Rotor Diameter (D) 4.2"
• Stern Cuff Length (E) 1.3"

PSS PRO Shaft Seal 2-1/2" Shaft  3-1/2" Tube [03-212-312]

PSS Pro Shaft Seal - 2 1/2" Shaft & 3 1/2" Tube

The PSS PRO Shaft Seal is a mechanical face seal utilizing our proven stainless steel and carbon sealing components but adds reinforced silicone bellows, a secondary shaft retention collar, 316 Stainless Steel hose clamps (rolled edges and non-perforated), and an optional Nitronic 50 rotor upgrade (for highly corrosive environments). Designed specifically for applications that will require increased durability and resistance to harsh, corrosive, high pressure, and otherwise demanding environments. The PSS PRO Shaft Seal is a specialized mechanical seal suitable for various applications, with unmatched performance.

As with PSS Type A & B Seals, The PRO Shaft Seal is a mechanical face seal. The sealing surface is created between the flat surfaces of the rotating stainless-steel rotor and the stationary carbon flange. The stationary carbon flange is attached to a heavy-duty silicone bellows attached to the vessel’s stern tube (shaft log), with 316SS hose clamps. The stainless-steel rotor is fitted on the shaft in front of the carbon flange and is used to compress the bellows, the rotor is then secured to the shaft with set screws, and the shaft retention collar is installed. This compression (pre-load) maintains constant contact between the two mating faces of the stainless-steel rotor and carbon flange, allowing the PSS to compensate for the variable axial movement due to propeller thrust. In addition, the carbon flange is over-bored to the shaft diameter allowing it to "float" around the shaft and thus compensate for most misalignment and vibration from the drive-line. The stainless-steel rotor is sealed to the shaft by two O-rings recessed into the rotor's bore. These O-rings rotate with the shaft and the stainless-steel rotor and therefore do not experience wear during operation.

Specifications

• Temperature Limits: -13°F to 425°F (-25°C to 220°C)
• Pressure Limits: 40 PSI (2.75 BAR)
• Shaft RPM Limits: 10,000 RPM
• Carbon Graphite: Lapped to 4 HLB (0.000044" tolerance)
• 316SS / Nitronic 50: Faced to 9 Ra
• Bellow Material: Molded formed silicone / fabric

Product Dimensions

• Shaft Dia. (A) 2-1/2"
• Stern Tube Dia. (B) 3-1/2" to 3-5/8"
• Uncompressed Length (C) 9.800" 
• Approx. Compressed Length 8.800" 
• Rotor Diameter (D) 4.2"
• Stern Cuff Length (E) 1.3"

PSS PRO Shaft Seal 2-1/2" Shaft  4" Tube [03-212-400]

PRO Shaft Seal 2-1/2" Shaft & 4" Tube

The PSS PRO Shaft Seal is a mechanical face seal utilizing our proven stainless steel and carbon sealing components but adds reinforced silicone bellows, a secondary shaft retention collar, 316 Stainless Steel hose clamps (rolled edges and non-perforated), and an optional Nitronic 50 rotor upgrade (for highly corrosive environments). Designed specifically for applications that will require increased durability and resistance to harsh, corrosive, high pressure, and otherwise demanding environments. The PSS PRO Shaft Seal is a specialized mechanical seal suitable for various applications, with unmatched performance.

As with PSS Type A & B Seals, The PRO Shaft Seal is a mechanical face seal. The sealing surface is created between the flat surfaces of the rotating stainless-steel rotor and the stationary carbon flange. The stationary carbon flange is attached to a heavy-duty silicone bellows attached to the vessel’s stern tube (shaft log), with 316SS hose clamps. The stainless-steel rotor is fitted on the shaft in front of the carbon flange and is used to compress the bellows, the rotor is then secured to the shaft with set screws, and the shaft retention collar is installed. This compression (pre-load) maintains constant contact between the two mating faces of the stainless-steel rotor and carbon flange, allowing the PSS to compensate for the variable axial movement due to propeller thrust. In addition, the carbon flange is over-bored to the shaft diameter allowing it to "float" around the shaft and thus compensate for most misalignment and vibration from the drive-line. The stainless-steel rotor is sealed to the shaft by two O-rings recessed into the rotor's bore. These O-rings rotate with the shaft and the stainless-steel rotor and therefore do not experience wear during operation.

Specifications:

• Temperature Limits: -13°F to 425°F (-25°C to 220°C)
• Pressure Limits: 40 PSI (2.75 BAR)
• Shaft RPM Limits: 10,000 RPM
• Carbon Graphite: Lapped to 4 HLB (0.000044" tolerance)
• 316SS / Nitronic 50: Faced to 9 Ra
• Bellow Material: Molded formed silicone / fabric

Product Dimensions:

• Shaft Dia. (A) 2-1/2"
• Stern Tube Dia. (B) 4" to 4-1/8"
• Uncompressed Length (C) 9.800" 
• Approx. Compressed Length 8.800" 
• Rotor Diameter (D) 4.2"
• Stern Cuff Length (E) 1.3"

PSS PRO Shaft Seal 3" Shaft  4-1/2" Tube [03-300-412]

Ships Direct From Manufacturer 

PRO Shaft Seal 3" Shaft & 4-1/2" Tube

The PSS PRO Shaft Seal is a mechanical face seal utilizing our proven stainless steel and carbon sealing components but adds reinforced silicone bellows, a secondary shaft retention collar, 316 Stainless Steel hose clamps (rolled edges and non-perforated), and an optional Nitronic 50 rotor upgrade (for highly corrosive environments). Designed specifically for applications that will require increased durability and resistance to harsh, corrosive, high pressure, and otherwise demanding environments. The PSS PRO Shaft Seal is a specialized mechanical seal suitable for various applications, with unmatched performance.

As with PSS Type A & B Seals, The PRO Shaft Seal is a mechanical face seal. The sealing surface is created between the flat surfaces of the rotating stainless-steel rotor and the stationary carbon flange. The stationary carbon flange is attached to a heavy-duty silicone bellows attached to the vessel’s stern tube (shaft log), with 316SS hose clamps. The stainless-steel rotor is fitted on the shaft in front of the carbon flange and is used to compress the bellows, the rotor is then secured to the shaft with set screws, and the shaft retention collar is installed. This compression (pre-load) maintains constant contact between the two mating faces of the stainless-steel rotor and carbon flange, allowing the PSS to compensate for the variable axial movement due to propeller thrust. In addition, the carbon flange is over-bored to the shaft diameter allowing it to "float" around the shaft and thus compensate for most misalignment and vibration from the drive-line. The stainless-steel rotor is sealed to the shaft by two O-rings recessed into the rotor's bore. These O-rings rotate with the shaft and the stainless-steel rotor and therefore do not experience wear during operation.

Specifications:

• Temperature Limits: -13°F to 425°F (-25°C to 220°C)
• Pressure Limits: 40 PSI (2.75 BAR)
• Shaft RPM Limits: 10,000 RPM
• Carbon Graphite: Lapped to 4 HLB (0.000044" tolerance)
• 316SS / Nitronic 50: Faced to 9 Ra
• Bellow Material: Molded formed silicone / fabric

Product Dimensions:

• Shaft Dia. (A) 3"
• Stern Tube Dia. (B) 4-1/2" to 4-5/8" 
• Uncompressed Length (C) 9.800" 
• Approx. Compressed Length 8.800" 
• Rotor Diameter (D) 5"
• Stern Cuff Length (E) 1.3"

PSS PRO Shaft Seal 2" Shaft  3-1/2" Tube [03-200-312]

PRO Shaft Seal 2" Shaft & 3-1/2" Tube

The PSS PRO Shaft Seal is a mechanical face seal utilizing our proven stainless steel and carbon sealing components but adds reinforced silicone bellows, a secondary shaft retention collar, 316 Stainless Steel hose clamps (rolled edges and non-perforated), and an optional Nitronic 50 rotor upgrade (for highly corrosive environments). Designed specifically for applications that will require increased durability and resistance to harsh, corrosive, high pressure, and otherwise demanding environments. The PSS PRO Shaft Seal is a specialized mechanical seal suitable for various applications, with unmatched performance.

As with PSS Type A & B Seals, The PRO Shaft Seal is a mechanical face seal. The sealing surface is created between the flat surfaces of the rotating stainless-steel rotor and the stationary carbon flange. The stationary carbon flange is attached to a heavy-duty silicone bellows attached to the vessel’s stern tube (shaft log), with 316SS hose clamps. The stainless-steel rotor is fitted on the shaft in front of the carbon flange and is used to compress the bellows, the rotor is then secured to the shaft with set screws, and the shaft retention collar is installed. This compression (pre-load) maintains constant contact between the two mating faces of the stainless-steel rotor and carbon flange, allowing the PSS to compensate for the variable axial movement due to propeller thrust. In addition, the carbon flange is over-bored to the shaft diameter allowing it to "float" around the shaft and thus compensate for most misalignment and vibration from the drive-line. The stainless-steel rotor is sealed to the shaft by two O-rings recessed into the rotor's bore. These O-rings rotate with the shaft and the stainless-steel rotor and therefore do not experience wear during operation.

Specifications:

• Temperature Limits: -13°F to 425°F (-25°C to 220°C)
• Pressure Limits: 40 PSI (2.75 BAR)
• Shaft RPM Limits: 10,000 RPM
• Carbon Graphite: Lapped to 4 HLB (0.000044" tolerance)
• 316SS / Nitronic 50: Faced to 9 Ra
• Bellow Material: Molded formed silicone / fabric

Product Dimensions:

• Shaft Dia. (A) 2"
• Stern Tube Dia. (B) 3-1/2" to 3-5/8"
• Uncompressed Length (C) 9.268" 
• Approx. Compressed Length 8.268" 
• Rotor Diameter (D) 3.75"
• Stern Cuff Length (E) 1.3"

PSS PRO Shaft Seal 1-3/4" Shaft  3-1/2" Tube [03-134-312]

PRO Shaft Seal 1-3/4" Shaft & 3-1/2" Tube

The PSS PRO Shaft Seal is a mechanical face seal utilizing our proven stainless steel and carbon sealing components but adds reinforced silicone bellows, a secondary shaft retention collar, 316 Stainless Steel hose clamps (rolled edges and non-perforated), and an optional Nitronic 50 rotor upgrade (for highly corrosive environments). Designed specifically for applications that will require increased durability and resistance to harsh, corrosive, high pressure, and otherwise demanding environments. The PSS PRO Shaft Seal is a specialized mechanical seal suitable for various applications, with unmatched performance.

As with PSS Type A & B Seals, The PRO Shaft Seal is a mechanical face seal. The sealing surface is created between the flat surfaces of the rotating stainless-steel rotor and the stationary carbon flange. The stationary carbon flange is attached to a heavy-duty silicone bellows attached to the vessel’s stern tube (shaft log), with 316SS hose clamps. The stainless-steel rotor is fitted on the shaft in front of the carbon flange and is used to compress the bellows, the rotor is then secured to the shaft with set screws, and the shaft retention collar is installed. This compression (pre-load) maintains constant contact between the two mating faces of the stainless-steel rotor and carbon flange, allowing the PSS to compensate for the variable axial movement due to propeller thrust. In addition, the carbon flange is over-bored to the shaft diameter allowing it to "float" around the shaft and thus compensate for most misalignment and vibration from the drive-line. The stainless-steel rotor is sealed to the shaft by two O-rings recessed into the rotor's bore. These O-rings rotate with the shaft and the stainless-steel rotor and therefore do not experience wear during operation.

Specifications:

• Temperature Limits: -13°F to 425°F (-25°C to 220°C)
• Pressure Limits: 40 PSI (2.75 BAR)
• Shaft RPM Limits: 10,000 RPM
• Carbon Graphite: Lapped to 4 HLB (0.000044" tolerance)
• 316SS / Nitronic 50: Faced to 9 Ra
• Bellow Material: Molded formed silicone / fabric

Product Dimensions:

• Shaft Dia. (A) 1-3/4"
• Stern Tube Dia. (B) 3-1/2" to 3-5/8"
• Uncompressed Length (C) 9.268" 
• Approx. Compressed Length 8.268" 
• Rotor Diameter (D) 3.75"
• Stern Cuff Length (E) 1.3"

PSS PRO Shaft Seal 2" Shaft  3" Tube [03-200-300]

PRO Shaft Seal 2" Shaft & 3" Tube

The PSS PRO Shaft Seal is a mechanical face seal utilizing our proven stainless steel and carbon sealing components but adds reinforced silicone bellows, a secondary shaft retention collar, 316 Stainless Steel hose clamps (rolled edges and non-perforated), and an optional Nitronic 50 rotor upgrade (for highly corrosive environments). Designed specifically for applications that will require increased durability and resistance to harsh, corrosive, high pressure, and otherwise demanding environments. The PSS PRO Shaft Seal is a specialized mechanical seal suitable for various applications, with unmatched performance.

As with PSS Type A & B Seals, The PRO Shaft Seal is a mechanical face seal. The sealing surface is created between the flat surfaces of the rotating stainless-steel rotor and the stationary carbon flange. The stationary carbon flange is attached to a heavy-duty silicone bellows attached to the vessel’s stern tube (shaft log), with 316SS hose clamps. The stainless-steel rotor is fitted on the shaft in front of the carbon flange and is used to compress the bellows, the rotor is then secured to the shaft with set screws, and the shaft retention collar is installed. This compression (pre-load) maintains constant contact between the two mating faces of the stainless-steel rotor and carbon flange, allowing the PSS to compensate for the variable axial movement due to propeller thrust. In addition, the carbon flange is over-bored to the shaft diameter allowing it to "float" around the shaft and thus compensate for most misalignment and vibration from the drive-line. The stainless-steel rotor is sealed to the shaft by two O-rings recessed into the rotor's bore. These O-rings rotate with the shaft and the stainless-steel rotor and therefore do not experience wear during operation.

Specifications:

• Temperature Limits: -13°F to 425°F (-25°C to 220°C)
• Pressure Limits: 40 PSI (2.75 BAR)
• Shaft RPM Limits: 10,000 RPM
• Carbon Graphite: Lapped to 4 HLB (0.000044" tolerance)
• 316SS / Nitronic 50: Faced to 9 Ra
• Bellow Material: Molded formed silicone / fabric

Product Dimensions:

• Shaft Dia. (A) 2"
• Stern Tube Dia. (B) 3" to 3-1/8"
• Uncompressed Length (C) 9.268" 
• Approx. Compressed Length 8.268" 
• Rotor Diameter (D) 3.75"
• Stern Cuff Length (E) 1.3"

PSS Shaft Seal 3" Shaft - 5-1/2" Stern Tube [02-300-512]

Ships Direct From Manufacturer 

3" Shaft - 5-1/2" Stern Tube

The PSS Shaft Seal is the #1 selling marine mechanical seal worldwide and is installed as standard equipment by many of the worlds most reputable boat builders and boat yards. The PSS Shaft Seal is also recognized as the premiere retrofit (aftermarket) seal on the world market. Boat builders and boat yards recognize the advantages and value of installing the PSS as it eliminates the maintenance, constant adjustment & cost associated with traditional packing type glands. Aside from these benefits, the PSS Shaft Seal helps to eliminate water in the bilge (100% water tight) & wear to the propeller shaft. 

How Does it Work?

1. Two nitrile o-rings seal the stainless steel rotor to the shaft and will not experience wear.

2. A primary set screw and a backup set screw (2 sets) are used to secure the stainless steel rotor to the shaft.

3. A seal is created between the two flat surfaces of the carbon stator and the stainless steel rotor.

4. Water is fed into the PSS Shaft Seal for cooling/lubricating the seal faces on high speed vessels.

5. The stationary carbon stator is attached to the nitrile bellow, which is attached to the stern tube (shaft log).

Rotor

The PSS stainless steel rotor is slid down the shaft and is secured to the shaft with set screws at 90° for maximum holding power. Precision tolerances are maintained by computer controlled lathes. The faces have a number 9 micro finish and are perpendicular to the bore to prevent run-out as the collar rotates. The carbon graphite stator will polish the face of the rotor during the first few minutes of operation. The stainless steel rotor should not need to be replaced under normal operating conditions. The stainless steel rotor used on the PSS Type A Shaft Seal is made from 316L stainless steel. 

Carbon Stator

The high density, resin impregnated carbon/graphite stator is a composite that is first mixed, molded and then formed under pressure. The blanks are then baked, machined and lapped. The face of our carbon is finished to a flatness of 4 helium light bands (measured .000044" of variation over entire lapped surface). The grade of carbon used in the PSS has an operating temperature over 500° Fahrenheit (+260° Celsius), and cannot melt if the seal runs dry, unlike a rubber lip seal or plastic face seal. The high density of the carbon greatly increases the longevity and wear resistance. Several commercial vessels have recorded over 40,000 (over 4-1/2 years of continuous operation) engine hours on the same, original components. The carbon should not need to be replaced under normal operating conditions. 

Bellow

The PSS Type A Shaft Seal bellow is made from rubber (Nitrile), and has a temperature rating of -25°F to +225°F (-31°C to +107°C). Nitrile is known for its resistance to weathering. Nitrile rubber is exceptionally resistant to oils and non-polar solvents. It also offers good gas impermeability, abrasion resistance, and better thermal stability than most general purpose elastomers. 

Hose Barb

For high speed vessels it is required that a positive water supply be plumbed to the PSS Shaft Seal for the purpose of lubricating and cooling the seal faces. There are many sources of water supply, review the PSS Shaft Seal Installation Instructions for more information and note all plumbing must follow the standards and practices of proper boat plumbing. In most cases a slow speed boat that does not have a bearing the shaft log does not require positive water feed and can simply be "vented". Ideally the vent line will be run at least 2-3 feet above the water line and is close to the center line as possible to ensure the vent hose is never below the water line, even if the boat heels. Review the PSS Shaft Seal Installation Instructions for more details on venting the seal.