Allpa TMF Axial Mechanical Propeller Shaft Seal with Water-Lubricated Bearing for Ø25–40 mm Shafts

Name: Allpa TMF Axial Mechanical Propeller Shaft Seal with Water-Lubricated Bearing for Ø25–40 mm Shafts
SKU: ALP 9040125

SKU: ALP 9040125

ID 1416496

$ 565.87

1-2 weeks delivery time

Shaft Diameter:

Stern Tube Diameter:

Allpa TMF axial mechanical propeller shaft seal for inboard marine propulsion systems, featuring a stationary carbon flange, rotating stainless steel sealing ring, flexible rubber bellows and integrated water-lubricated neoprene bearing bush. Designed to accommodate axial and lateral shaft misalignment while reducing propeller shaft vibration. Available for Ø25, 30, 35 and 40 mm shafts with corresponding stern tube diameters of Ø40, 45, 50 and 55 mm. Uncompressed installation length A is 210 or 255 mm, with bellows pre-compression of approximately 20 mm and installed dimension B of 190 or 235 mm, depending on model. Requires initial adjustment and is designed for maintenance-free operation.

Description
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Allpa TMF Axial Mechanical Propeller Shaft Seal with Water-Lubricated Bearing for Ø25–40 mm Shafts

The Allpa TMF Axial Mechanical Propeller Shaft Seal is a mechanical face sealing assembly designed for inboard marine propulsion systems. The seal combines a stationary carbon flange, a rotating stainless steel ring, a flexible rubber bellows and an integrated water-lubricated neoprene bearing bush.

The carbon flange is connected to the stern tube through the rubber bellows. Pre-compression of the bellows presses the carbon flange against the stainless steel sealing ring, forming a mechanical face seal designed to prevent water leakage into the vessel.

The system accommodates axial and lateral shaft alignment differences while the water-lubricated neoprene bearing bush helps reduce propeller shaft vibration. Four configurations are available for 25, 30, 35 and 40 mm propeller shafts.

Key Features

Axial mechanical face seal: Sealing contact between a stationary carbon flange and a rotating stainless steel ring.
Flexible rubber bellows: Provides the pre-compression required to maintain contact between the sealing faces.
Integrated neoprene bearing bush: Water-lubricated component designed to support contact between bearing surfaces and reduce shaft vibration.
Axial and lateral compensation: Accommodates alignment differences within the propeller shaft installation.
Initial adjustment: The sealing assembly requires adjustment during installation.
Maintenance-free design: Designed for operation without routine adjustment after correct installation.
Inboard application: Intended for marine propeller shaft sealing systems.
Four available sizes: Compatible with Ø25–40 mm shafts and Ø40–55 mm stern tubes.

Technical Specifications

Parameter	Specification
Brand	Allpa
Series	TMF Axial
Product Type	Mechanical Propeller Shaft Seal
Application	Inboard Marine Propulsion Systems
Sealing Principle	Mechanical Face Seal
Stationary Sealing Component	Carbon Flange
Rotating Sealing Component	Stainless Steel Ring
Bellows Material	Rubber
Integrated Bearing	Water-Lubricated Neoprene Bearing Bush
Alignment Compensation	Axial and Lateral
Propeller Shaft Diameter (D)	Ø25, Ø30, Ø35 or Ø40 mm
Stern Tube Diameter (E)	Ø40, Ø45, Ø50 or Ø55 mm
Dimension A	210 or 255 mm, Depending on Model
Dimension B	190 or 235 mm, Depending on Model
Bellows Pre-Compression	20 mm, with Indicated Adjustment Tolerance of 0–5 mm
Maintenance	Initial Adjustment Required; Maintenance-Free Design
Available Configurations	4

Available Models and Dimensions

Article Number	Shaft Ø (D)	Stern Tube Ø (E)	Dimension A	Dimension B*
9040125	25 mm	40 mm	210 mm	190 mm
9040130	30 mm	45 mm	210 mm	190 mm
9040135	35 mm	50 mm	255 mm	235 mm
9040140	40 mm	55 mm	255 mm	235 mm

* Dimension B: B = A - 20 mm, with the indicated 0–5 mm adjustment tolerance for bellows pre-compression.

Mechanical Face Sealing System

The TMF Axial seal prevents water ingress through the interaction of two sealing components: a stationary carbon flange and a rotating stainless steel ring.

The carbon flange is connected to the stern tube through a flexible rubber bellows. The pre-compression of the bellows pushes the carbon flange against the rotating stainless steel ring, maintaining contact between the sealing faces.

This arrangement creates a mechanical sealing interface around the rotating propeller shaft.

Integrated Water-Lubricated Neoprene Bearing

A water-lubricated neoprene bearing bush is integrated into the rubber bellows assembly.

The bearing bush maintains contact between the bearing surfaces and contributes to reducing propeller shaft vibration during operation.

Axial and Lateral Alignment Compensation

The flexible sealing arrangement is designed to accommodate axial and lateral alignment differences in the propeller shaft installation.

Bellows flexibility allows the stationary carbon flange to maintain contact with the rotating sealing ring as the shaft moves within the intended operating arrangement.

Bellows Pre-Compression and Installation Dimensions

The TMF Axial shaft seal requires initial adjustment during installation. The specified installed length is determined by the uncompressed dimension A and the required bellows pre-compression.

The dimensional relationship is:

Dimension A: 210 mm for 25 and 30 mm shaft models; 255 mm for 35 and 40 mm shaft models.
Dimension B: 190 mm for 25 and 30 mm shaft models; 235 mm for 35 and 40 mm shaft models.
Bellows Pre-Compression: Approximately 20 mm, with an indicated adjustment tolerance of 0–5 mm.
Dimension D: Propeller shaft diameter.
Dimension E: Stern tube diameter.

Selection and Compatibility

Select the correct TMF Axial mechanical shaft seal according to both the propeller shaft diameter and the stern tube diameter.

9040125: Ø25 mm shaft / Ø40 mm stern tube.
9040130: Ø30 mm shaft / Ø45 mm stern tube.
9040135: Ø35 mm shaft / Ø50 mm stern tube.
9040140: Ø40 mm shaft / Ø55 mm stern tube.

Before ordering and installation, verify the shaft diameter, stern tube diameter, available installation length and required bellows pre-compression.