Read existing propeller markings and gather the drawings, dimensions and vessel details needed for a replacement enquiry.
Photograph the markings before choosing a size
For an existing installation, start with the propeller identification, shaft drawing and previous supply records. Send close-up photographs of any stamped or cast markings, together with an overall photograph.
A marking such as 14 × 19 describes a 14-inch diameter and 19-inch pitch. This is an example of how to read a size, rather than a recommended size for a particular vessel. Pitch describes theoretical forward travel per revolution; diameter describes the circle swept by the blade tips.
Record the blade count, rotation, material, maker and part number where known. For a twin-screw vessel, label port and starboard separately. If the rotation marking is missing, send the drawing or manufacturer reference so that the required direction can be confirmed consistently.
The shaft and hub fit matter too
A diameter and pitch alone do not describe the complete replacement. A dimensioned drawing or an agreed sample inspection gives a much clearer picture of the propeller-to-shaft and shaft-to-coupling connections.
Useful details for matching an existing assembly
Component
Details to provide
Propeller hub
Bore and taper details, hub length, keyway and retaining arrangement, with the existing drawing if available.
Shaft
Diameter, overall length, material specification and dimensions of each machined end.
Propeller end
Taper length and end diameters, keyway dimensions, thread specification and nut details.
Coupling end
Coupling make/model, bore or taper, keyway, flange dimensions and bolt pattern where applicable.
Associated parts
Bearing and seal references, shaft-contact dimensions and any items being renewed at the same time.
Separate a replacement from a change in performance
Tell us whether you are replacing the existing specification, repairing damage or reviewing performance after a change. Include any previous repair or repitching records: the current propeller may differ from the original supply specification.
When reviewing the specification, provide engine power and rated RPM, gearbox reduction ratio, vessel type and displacement, waterline length, normal operating load and speed. Include recorded full-throttle RPM under normal load if available. VETUS identifies these vessel and machinery details as inputs to propeller selection.
Propeller and shaft dimensions vary with the installation. For Singapore harbourcraft enquiries, the most useful starting point is your vessel’s actual equipment and duty, followed by confirmation of the proposed specification.
FOR YOUR QUOTATION
Send a propulsion enquiry
Vessel, engine and gearbox details
Propeller markings, blade count and rotation reference
Shaft drawing, measured dimensions or sample availability
Replacement, repair or performance-review requirement