Propellers

Diverse Propellers provides an essential service for vessel owners, through its non-ferrous foundry and dedicated propeller machining capability. We manufacture two, three, four and five-bladed propellers ranging from 200 to 1800mm. We also produce propeller blades to suit variable control propellers with total diameters of up to 4 metres.

We offer a full service in propeller specification, advising on blade numbers and pitch to suit a vessel’s power unit and hull form and provide maintenance, repitch or repair of damaged propellers. Diverse Propellers’ workshops are equipped with dedicated machinery allowing computerised pitch checking and dynamic balancing, with variable length and a capacity of 1800mm and 400kg.

One of only two such foundries in New Zealand, Diverse’s non-ferrous foundry has the capability to bronze-cast complete propellers or individual blades of up to 1800mm diameter, with a weight of around 1.1 tons. The foundry also casts a range of fittings such as stern bearings, struts, stuffing boxes, propeller nuts vent cowlings and more and can provide cored bronze for industrial and general bushing needs.

Diverse Propellers has a very large pattern library – a selection of blade templates, some dating back to the inception of N&B Propellers, Diverse’s forerunner. For each propeller project, our shipwrights will create a blade template or ‘blank’ from wood - or adapt an existing one. This blank is then used to create a full mould of the required propeller for casting in our foundry. Most are cast in AB2, a nickel aluminium bronze widely used in marine applications, having high strength and good wear resistance. Once cast, propellers go through various stages of machining: Centre-boring to the required shaft taper; Machining of keyways; Grinding and polishing; pitch checking and adjustment, and dynamic balancing.