Boiler for generating steam and comprising a furnace wall defining a furnace, a casing wall concentrically encircling the furnace wall and jointly with the furnace wall defining a substantially annular interspace, steam consucting tubes positioned at the furnace wall and the casing wall and being in connection with top and bottom annular vessels and a flue gas aperture in the furnace wall for establishment of connection from the furnace to the annular interspace. At least one of the two walls, i...

A marine propeller with increased performance in reverse has a hub and a multiplicity of blades extending radially outward. A portion of the trailing edges of some or all of the blades are modified to lessen interference between blades and increase the bite of those blades when operated in reverse.

A marine riser has couplings with screw-threads for securing marine riser sections together, and a carousel mechanism for coupling auxiliary lines to the marine riser sections at various locations along the sections to permit the lines to rotate freely relative to the marine riser sections as the sections are rotatably assembled. The marine riser also has a buoyancy module which houses choke and kill lines in buoyancy module fairing portions.

A two-cycle, multi-cylinder engine maintains roughly equal temperatures between cylinders, despite differing exhaust efficiencies between the cylinders. Several ways of reducing the temperature of one of the cylinders in comparison to the other are disclosed. One embodiment involves supplying more coolant to the cooling passages around the hotter running cylinder. Other ways involve reducing the compression ratio or retarding ignition timing in the hotter running cylinder in comparison to the ot...

A marine ladder includes a catch mechanism in which a catch tyne is directly secured to the marine ladder without the need for additional structural members or support. The catch tyne is formed as a substantially L-shaped member that dependingly connects to a transverse bar on the dock-anchored frame of the ladder and defines a channel for receiving a leg of a user-selected one of the un-shaped rungs on an elongated ladder portion. The ladder portion is slidably engageable with and along the anc...

An engine for a watercraft includes a cooling system having a coolant supply. The coolant supply supplies an engine coolant jacket with a flow of coolant that is controlled by a temperature dependent flow control valve. The coolant supply also supplies an exhaust conduit coolant jacket independently of the engine coolant jacket.

A muffler comprises a housing having an exhaust inlet and an exhaust outlet. A first exhaust chamber is disposed concentrically within the housing and is connected with the exhaust inlet. The first exhaust chamber includes a plurality of openings through a first exhaust chamber wall for distributing exhaust gas radially outwardly therethrough. A second exhaust chamber is disposed concentrically around the first exhaust chamber and receives exhaust gas passed to it from the first exhaust chamber....

A marine anchor having a shank connectible to an anchor rode at one end and having a double ploughshare fluke rigidly mounted at the other end thereof is described. The fluke consists of two symmetrically mounted part-cylindrical blades disposed on each side of a central ridge in the medial plane of the shank and extending from a forward apex to divergent trailing ends. A ballast weight is mounted under the convex surfaces of the blades and contained within the tangential plane to the convex sur...

A compressor having a corrosive resistant coating is disclosed. The coating has a first spray coated metallic layer. A sealant layer is disposed over the sprayed metallic coating which has an organic component, a solvent component, and an inorganic phase.

A marine fender for securely affixing to an object such as a dock, piling, seawall, and the like is formed by extrusion of a resilient material. It is provided with unique energy absorbing properties. The fender has a uniform cross section with an outer arcuate wall, and an inner arcuate wall. Strips connect the two walls to transmit forces from items impinging on the outer wall to the smaller arch of the inner wall. A planar panel connects the two walls and transmits any remaining forces to the...