An improved hot water pressure washer utilizes a combination of technologies to achieve lower emission levels and increased operational efficiency. A forced air natural gas or forced air oil burner utilizes a flue gas and recirculation line to lower carbon monoxide and NOx emissions from a burner. A flue gas heat exchanger is utilized to lower the temperature of the exhaust gas. The lower exhaust gas temperatures allow for lower cost materials to be utilized. The efficiency levels of a hot water pressure washer are increased over known devices.

The invention is a vapourising device (10) for vapourising a volatile liquid for supply to an environment. The device has a housing 100 having an inlet (109) for receiving inlet air which is warmed by inlet heater (111) before being supplied to cartridge assembly (200). Cartridge assembly (200) has a reservoir (204) for containing the liquid to be vapourised and at least one wick (206), one end of which is located in the reservoir to receive and transport the liquid to the other, exposed end of the wick where the liquid evaporates and mixes with the supplied stream of heated inlet air. The wick may be heated by a wick heater (211). The device also includes an outlet duct section (217) between the wick (206) and the outlet (221) which is conical in shape and is configured to accelerate the flow of the mixture of inlet air and vapourised liquid away from the wick towards the outlet (221). The invention provides increased control of the vapourisation process and helps to reduce condensation of the volatile liquid back onto the apparatus or onto surrounding surfaces.

A layered object manufacturing apparatus includes a nozzle that is provided with a body having an opening from which a laser beam is output and powder of a material is ejected.

A gas dynamic spray unit is provided that includes gun housing halves secured about a heater assembly. The heater assembly includes a one-piece, multi-passage ceramic heater core. The heater assembly is retained within the gun housing using locating features provided on the heater assembly and the gun housing. The heater assembly includes a heater housing at least partially surrounding the heater core. A biasing member biases the ceramic heater core toward a tapered outlet, which is provided by a deflecting cone surrounded by an insulating cone.

A thermal spraying system includes a fixing device and a thermal spraying apparatus that are relatively movable. The thermal spraying apparatus includes a hollow pipe, an extrusion die, a transporting device, a helical pipe, a fluid supplying device, and a heater. The hollow pipe defines an accommodating space. The extrusion die is connected with the hollow pipe. The extrusion die has a nozzle. The nozzle is in spatial communication with the accommodating space. The transporting device is used for moving a raw material to pass through the nozzle. The hollow pipe is surrounded by the helical pipe. An end of the helical pipe is connected to the nozzle. The fluid supplying device is connected to another end of the helical pipe. The heater encloses the helical pipe and the hollow pipe for heating the helical pipe and the accommodating space.

An apparatus and method for open-atmosphere flame based spraying employs a nozzle to preheat, pressurize and atomize a mechanically pumped reactive and flammable liquid solution through a small orifice or a nozzle and then a set of pilot flames to combust the spray. The liquid feedstock is preheated to a supercritical temperature before reaching the nozzle and is pressurized before spraying due to a reduced size of the outlet port of the feedstock flow channel relative to the inlet. A supplementary collimating, or sheathing, gas is supplied to the flow channel of the feedstock and both the feedstock and the supplementary gas are uniformly heated before spraying. This arrangement helps to avoid clogging of the nozzle and results in satisfactory control of the properties of the particulate products of the spraying procedure.

A layered object manufacturing apparatus includes a nozzle that is provided with a body having an opening from which a laser beam is output and powder of a material is ejected.