Abstract: A method of monitoring the inner surfaces of copper-alloy condenser tubes of a condenser through which seawater flows as a coolant by controlling a ferrous-ion injecting operation to inject ferrous ions into the coolant for forming a protective film on the inner surfaces of the condenser tubes, and a sponge-ball cleaning operation to clean the inner tube surfaces by passing sponge balls through the condenser tubes. During an initial period of exposure of the condenser tubes to the coolant after installation of the condenser tubes in the condenser, the ferrous ions are injected into the coolant to form the protective film on the inner surfaces of the condenser tubes until the polarization resistance of the condenser tubes has reached 10.sup.4 .OMEGA.cm.sup.2. Subsequently, the ferrous-ion injecting operation and the sponge-ball cleaning operation are executed while the polarization resistance and heat transfer rate of the condenser tubes are monitored.

Abstract: A condenser including a plurality of condenser tubes through which a coolant is caused to flow, a device for injecting ferrous ions into the coolant before it passes through the condenser tubes to form a protective film on an inner surface of the condenser tubes, and a device for introducing sponge balls into the condenser tubes for cleaning their inner surfaces. The condenser has a by-pass line extending outside the body of the condenser, in parallel connection with the condenser tubes. The by-pass line has a monitor tube of the same material and size as the condenser tubes, so that the coolant flows through the monitor tube under the same conditions as the coolant flowing through the condenser tubes. The monitor tube is equipped with a device for measuring a polarization resistance of the monitor tube, and a device for sensing a fouling condition of the inner surface of the monitor tube.

Abstract: A coating method for coating the inner surface of a long tube of small diameter, specifically tubes for a condenser. The coating is a type of spray coating wherein a long flexible supply hose, longer than the long tube to be coated, is reciprocated in the long tube with a spray nozzle attached to the tip thereof for spraying the paint by the action of compressed air, from one end of the long tube to the other end thereof while spraying the paint in atomization. The long flexible supply hose of double structure or sometimes of triple structure is composed of a short heating pipe portion adjacent to the spray nozzle and a long flexible hose portion. The paint and compressed air supplied through separate passages in the supply hose are heated to a predetermined temperature by heating means, for example, a sheathed electrical heater wound about an inside pipe of the heating pipe portion upstream of where the paint is sprayed.

Abstract: A coating method and apparatus for coating the inner surface of a long tube of small diameter, specifically tubes for a condenser. The coating is a type of spray coating wherein a long flexible supply hose, longer than the long tube to be coated, is reciprocated in the long tube with a spray nozzle attached to the tip thereof for spraying the paint by the action of compressed air, from one end of the long tube to the other end thereof while spraying the paint in atomization. The long flexible supply hose of double structure or sometimes of triple structure is composed of a short heating pipe portion adjacent to the spray nozzle and a long flexible hose portion. The paint and compressed air supplied through separate passages in the supply hose are heated to a predetermined temperature by heating means, for example, a sheathed electrical heater wound about an inside pipe of the heating pipe portion upstream of where the paint is sprayed.

Abstract: A method and apparatus for coating a long tube of small diameter by means of inserting a supplying hose of double structure, with a spray nozzle ahead and two separately extending inner and outer hoses for supplying paint and compressed air respectively therethrough, into the long tube from one end opening thereof toward the other end opening thereof, and retracting the spray nozzle, when it has reached the destination, while spraying the paint at a predetermined speed. The inner hose for the paint is made of flexible material as an elastic hose for being compressive in the diametrical direction under the pressure from the compressed air in the outer hose and again restorable to the original shape when the pressure is released.