Abstract:
The method comprises steps for delivering lubricating oil under pressure from a lubricating oil reservoir (7) via a forced lubrication system to injectors (3) provided in the cylinder walls. A number of injectors (3) are used, each adapted for injecting a dosed amount of lubricating oil into each cylinder. The method further includes steps of: - establishing data indicating the temperature of cylinder linings (5); - establishing data that indicate the temperature of the lubricating oil in the lubricating oil reservoir (7); - storing the temperature data for cylinder linings (5) and the lubricating oil in a computer; - establishing at least one temperature regulating unit (9) controlled by the computer and connected with the delivered lubricating oil for establishing a temperature regulation of the lubricating oil before injection into the cylinder; - controlling the temperature regulation of the lubricating oil in dependence of the temperature of the cylinder linings (5) and the temperature of the lubricating oil in the lubricating oil reservoir (7), as the computer controls heating/cooling in the temperature regulating unit (9) for influencing the viscosity of the lubricating oil such that a uniform injection independent of the temperature of the cylinder linings (5) is established.
Abstract:
An improvement for lubrication in slow-running two-stroke engine, especially marine diesel engines, is achieved in lubrication using Swirl Injection Principle (SIP) by lo- cating the lubricant injectors (4) closer to the TDC than 1/5 of the full stroke of the piston (32), which is closer than in typical marine diesel engines. This can be achieved by reconstructing cylinder liners (2) or by adding new mounting holes to the cylinder (3). In case that such reconstruction is not possible, an improvement of SIP principles can also be achieved by directing the spray towards the TDC or to a location on the cylinder liner (2) closer to the TDC as compared to the location of the SIP valves, for example under an angle of more than 30 degrees or even more than 60 degrees when measured from a plane normal to the cylinder axis. The two improvements can be combined.
Abstract:
There is disclosed a hydraulic system for cylinder lubrication of engine cylinders in large diesel engines, in particular marine engines, by injection of oil. The system is designed with injectors (13) and a lubricating apparatus (11) which includes a number of pump units (8). Each pump unit (8) is connected with an associated injector (13) via a connecting pipe (12). In the connecting pipe (12), between a pump unit and an associated system unit a leak detector (10) is provided, adapted for emitting a signal when the oil pressure in the connecting pipe (12) go under a predetermined level. Hereby is achieved a reliable, technically simple and cheap system for leak monitoring which enables continuous monitoring of leakage with running engine so as to ascertain if one or more injectors (13) are leaking.
Abstract:
There is disclosed a valve arrangement (1) for dosing a fluid via a dosing unit (2). It includes two valves(V1, V2) with a first and a second valve element (6, 7) for opening and closing ports (A-F) in the valves. The valve arrangement (1) is connected via its ports (C, E, F) with a feed line (3) and a return line (4) connecting the valve arrangement (1) with a pressure source (5) for the fluid. In order to achieve a precise dosing of small amounts of fluid, the valve arrangement is made with a first and a second three-way valve (V1, V2). The first valve (V1) has a first port (A) connected with a first port (D) in the second valve (V2), a second port (B) connected with a connecting line (8) to the dosing unit (2), and a third port (C) connected with the feed or return line (3, 4).The second valve (V2) includes a second port (E) and a third port (F) connected with the feed line (3) or the return line (4). The first valve element (6) has a first position in which the second and third ports (B, C) communicate, and a second position where the first and second ports (A, B) communicate, and the second valve element (7) has a first position in which the first and third ports (D, F) communicate, and a second position where the first and second ports (D, E) communicate.
Abstract:
There is disclosed a method for cylinder lubrication of large diesel engines, such as marine engines. Injection of lubricating oil is performed via a number of injection units that correspond to a multiple of the cylinder number in the engine. There is desired an efficient distribution of the lubricating oil, not only across the periphery of the cylinder, but also across the travel of the piston in the cylinder in order thereby to reduce the consumption of lubricating oil. This is achieved in that lubricating oil is supplied by a combination of injection of a first part of the lubricating oil directly on a ring area of the cylinder wall before the passage of the piston and an injection of a second part of the lubricating oil directly onto the piston during its passage.
Abstract:
There is described a hydraulic lubricating apparatus and a hydraulic piston for a dosing system for cylinder lubrication oil, e.g. in marine engines. The lubricating apparatus includes at least on hydraulic piston (106) which may be pressurised by hydraulic oil, a number of dosing pistons (21) and a distributor plate (7) which at one side of it is in contact with the dosing pistons (21) and which at its other side is in contact with the at least one hydraulic piston (106) for displacing the distributor plate for actuating the dosing pistons. The hydraulic piston (106) is provided with an inner boring (B) extending in the direction of displacement of the hydraulic piston, the boring being provided with an insert (C5E) including an insert cylinder (C) in which is provided a hollow insert piston (E) in contact with a supply opening (H) for hydraulic oil. Hereby is achieved that the hydraulic piston (106) can be moved faster such that improved pressure and flow conditions and thus substantially enhanced pressure and flow in the atomising nozzles may be attained, and consequently improved performance of the lubricating system.
Abstract:
There is described a centralised lubrication system and a method for lubricating the cylinder faces in large diesel engines, in particular marine engines. The system includes at least one lubricating apparatus (2) having a rotating control shaft (18) for preferably running synchronously with the main shaft (44) of the diesel engine. In order to make a system that does not have a mechanical drive between the lubricating apparatus (2) and the main shaft (44), the system is constructed with an AC motor (36) driving the control shaft (18). Reference means (72, 78) are provided in association with the main shaft (44), indicating the angular position of the main shaft, and sensor means (74, 76, 80) detecting the position of the reference means. Furthermore, the system includes a control unit (40) receiving signals from the sensor means and which includes means for detecting angular position as well as angular speed of the reference means and thereby of the main shaft (44). The control unit (40) is connected with and controls the AC motor (36) for regulating the rotation of the control shaft (18) and thereby actuation of reciprocating pumps providing the cylinder lubrication.