 | This articleneeds additional citations forverification. Please helpimprove this article byadding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Wärtsilä-Sulzer RTA96-C" – news ·newspapers ·books ·scholar ·JSTOR(September 2023) (Learn how and when to remove this message) |
| RT-flex96C | |
|---|---|
| Overview | |
| Manufacturer | Wärtsilä |
| Production | 2006–present |
| Layout | |
| Configuration | Two-strokestraight-14 |
| Cylinder bore | 96 cm (38 in) |
| Piston stroke | 2.50 m (98 in) |
| RPM range | |
| Max. engine speed | 120 |
| Combustion | |
| Turbocharger | Single |
| Fuel type | heavy fuel oil |
| Output | |
| Power output | 80,080 kW (107,390 hp) |
| Dimensions | |
| Length | 26.59 m (87.2 ft) |
| Height | 13.5 m (44 ft) |
| Dry weight | over 2,300 t (2,535short tons; 2,264long tons) |
TheWärtsilä RT-flex96C is atwo-stroketurbocharged low-speeddiesel engine designed by theFinnish manufacturerWärtsilä. It is designed for largecontainer ships that run onheavy fuel oil. Its largest14-cylinder version is 13.5 m (44 ft) high, 26.59 m (87.2 ft) long, weighs over 2,300 t (2,535short tons; 2,264long tons), and produces 80.08 MW (107,390 hp). It is the largestreciprocating engine in the world.
The 14-cylinder version first entered commercial service in September 2006 aboard theEmma Mærsk. The design is similar to the olderRTA96C engine, but withcommon rail technology (in place of traditionalcamshaft,chain gear,fuel pump andhydraulic actuator systems). This provides maximum performance at lowerrevolutions per minute (rpm), reduces fuel consumption and emits lower levels of harmful emissions.
The engine hascrossheadbearings so the always-verticalpiston rods create a tight seal under thepistons. Consequently, thelubrication of the engine is split: the cylinders and the crankcase use different lubricants, each being specialised for its designated role. The cylinders are lubricated by continuous timed injection of consumable lubricant, formulated to protect the cylinders from wear and to neutralise the acids formed during combustion of the high-sulfur fuels commonly used. The crosshead design reduces sideways forces on the piston, keeping diametral cylinder liner wear down to about 30 μm per 1,000 hours.[1]
As a piston descends, it compresses incoming combustion air for the adjacent cylinders. This also serves to cushion the piston as it approaches bottomdead centre, thereby removing some load from the bearings. The engine isuniflow-scavenged by way of exhaust valves that are operated by electronically controlled hydraulics, thus eliminating the camshaft.
As of 2006,[needs update] more than 300 RT-flex96C engines and older RTA96C engines were in service or on order.[2]
| Configuration | Turbochargedtwo-strokedieselstraight engine, 6 to 14cylinders |
| Bore | 960 mm (38 in) |
| Stroke | 2,500 mm (8.2 ft) |
| Displacement | 1,828.7litres (111,590 in3) percylinder |
| Engine speed | 15–102 RPM[3] |
| Mean effective pressure | 1.96 MPa (284 psi) @ full load, 1.37 MPa (199 psi) @ maximum efficiency (85% load) |
| Mean piston speed | 8.5 m/s (28 ft/s) |
| Brake specific fuel consumption | 171 g/(kW·h)[3][a] |
| Power | Up to 5,720 kW per cylinder, 34,320–80,080 kW (46,020–107,390 bhp) total |
| Torque | Up to 7,603,850 N⋅m (5,608,310 lbf⋅ft) @ 102 rpm |
| Specific power | 29.6–34.8 kW (39.7–46.7 bhp) pertonne, 2,300 tonnes for the 14-cylinder version |
| Mass of fuel injected per cylinder per cycle | ~160 g (5.6 oz) @ full load (Whole engine uses up to 250 tons of fuel per day.) |
| Crankshaft weight | 300 t (660,000 lb)[1] |
| Piston weight | 5.5 t (12,000 lb) |
| Piston height | 6 m (20 ft) |