卡特彼勒高壓共軌C6.4

1、C6.4 ENGINE OVER VIEW 高壓共軌系統(tǒng)被世界內(nèi)燃機(jī)行業(yè)公認(rèn)為20 世紀(jì)三大突破之一, 將成為21世紀(jì)柴油機(jī)燃油系統(tǒng)的主流。 C6.4 ENGINE OVER VIEW What is a C6.4? C : Current nomenclature for CAT branded engines 6.4 : Engine displacement in Liters 1.06 Liter per Cylinder, 6 cylinder Inline Bore : 102 mm, Stroke : 130 mm Piston Displacement : 6.373 lite

2、r Rated Power : 110 117 kW (148-157 hP) 1800 rpm Compression ratio : 17.7 Turbocharged - ATAAC Replaces the 3066 mechanical engine C6.4 ENGINE OVER VIEW 高壓共軌系統(tǒng)利用較大容積的共軌腔將油泵輸出的高壓燃油蓄積 起來，并消除燃油中的 壓力波動，然后再輸送給每個噴油器，通 過控制噴油器上的電磁閥實現(xiàn)噴射的開始和終止。 其主要特點可以概括如下： 共軌腔內(nèi)的高壓直接用于噴射，可以省去噴油器內(nèi)的增壓機(jī)構(gòu)； 而且共軌腔內(nèi)是持續(xù)高壓，高壓油泵所需的驅(qū)動力矩

3、比傳統(tǒng)油泵 小得多。 通過高壓油泵上的壓力調(diào)節(jié)電磁閥，可以根據(jù)發(fā)動機(jī)負(fù)荷狀況以 及經(jīng)濟(jì)性和排放性的要求對共軌 腔內(nèi)的油壓進(jìn)行靈活調(diào)節(jié)，尤其 優(yōu)化了發(fā)動機(jī)的低速性能。 通過噴油器上的電磁閥控制噴射定時，噴射油量以及噴射速率， 還可以靈活調(diào)節(jié)不同工 況下預(yù)噴射和后噴射的噴射油量以及與主 噴射的間隔。 C6.4 ENGINE OVER VIEW 高壓共軌系統(tǒng)由五個部分組成，即高壓油泵、共軌腔及高壓油管、噴油器、電控單元、 各類傳感器和執(zhí)行器。供油泵從油箱將燃油泵入高壓油泵的進(jìn)油口，由發(fā)動機(jī)驅(qū)動的高壓油 泵將燃 增壓后送入共軌腔內(nèi)，再由電磁閥控制各缸噴油器在相應(yīng)時刻噴油。 C6.4 ENGINE OV

4、ER VIEW Overhead view of C6.4 engine cylinder head with rocker cover removed Integrated Cylinder head 4 valves Centrally located Injectors C6.4 ENGINE OVER VIEW Designed with most major service points located on the right side of the engine. Fuel Injection pump (1), Secondary Fuel Filter (2), Fuel p

5、riming pp (3), Oil fill cap (4), Dip stick (5),Engine breather (6), ECM (7) C6.4 ENGINE OVER VIEW 1.Air Inlet heater 2.Inlet heater relay C6.4 ENGINE OVER VIEW System capacity : 30 ltr Including filter Oil pump delivery : 66 L / min 1800 rpm C6.4 ENGINE OVER VIEW Water pump centrifugal type - Belt d

6、riven together with alternator Sealed bearing- no greasing required Coolant capacity (engine water jacket 9 L) Total : approx. 25 ltr Thermostat - Opens at 71 deg C 10 mm lift at 85 deg C C6.4 ENGINE OVER VIEW C6.4 Fuel System Caterpillar designed and Developed High Fuel Injection pressures Fully El

7、ectronically controlled Multiple Injection- reduce NOx and PM C6.4 ENGINE OVER VIEW Fuel system Overview Fuel system using common rail technology High pressure pump up to 160 MPA Hardened Fuel lines External fuel manifold C6.4 ENGINE OVER VIEW Fuel Manifold High quality steel component Designed to w

8、ithstand 23,000 psi Relief Valve Replace Lines if fitting is loosened Pump Pressurizes Fuel Transfer pump is serviceable C6.4 ENGINE OVER VIEW Low pressure fuel 43-58PSI 16000 PSI C6.4 ENGINE OVER VIEW LOW pressure fuel system Low pressure fuel circuit system pressure : 43-58 psi 300 - 400 kPA) Low

9、pressure fuel utilized to cool engine ECM Consists of Primary fuel filter / water separator (10 micron) Secondary Fuel filter (2 micron) Tertiary fuel filter (2 micron) in series 321 C6.4 ENGINE OVER VIEW Driven by High Pressure Pump Draws Fuel through Primary Filter Output Pressure 300 to 400 kPa 4

10、3 to 58 PSI Transfer Pump Primed by Priming Pump Hand or Electric No Lift Pump Required Transfer Pump C6.4 ENGINE OVER VIEW High pressure circuit Components High pressure Fuel Injection pump Fuel Manifold High pressure fuel lines Normal fuel rail pressure : 11000- 16000 psi HIGH PR PP CRM INJECTORS

11、C6.4 ENGINE OVER VIEW Fuel Pump Function Pump Raises Pressure ECM tells Injector to Fire Rail Pressure Drops ECM Detects Pressure Drop Sensed by Fuel Rail Pressure Sensor ECM tells Pump Solenoid to Increase Volume Also tells Pump Solenoid to Spill fuel once pressure is reached Do it Again! C6.4 ENGI

12、NE OVER VIEW Transfer pump Gear type High pressure pump Speed timing sensor Fuel pump solenoid- control injection pump output pressure to common rail Injection pump Solenoid is not serviceable Transfer pump and the secondary speed/timing sensor are the only serviceable components C6.4 ENGINE OVER VI

13、EW C6.4 ENGINE OVER VIEW High Pressure Relief Valve Fuel Pressure Relief Valve Protects System from Over-Pressure Opens at Constant Pressure of 160 MPa (23,000 PSI) Withstands Spikes to 190 Mpa (27,500 PSI) Returns fuel to Tank The primary function of the fuel pressure sensor is to constantly monito

14、r rail pressure. The high pressure relief valve protects the high pressure fuel system from excessive pressures. C6.4 ENGINE OVER VIEW Each Injector has a solenoid. The solenoid receives current from ECM & actuates the Injector. When no Injection : No current to solenoid- control valve closed -fuel

15、from the rail stops at the injector control valve Injection : Solenoid is energized- armature plate moves up- valve is opened- High pr fuel flows to nozzle area Injection begins (no of orifice : 6 ) When the current to solenoid is stopped, armature plate pushed down- valve seat is closed . Any remai

16、ning high pressure fuel exits through drain port C6.4 ENGINE OVER VIEW To nozzle Solenoid energized Valve Injector Function ECM Energizes Injector Valve Lifts Fuel Flows to Nozzle Solenoid de- energized Injector De-energizes Valve Closes Unused fuel flows back to Transfer Pump via passage in the Hea

17、d C6.4 ENGINE OVER VIEW When replacing injector, replace all of the following 1.O ring 2.Washer copper Injector pipe Rubber boot that seals valve cover opening Note : When removing a pipe and reusing an Injector, Always cap the injector Immediately until ready to install. Do not over tighten the sol

18、enoid connection terminals. C6.4 ENGINE OVER VIEW Fuel Injector Trim code Do Write down the Injector Serial Number and Confirmation Code before you install the Injector Do use Cat ET to Program ECM with proper Injector Trim File Do Look for the Trim File CD in the Injector Box Trim file can be found

19、 in sis web C6.4 ENGINE OVER VIEW Primary and secondary speed/timing sensor are of same part number C6.4 ENGINE OVER VIEW Fuel Injection Serviceability NEVER loosen high pressure pipes when engine is running! 23,000 PSI Use Electronic Service Tool to Troubleshoot Injector Problems Injectors have no

20、serviceable parts. Pump Solenoid is non serviceable. If the solenoid is removed the whole pump assembly must be replaced. Transfer pump is a serviceable item, separate from High Pressure pump. Speed sensor is serviceable. C6.4 ENGINE OVER VIEW GENEARAL SERVICE PROCEDURES w Common rail fuel technolog

21、y requires a high degree of cleanliness. w Before attempting any work on the fuel system ensure that the engine is cleaned of any dirt that might contaminate the fuel system. w Parts must be inspected prior to use to ensure capping is intact and parts are clean and undamaged. w Any fuel system compo

22、nents that are removed or exposed should be capped with new, clean caps to prevent dirt ingress w Use anti contamination kit part No 278-4138 C6.4 ENGINE OVER VIEW GENEARAL SERVICE PROCEDURES CONT w Do not pre fill the filters. Install filter dry and use priming to fill with fuel w Common rail fuel

23、system is a self bleeding fuel system and does not require air to be purged from the system. w Once a fitting has been loosened, the entire fuel pipe must be replaced with a new part to ensure proper seating and leak-free performance. Due to the unique “internally hardened” manufacturing process, hi

24、gh pressure pipes are single use w Common rail fuel systems operate at extremely high pressures (20000 psi). Never loosen or open a high pressure fuel line while cranking or running a common rail fuel system. C6.4 ENGINE OVER VIEW GENEARAL SERVICE PROCEDURES CONT w FUEL tank drain : Drain water and

25、sediments from Fuel tank daily, Keep fuel tank breather filter clean. w Ensure, once the engine is shut down, fuel rail pressure is reduced to zero, before any repair. If a leak is suspected, do not check / repair the fittings unless the engine is OFF and pressure is neutralized. C6.4 ENGINE OVER VIEW ENGINE MAINTENANCE INTERVALS w Engine Oil SOS250 Hours w Coolant SOS250 Hours w Oil and Filter Change500 Hours (SOS to determine this) w Fuel Filter 500 Hours w Engine valve lashFirs