Diesel
                 in-line fuel-injection pumps
                   Mobility in this day and age is not          Combustion in the diesel engine
                   least of all a question of common            The diesel engine                         2
                   sense and economy.                           Diesel fuel-injection systems: 
                   In future, the technology without            An overview
                   which these considerations regard-           Fields of application                     4
                   ing individual mobility are meaning-         Technical requirements                    4
                   less will continue to be of decisive         Injection-pump designs                    6
                   importance.
                   In the automotive sector, economi-           PE in-line fuel-injection pumps
                   cal and quiet-running diesel engines         Fuel-injection systems                    8
                   are making history.                          Fuel-injection techniques                 9
                   Bosch in-line and distributor injec-         PE standard in-line fuel-injection 
                   tion pumps have played, and                  pumps                                    16
                   continue to play, a major role in            PE in-line fuel-injection pumps 
                   these developments. The introduc-            for alternative fuels                    26
                   tion of electronic controls (Electronic      PE in-line control-sleeve 
                   Diesel Control/EDC), together with           fuel-injection pumps                     27
                   increased injection pressures and            Fuel supply and delivery                 30
                   even more precise fuel metering,             Operation of the in-line 
                   has made it possible to further in-          fuel-injection pump                      36
                   crease the diesel engine’s service           Nozzles and nozzle holders               40
                   life, as well as reducing its exhaust-
                   gas emissions, while at the same             Single-plunger fuel-injection pumps
                   time even further improving its fuel-        PF single-plunger 
                   economy figures.                             fuel-injection pumps                     48
                   In this “Technical Instruction” man-         PF-MV solenoid-valve-controlled 
                   ual, from the Diesel Fuel Injection          single-plunger fuel-injection pumps      52
                   series, you have access to a wealth          Innovative fuel-injection systems        54
                   of information on a variety of diffe-
                   rent fuel-injection pumps, as well as        Start-assist systems                     56
                   on important components and their
                   functioning. These components in-
                   clude for instance, the delivery-
                   valve assemblies and the plunger-
                   and-barrel assemblies.
                   The appropriate governors for the
                   PE in-line injection pumps are dealt
                   with in the Technical Instruction
                   manual “Governors for Diesel In-
                   Line Fuel-Injection Pumps”.
                In-line    PE standard in-line                           – A number of high-pressure fuel-in-
         fuel-injection                                                     jection lines, corresponding to the
               pumps       fuel-injection pumps                             number of engine cylinders, connec-
                                                                            ting the injection pump and the injec-
                                                                            tion nozzles,
                           Design and construction                       – The injection nozzles.
                           The standard PE in-line injection pumps       The injection pump’s camshaft is driven
                           incorporate their own camshaft, and a         by the diesel engine. Injection-pump
                           plunger-and-barrel assembly (pumping          speed and crankshaft speed are identical
                           element) for each engine cylinder for 2-stroke engines. For 4-stroke engi-
                           (Fig. 1).                                     nes, pump speed is the same as engine
                                                                         camshaft speed, in other words half
                           The complete fuel-injection system is         crankshaft speed.
                           comprised of:                                 The drive between injection pump and
                           – A fuel-injection pump,                      engine must be as torsionally rigid as
                           – A mechanical (flyweight) or electronic      possible if today’s high injection pres-
                              governor for control of engine-speed       sures are to be generated.
                              and injected fuel quantity,                There are a number of different sizes of
                           – A timing device (if required) for varying   in-line injection pumps for the various en-
                              the start of delivery as a function of     gine outputs.
                              engine speed,                              The injected fuel quantity depends upon
                           – A fuel-supply pump for delivering the       the swept volume of the injection-pump
                              fuel from the fuel tank, through the fuel  barrel, and maximum (pump-side) injec-
                              filter and the fuel line, to the injection tion pressures are between 400 and
                              pump,                                      1,150 bar.
                           Fig. 1
                            PES in-line fuel-injection pump
                            1 Delivery-valve holder, 2 Filler piece, 3 Delivery-valve spring, 4 Pump barrel, 5 Delivery valve, 6 Inlet
                            port and spill port, 7 Control helix, 8 Pump plunger, 9 Control sleeve, 10 Plunger control arm, 11 Plunger
                            return spring, 12 Spring seat, 13 Roller tappet, 14 Cam, 15 Control rack.
                                      1
                                      2
                                      3
                                      4
                                      5
                                      6
                                      7
                                      8                                                                  15
                                      9
                                     10
                                     11
                                     12
                                     13
                   16                                                14                                            UMK0409Y
                 To lubricate the moving injection-pump        A, M, MW, and P are manufactured in            Standard
                 components (e.g. camshaft, roller tap-        large batches (Fig. 2).                        in-line
                 pets etc.) there must be a certain amount     The pump sizes ZW, P9, and P10 are             fuel-
                 of oil in the injection pump. The injection   available for even higher cylinder power       injection
                 pump is connected to the diesel engine’s      outputs.                                       pumps
                 lube-oil circuit, and oil circulates through
                 the pump during operation.                    Method of operation
                 Each pump type is allocated to a given
                 type series, which in some cases overlap      Interaction between the components
                 with respect to their power ranges. These     The camshaft of the PE in-line injection
                 will be described in the following chap-      pump is integrated in the aluminum pump
                 ters.                                         housing. It is connected to the diesel en-
                 Two different construction principles are     gine either through a timing device,
                 used for in-line injection pumps: The prin-   through a coupling element, or directly. A
                 ciple for the M and A pumps, and that for     roller tapper with spring seat is located
                 the MW and P pumps.                           above each camshaft cam. The spring
                 The power outputs of diesel engines           seat provides a positive-drive connection
                 equipped with in-line injection pumps         between pump plunger and roller tappet.
                 range from 10 to 70 kW per cylinder. This     The pump plunger moves up and down in
                 broad power-output range is made possi-       the pump barrel, and together these two
                 ble by the availability of a wide variety of  components form the plunger-and-barrel
                 different pump versions. The pump sizes       assembly (pumping assembly).
                 Tab. 1
                 Overview
                 Features                 PE in-line injection pumps
                                          M           A           MW          P1...3000   P7100...8000
                 Injection pressure       550         750         1100        950         1300
                 in bar (pump side)
                 Application              Passenger  Light to medium                      Heavy
                                          cars        commercial vehicles,                commercial
                                          and         tractors,                           vehicles, indus-
                                          vans        industrial engines.                 trial engines.
                 Output per cylinder      20          27          36          60          160
                 in kW/cylinder
                 Fig. 2
                  In-line injection pumps. Size comparison (looking onto camshaft end)
                         M                 A                MW             P1…3000         P7100…8000
                                                                                                         UMK0803Y17