Max Straubel

THE ROBERT BOSCH IN-LINE INJECTION PUMP (TYPE "P") FOR DIESEL ENGINES--FURTHER DEVELOPMENT OF A PROVEN LINE OF INJECTION PUMPS

The Robert Bosch series of inline pumps serves engine output requirements ranging from 13 to 268 bhp per cylinder; in this family of injection pumps, the Type P inline pump is mainly applied to heavy-duty, direct injected truck engines, with power output up to 80 bhp per cylinder. Since 1962, approximately 1.5 million pumps of this type have been supplied to the field. Five aims of the new version of the P-pump are to: increase the permissible peak injection pressure into the 1200 bar range; increase the maximum quantity of fuel injected by enlarging the maximum plunger lift from 11 to 12 mm while maintaining a maximum plunger diameter of 13 mm; improve performance with virtually unchanged pump external dimensions so as not to complicate installation on the engine; utilize the existing transfer line during pump production to maintain a high degree of accuracy and keep costs down; and combine the wide range of add-on units to form a complete module with little or no overlapping. Individual stages in this development work are described, and research results are illustrated in a modular overview and test findings.