... , Maximum working pressure are 35Mpa, the pressure of charging is 3~5Mpa,there is no air pressure when pump leave the factory ... the pressure.2. The gear wheel uses the Herringbone Gears.3.The main technical parameters of F-1300 mud pump.4 ... working more than 5 years when in a ggeneral conditions.3. Three times QC process, we can ensure 100% are work ...