Description: Time period, starting from the first use and ending with the time when the limit state is reached.; Name: Service life
Description: Time interval from first use until the instant when a limiting state is reached ; Name: useful life
Description: average speed given by the stroke length multiplied with the number of complete pumping cycles of the piston, plunger or piston attached to the diaphragm per minute (stroke per minute or pump crank speed); Name: piston velocity