Integrated tappet assembly

A tappet assembly (100) used in mechanical equipment, comprising:

• a tappet body (108) including a lower carrier portion (152) having an opening (176) formed on a bottom surface (156) of the lower carrier portion (152), and an upper shell portion (158) having a cavity (150) defined by an inner wall (160) of the upper shell portion (158) and a top surface (154) of the lower carrier portion (152), the lower carrier portion (152) and the upper shell portion (158) being integrally formed as a single-piece unit;
• a roller (110) having a substantially cylindrical shape and a longitudinal length less than an outer diameter of the tappet body (108), the roller (110) configured to be inserted into the opening (176) of the lower carrier portion (152);
• and
• a ring (111) configured to restrict movement of the roller (110).