Hydraulic machinery is used across the entire plastic industry. Controlling the volume of molten plastic going into the mold cavity can be tricky. With proper hydraulic machinery this process can be monitored through computer programs. The pressure, temperature, and amount of plastic can be accurately controlled. The molds themselves are often times moved through the use of hydraulics. The pressure that secures and maintains the seal of mold halves is also usually controlled via hydraulic machinery. Outside of the actual molding machinery forklifts and loading or packaging machinery also contain hydraulic mechanisms.