what is a graduated cylinder made out of
Graduated cylinder Large graduated cylinders are usually made up of polypropylene for its excellent chemical resistance or polymethylpentene for its transparency, making them lighter and less fragile than glass. Polypropylene (PP) is easy to repeatedly autoclave; however, autoclaving in excess of about 121 °C (250 °F) (depending on the chemical formulation: typical commercial grade polypropylene melts in excess of 177 °C (351 °F)), can warp or damage polypropylene graduated cylinders, affecting accuracy.[1]
Piston ring Most automotive pistons have three rings: The top two, while also controlling oil, are primarily for compression sealing (compression rings). Meanwhile, the lower ring is for controlling the supply of oil to the liner, which lubricates the piston skirt and the compression rings (oil control rings). At least two piston rings are found on most piston and cylinder combinations. Typical compression ring designs will have an essentially rectangular cross section or a keystone (right angled trapezoidal) cross section. The periphery will then have either a barrel profile (for the top compression rings) or a taper napier form (for the second compression ring or scraper ring). There are some taper-faced top rings as well, and on some old engines simple plain-faced rings were used.