The raw material of the roundplate is the high -strength HT20-40，whose surface hardnessis of HB170-240,After the two manual handing such as 600℃ to 700℃artificial annealing as well as 2 to 3 years of natural aging, the T-slot hasplate perfectly resists abrasion and has stable precision

Round plate adopts thecoloring method to inspect the machinery parts` geometric tolerance, which isaccurate, intuitive and convenient.