... according to the customer's drawings or samples Material: Ductile iron manhole CoverFeatures:1) Moulding Process: green sand casting, resin sand casting ... ballast, etc.), auto parts, construction and engineering machinery parts, pipe fittings, valve body, fire hydrant, Manhole cover etc. We also supplygray castings as ... number including: QT400, QT500, QT600, QT700; HT250, HT300, TH350 Manhole Cover