1. High structural strength for safety and reliability: Carbon steel or stainless steel reinforced construction provides high pressure resistance, meeting tank operating pressures and external load requirements.
2. Easy opening/closing with labor-saving operation: Equipped with handwheel or screw-type fastening mechanisms combined with hinges, allowing one person to easily open or lock the manhole cover.
3. Reliable sealing with zero leakage: Sealing surfaces use oil-resistant rubber (NBR), fluororubber (FKM), or PTFE gaskets to achieve tight media sealing after closure.
4. Flexible installation options: Flanged connection welded to tank shell; available in elliptical (approx. 300×400mm to 600×800mm) or circular (DN500, DN600) sizes to suit various tank constructions.
5. Corrosion-resistant materials: Body available in carbon steel (with anti-corrosion lining), 304/316L stainless steel; gasket materials suitable for oil products, chemical solvents, water, and other media.
6. Safety and explosion-proof design: Some models may feature explosion-proof locking devices or anti-static bonding to meet fire and explosion protection requirements for petrochemical tank farms.
7. Long service life with easy maintenance: Robust cast or welded construction resists deformation; gaskets are quickly replaceable; hinges and fasteners remain flexible with periodic lubrication.
8. Compliant with national standards: Designed and manufactured according to HG/T 21516 “Turnover cover plate type flanged manholes” or relevant tank accessory standards.