Di Nicola manufacture gate valves in malleable iron , ductile iron and high nickel alloys for extreme corrosion for over fifty years with sizes from 40 to 1600 mm and nominal pressure 2.5 bar till 25 bar . Di Nicola gate valves are coated with epoxy resins with minimum thickness of 150 micron. marking according to EN ISO 19 and face to face according to DIN 3202 , BS 5150 , ISO 5752 , ASME B16.10 , Flanges dimensioning according to EN 1092. 2 , ISO 2531, BS4504 and various other standards . Di Nicola manufacture non-standard at the request of customers .