Hyloc Hydrotechnic Pvt. Ltd. Manufactures Flanges. Hyloc Hydrotechnic Pvt. Ltd. Is an ISO 9001:2008 and ISO 14001:2004 accredited company. The Flanges are of various types like Solid, Swivel, Socket and Blind Flanges etc. Available in a large number of standard and custom configurations in steel as well as stainless steel.