AFL AlumaCore OPGW (Optical Ground Wire) is preferred for its central aluminum pipe and color-coded fiber optic buffer tubes which simplify the splicing process while providing optimum fiber protection as well as long term product reliability. Optical Ground Wire (OPGW) is a dual functioning cable. The Aluminium tube is surrounded by single or double layers of aluminium clad steel wires (ACS) or mix ACS wires and aluminium alloy wires. ●Short circuit. ainless steel and aluminium. Electrical and mechanical ace unit for optical fibres. The fibres are loosely buffered in a tube containing an oval, spiralling, holl channel filled with jelly. The loose tube construction prevents fibre strain. ZTT OPGW is mainly divided into: central-type stainless steel tube OPGW, stranded-type stainless steel tube OPGW, al-covered stainless steel tube OPGW, aluminum tube OPGW, lightning resistant central stainless steel tube OPGW with compressed wires and OPPC. Stainless steel tube OPGW: stainless. An optical ground wire (also known as an OPGW or, in the IEEE standard, an optical fiber composite overhead ground wire) is a type of cable that is used in overhead power lines. The outer layer is designed with an optimized combination of Aluminum-Clad Steel (ACS) and All-Aluminum (AA) wires to meet specific.