What PLB stands for
Permanently Lubricated. A HDPE pipe with an integral solid-silicone inner layer that reduces friction for cable blowing over long distances.
Standard sizes
Three common sizes: 32/26 mm (OD/ID), 40/33 mm, 50/42 mm. 40/33 mm is the workhorse for city and highway OFC.
Working pressure
Typically 12.5 bar for cable blowing. Every duct is hydrostatic tested before dispatch.
Approvals
TEC/GR/TX/CDS-008/03 (MAR-2011) and IS 14930 (Part 2). Mandatory for BSNL, RailTel, PGCIL and BharatNet.
Colour coding
Standard colours: orange, yellow, blue, green, red, black. Custom stripes and network markings on order.
Cable blowing
Coefficient of friction < 0.1 enables OFC blowing over 2 km at a stretch. Trained blowing crew and calibrated equipment are essential for consistent results.
