ST800 Steel Cord Conveyor Belt

CBC India's ST800 steel cord conveyor belt addresses the tensile and operational demands that push the ST630 grade to its engineering limits. The classification is precise: per DIN 22131 and ISO 283, the "800" designates a guaranteed minimum breaking strength of 800 Newtons per millimeter of belt width — a 27% tensile increase over the ST630 that translates directly into greater working tension capacity, longer haul distances, and higher tonnage throughput without proportional increases in belt width or drive power.

Construction

The ST800's load-bearing structure is built around galvanized steel cords in 6×7 or 6×19 strand configurations, with individual cord diameters of 3.0–3.5 mm and a cord pitch of 10–12 mm center-to-center. Each cord delivers a minimum breaking force of approximately 8.9 kN, brass-bonded to the skim rubber compound during vulcanization for adhesion integrity across millions of bending cycles. Total belt thickness runs approximately 25 mm, with a reference mass of 19.5 kg/m² — a weight profile that supports reduced pulley sizing and lower structural loading on conveyor frameworks compared to heavier fabric constructions at equivalent tensile ratings.

Top and bottom covers are specified at 5 mm each, compounded to DIN Grade W, Y, or Z depending on the abrasion, cut, and tear resistance profile required by the conveyed material. Flame-retardant and antistatic variants comply with ISO 284, EN 16974, and DIN 22102, making the ST800 a qualified specification for underground mining and enclosed gallery installations. Standard widths span 800 mm to 2,400 mm, with roll lengths up to 350 m per section.

Performance

Working elongation remains below 0.25% at rated tension, consistent with the ST-class standard and directly enabling longer center distances between pulleys without excessive take-up travel. Operating tensions reach up to 685 PIW, with conveying speeds to 6.0 m/s across single-flight spans of 1–2 km handling iron ore, coal, limestone, and crushed aggregates up to 300 mm lump size. Deep troughability — a product of the cord array's controlled lateral flexibility — increases cross-sectional belt loading by 20–30% over stiffer constructions, reducing spillage at transfer points. Against equivalent-width fabric ply belts, the ST800 reduces drive power requirements by 15–25% through lower carcass mass and compatibility with smaller minimum pulley diameters of 800–1,000 mm.

Installation and Maintenance

Hot-vulcanized step splices per DIN 22131 Part 3 deliver 100% joint efficiency at every cord. In-service cord integrity monitoring is performed using magnetic flux leakage or X-ray scanning — both non-destructive methods that identify internal wire breaks without belt removal. With structured inspection intervals and rip detection systems in continuous operation, ST800 belts achieve a documented service life of 7–12 years in port, power plant, cement plant, and surface mining applications.

Technical specification of ST800 Conveyor Belt

Standard Steel Cord Conveyor belt Range As per DIN 22131

Available Stocks of ST800 conveyor belt