FULL THREADED RE BAR, ROCK BOLT, MINING TUNNEL APPLICATION
Rock bolts are widely used for rock reinforcement in mining and tunneling. Our heat-treated rebars have big advantage on yield strength, tensile strength and pre-stress, which could help to support underground tunnels, roof support.
Steel grade: 20MnSi
SCREW-THREAD RE BARS FOR PRE-STRESSING OF CONCRETE
The bar portion of rock bolt, is called as screw-thread steel bars, mostly applying for pre-stressing of concrete, which has dis-continuous threads with high strength, high precise, and can be anchored directly by nuts or internal threaded connectors/coupler. <br>
We divide the fully thread bars by the yield strength – Code PSB + minimum yield strength(eg: PSB830). P, S, B represent Prestressing, Screw-thread, bars, and 830 means this rebars’ standard yield strength is 830 MPa.
|Strength Class||Yield Strength, Rel/Mpa||Tensile Strength,(Rm/Mpa)||Elongation after fracture, A/%|
Nominal diameter range : 18 ~50 mm
25mm, 32mm is the mostly common diameters.
Rebar lengths are often fixed according to orders. Length tolerance is 0~+50mm; Cutting length tolerance is 0~+20mm;
Curving degree shall be less than 0.4% rebar’s total length, and less than 4mm per meter.
top ends must be flat and smooth, to ensure nuts or connectors/coupers passing through.
|Nominal Diameter, mm||Nominal Cross Section Area, mm²||Theoretical Weight. kg/m|
|Theoretical weight in this table is according to steel density 7.85g/cmm³.|