A 9-stage, quality-gated production pipeline compliant with ISO 9001:2015. Non-conforming product never advances to the next stage.
Each stage has a defined output standard. Stages marked QC Checkpoint include correction loops — failed items return for rework before proceeding.
High-tensile TMT rebar procured exclusively from certified steel mills. Each incoming lot carries heat numbers, mill certificates, and verified chemical composition records.
Third-party tensile testing of every incoming TMT rebar lot to verify grade — yield strength, UTS, and elongation. Production does not begin until the raw material batch passes independently.
Production run planned to exact order specification: diameter, length, grade, end-type, and quantity. Parameters cross-checked against DGMS Circular No. 3/2010 before scheduling begins.
Fail: Non-optimal parameters trigger a Correction & Optimisation loop. Parameters revised and re-verified before proceeding.
Hot-forged, taper-cut, or Secura ends formed per order specification. A trial run is produced first and checked for dimensional accuracy and visual conformance before the full batch proceeds.
Fail: Dimensional or forging non-conformance triggers a re-run. Trial repeated until pass before batch proceeds.
Precision threading to M20–M27 depending on diameter. Every single bolt undergoes 100% Go/No-Go gauge inspection immediately after threading. No sampling — every bolt is checked before proceeding.
Fail: Thread out of tolerance — non-conforming bolt returned to threading station, re-threaded and re-gauged before advancing.
Pin holes drilled to exact position and diameter per bolt size. Shear pins installed and in-house torque-tested: 70–90 Nm (20 mm), 90–110 Nm (22 mm), 90–130 Nm (25 mm), as per DGMS specification.
Fail: Torque out of range — shear pin replaced and re-tested before the bolt proceeds to final assembly.
Completed assemblies sent to an accredited third-party laboratory for full load testing, shear pin breakout torque verification, and DGMS Circular No. 3/2010 confirmation. No certificate = no dispatch.
Certified assemblies packed as complete sets per customer requirements: roof bolt, W-strap, domed plate, conical seat cum nut, domed washer, nut, and shear pin. All test certificates and MTRs enclosed with every shipment.
Shipment delivered with full batch traceability documentation: DGMS compliance certificates, third-party test reports, and Mill Test Reports in every consignment. PAN India supply to government and private mines.
In the spin-to-stall system, the bolt is spun to mix the resin. Spinning continues until the gelling resin increases resistance, resulting in breakout of the torque nut. The nut runs up the thread and is tightened against the bolt plate in approximately 10 seconds.
The length of exposed thread provides an indication of installation quality. This system gives a simpler underground operation but is more demanding on roof bolting system components. The resin must provide sufficient time for mixing, then transform rapidly from a fluid to a set state, and develop high bond strength.
Our shear pin torque values (70–90, 90–110, 90–130 Nm for 20, 22, 25 mm bolts respectively) are calibrated precisely for this system. The properties of the resin, the breakout torque of the nut, and all other parameters work together — which is why every component of a Manav Engineering assembly is tested before dispatch.
Our team is available to discuss technical specifications, installation requirements, or factory audit arrangements.
