|DSI Underground Grades||tensile strength (ASTM-D4595)||tensile strength (ASTM-D4595)||tensile strength (ASTM-D4595)||tensile strength (ASTM-D4595)||tensile strength (ASTM-D4595)||minimum aperture size||weight (ASTM-D5261)|
at 2% strain1
at 2% strain1
|55/55||440||440||55||55||18 x 23%||1.30||33||12||375|
|55/55||440||440||55||55||18 x 23%||2.40||60||12||375|
|80/80||650||650||80||80||18 x 23%||1.25||31||15||500|
|80/80||650||650||80||80||18 x 23%||2.40||60||15||500|
|200/80||1,600||650||200||80||18 x 23%||1.25||31||23||780|
|200/200||1,600||1,600||200||200||18 x 23%||1.05||26||38||1288|
MD = machine direction, XMD = Cross Machine Direction
1 2% strain is equivalent to 10" convergence given 10ft unsupported span during shield recovery.
Polymesh is comprised of high tenacity yarns, woven into a stable interlocking grid structure and then coated with PVC for protection during installation.
Polymesh is used for longwall recovery mats as well as rib control. Longwall recovery mats are fabricated and assembled to mine-specifications.
- Light weight - reduces cost and handling time.
- No sharp edges, reducing injury hazard associated with chain link and welded wire.
- Conforms easily to the roof or ribs due to the multifilament yarn design.
- Stronger than other polymer grids: Since the longitudinal and transverse members are crossed and independent, there is less ripping out at the intersections than with other polymer grids.
Polymesh is available in rolls made to custom length. The typical roll lengths are 30 m, 50 m and 100 m.The width also can be customized to specific needs but common are 1.25 m and 2.5 m with 5 m being the maximum width.