quenched and tempered steel

NM400 , NM450 , NM500

TW Profile is a supplier of “NM” 400 and “NM” 500 BHN wear resistant Plate. Should the requirement be for locally
produced hardwearing steel T W Profile will source this quality from Mittal Steel South Africa, However Mittal are
only producing the Roqlast 400 BHN quality in thicknesses from 10 mm to 25 mm. T W Profile are currently importing
the 400 and 500 BHN Plate from China under the” NM” 400 and “NM” 500 BHN grades due to the local producer mills
not rolling these items over the last years and importing the “NM” 400 and “NM” 500 BHN were economically viable.

Quality and Hardness

T W Profile ensures when sourcing “NM” 400 and “NM” 500 BHN Plate from international companies, the Plates

conform to the highest national and international specification. Samples of each plate thickness and Quality are

tested by independent Laboratories. All imported “NM” 400 and “NM” 500 BHN Plates conformed to the required

standard. “NM” 400 BHN Plate tested as high as 444 BHN and some “NM” 500 BHN achieved a hardness of 513 BHN.

Further tests were conducted where the through hardness of the plates were tested by “Vickers” hardness test. Both

“NM” 400 BHN and “NM” 500 BHN conformed to the required specification standard.

T W Profile also decided to test these items in the actual application of the plates and sent samples to mines where

Liners were installed in wet and dry conditions. All Liners tested performed as expected and the performance was on

par with other Liners sourced from European steel mills.

Structural and wear application

T W Profile supplied our customer Wingdale engineering with 40 mm and 50 mm “NM” 400 BHN Grizzly Plates for
the Konkola north Copper project. The items were cut to a total length of 4600 mm and 500 x 500 x 40 mm join plates
were welded in place with a 40 x 40 mm weld with very high heat transfer. The plates were tested after the welding
process was completed around the welds and the hardness exceeded the required hardness of “NM” 400 BHN by
testing 444 BHN

Cutting and Countersinking

T W Profile will cut the Liners to customer requirements with Laser, High Definition Plasma or Flame. Our
countersinking department consists of four radial arm drills and three automated work stations, this capacity
ensures fast and efficient service to our customers on small and large orders. Stringent quality control procedures
are followed to ensure Liners are countersunk to meet and even exceed customer expectations. Each liner is
individually inspected, neatly packed on wood Pallets and plastic wrapped for dispatch.
Stringent controls are enforced to ensure all plates are furnished with the correct test certificate. These controls are
further applied to ensure the Liners supplied are furnished with the correct Mill test certificate and are traceable
back to the mother plate. The test certificate also confirms the Chemical composition, Tensile test and impact tests
done on the plate

Designation and Chemical Composition

Mechanical Property