What is TMT?
TMT (Therma Mechenical Treatment) is a technology to produce high strength deformed miled steel bars. Ribbs are not an identification of TMT bars, ribbs are only a design, which helps only in gripping the mixture of cement & concrete. Ribb makes at the time of passing the bars through mill rolls. TMT  process was not using earlier in twisted bars (sariya). It is water quinching system to increase the proof load of the bars, which maintence grade (Fe) of the bar.

What is Fe?
Fe is the proof load of TMT bars. 415/500/550/600 are the yield stress and its unit is N/mm2 . There should not be seen any deformation in the bar during testing process through UTM machine before it's grade. For example Fe-415 means, bar should not be deformed during testing procedure before 415N/mm2. Fe-415 to Fe-499 is covered undet Fe-415 grade.

What is Bend Test?
The test sample in cold condition shall be doubled over the specified mendral by continious pressure until both sides are parallel. The test sample shall be considered to be passed if there is no visible rapture or cracks in bend portion by naked eyes.

What is Re-Bend test?
The test sample shall be bent to an included angle of 135 degree using a mandrel of appropriate diameter.The bent peice shall be aged by keeping in boiling water of 100 degree celcius for 30 minutes and then allowed to cool. The peice shall then be bent back to have an include angle of 157.50 degree. This procedure shpuld be done only one time in one sample. The sample shall be considered passed if there is no visible rapture or cracks by naked eyes on re bent portion.