TMT Rebars
TMT stands for Thermo Mechanically Treated.
TMT Bars are used in construction and integral part of any structure or building. It can be bend and used as per requirement in site and reinforced with concrete.
Basically there are 3 Qualities in bars:-
- CTD :- Cold Twisted Deformed Bars
- TOR :- Tor – 40
- TMT :- Thermo-Mechanically Treated Bars
CTD & TOR-40:
CTD & TOR -40 are old forms of reinforcement bars but are now obsolete because CTD name itself suggests that it is “cold twisted deformed” bars. And it is twisted when it is cold, which leads to surface crack which makes the product more prone to corrosion. TMT Bars are much easily available and is of superior quality than CTD & TOR-40.
TMT Bars:
Representation of TMT bars is done by its diameter.
For e.g.: 8mm TMT bar means diameter of that bar is 8mm.
Sizes:-
Following are the sizes available in Reinforcement bars:
Diameter (in mm): 8, 10, 12, 16, 18, 20, 25, 28, 32, 40, 45.
Grades of TMT Bars:-
Specifications:
| Standard | Grade | Remarks |
| IS 1786-1985 | FE- 415 | – |
| IS 1786-1985 | FE- 500 | – |
| IS 1786-1985 | FE- 550 | – |
| Re-Bars with corrosion resistant element |
CRM | Cu+Cr+P = 0.75 % min |
| HSCRM | Cu+Cr+P = 0.75 % min | |
| Earth Quake resistance | EQR |
Specifications:
| Yield Strength N/mm2 (min) | UTS N/mm2 (min) | % Elongation (min) |
| 415 | 485 | 14.5 |
| 500 | 545 | 12 |
| 550 | 585 | 8 |
| 415 | 485 | 14.5 |
| 500 | 545 | 12 |
| 14. 5 |
Manufacturers of TMT bars:–
There are broadly 2 types of Manufacturers
- Primary
- Secondary
Primary Manufacturers :- Primary Producers are those who have fully integrated plants (i.e. plants which have their own sources of Iron-ore, Blast furnace, Sponge iron plant, Power plant & Finished product plant.) In India there are mainly 4 Primary producers of TMT Bars which are as follows:-
- SAIL
- VIZAG (also known as RINL : Rashtriya Ispat Nigam Limited)
- TATA
- Jindal
Secondary Manufacturers –
- General specification
- Thickness: 8mm – 40mm
- Length: 12m (straight)
| Specification | End Use | |
| IS Equivalent | ||
| TMT PLUS Fe-415 | IS 1786 – Fe 415 | construction, concrete reinforcement, bridges flyovers, infrastructure, industrial building etc. |
| TMT PLUS Fe-500 | IS 1786 – Fe 500 | |
| TMT PLUS Fe-550 | IS 1786 – Fe 550 | |
| TMT PLUS CRS | IS 1786 HCR | corrosive, humid & marine areas, bridges, dams, roofing etc. |