Our Low Temperature products are designed for use in extremely cold environments where brittle behavior is a concern.
Proprietary grades for artic regions and permafrost conditions
Tenaris provides Low Temperature (LT) proprietary steel grades for oil and gas wells in very low temperature conditions, including Arctic regions, where highly effective ductility and fracture toughness are required.
When metals do not have adequate impact toughness and are exposed to low temperatures, they fail in a brittle manner.
Our LT Series grades are available in minimum yield strengths ranging from 55Ksi to 125Ksi. To determine its material toughness, LT products are subjected to charpy testing at -45°C.
Mechanical Properties
| Grade | Minimum Yield Strength (Ksi) | Maximum Yield Strength (Ksi) | MinIMUM Tensile Strength (Ksi) | CVN absorved energy for CL 10 x 10 MM at -45º C |
|---|
| Min. Individual (Joule) | Min. Average (Joule) |
|---|
| TN 55LT |
55 |
90 |
95 |
30 |
40 |
| TN 80LT |
80 |
110 |
100 |
60 |
70 |
| TN 95LT |
95 |
110 |
105 |
50 |
60 |
| TN 110LT |
110 |
140 |
125 |
40 |
50 |
| TN 125LT |
125 |
150 |
135 |
30 |
40 |
| Elongation according to API Formula |
Main features of the LT Series
Normally as yield strength increases, steel toughness decreases. Our Low Temperature (LT) steel grades provide great toughness.
The key factors to achieving this condition are the following:
- Clean steel, containing very low levels of residual elements and oxygen.
- Balanced chemical composition to endure high hardenability.
- Heat treatment process in combination with chemical composition design to ensure a very fine microstructure and high final tempering temperatures to promote the recovery process.