The composition and production process of hot rolled steel strip for CT70 grade corrosion resistant coiled tubing are independently designed and formulated as well as small batch industrial trial production is carried out. For the trial product, the yield strength is 520~522 MPa, tensile strength is 575~584 MPa, elongation is 33%~34%, microstructure is mainly ferrite +pearlite with a small quantity of bainite, banded structure is grade 1.0 and total of inclusions is grade 1.0 so that non-metallic inclusions are well controlled. The mechanical properties, resistance to hydrogen induced cracking (HIC) and welding performance indexes of steel strip for CT70 as well as the mechanical properties and hardness of coiled tubing manufactured with steel strip for CT70 could all meet the user requirements.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |