Special Steel Grade Tubing and Casing Since its Foundation, Dynoland has been devoting itself to providing comprehensive and high-quality products and services for global petroleum and gas industry for many years. It can not only provide common steel grade casing and tubing but also provide special steel grade casing and tubing. Special Steel Grade Tubing and Casings from Dynoland are available with the following types and features: ¢ñ. Anti-Collapsing casing series Self-development: High collapsing Series:DL80T¡¢DL90T¡¢DL110T¡¢DL125T¡¢DL130T¡¢DL140T¡¢DL150T¡¢DL155T¡¢DL160T Super High collapsing Series:DL80TT¡¢DL90TT¡¢DL110TT¡¢DL125TT¡¢DL130TT¡¢DL140TT¡¢DL150TT¡¢DL155TT¡¢DL160TT High collapsing + High Anti-Corrosion:DL80TS/DL80TSS¡¢DL90TS/DL90TSS¡¢DL95TS/DL95TSS¡¢DL110TS/DL110TSS