Straight thread sleeve is used for mechanical joints to transmit axial tension or pressure of steel bars. Straight thread sleeve is divided into direct rolled straight thread sleeve, stripped rib rolled straight thread sleeve and upsetting straight thread sleeve.

Material requirements for straight thread sleeve:

1. Straight thread sleeve should be made of round steel or seamless steel pipe with grade 45, and its mechanical properties and chemical composition should meet the requirements of GB/T 699, GB/T 8162 regulations. Other steel materials can also be used, and their mechanical properties should meet the requirements of the corresponding national or industry standards and be confirmed by type inspection.

2.  For sleeves that need to be welded with steel such as structural medium steel, the material should meet the weldability requirements.