Internal Connection 

Vacuum insulated tubular has a variety of forms to meet the needs of different oil well conditions. It can be divided into three types according to the end connection mode: external connection, internal connection and direct connection.  

Sanjack has three heat insulation technologies for the manufacture of vacuum insulated tubular, namely, double-wall structure, thermal radiation shielding, and thermal convection blocking, with excellent performance of heat insulation pipe. 

The sealing annulus is in a vacuum state with getter in it and it can clean the polluted air and extend the service life of the insulation tubing. 

Internal connections could reduce the OD of tubing string, without procedure of upsetting, expending or heat treatment. It will be a better choice for small size of casing, because the connection is located on internal pipe. Two coupling options for reference. One is regular couplings with insulated sleeve and the other is vacuum insulated coupling. The Internal connection Vacuum insulated tubular owns advantages as follows: 

• Connections on inner pipes; 
• With Regular couplings or vacuum insulated coupling; 
• Plus outer insulation sleeves between connections;