Lockdown screws, (LDS) utilize an external thread (ET) design that moves the threads outside the pressurized or wetted surface of the wellhead equipment. They utilize a robust Unified National Coarse (UNC) thread for the lockdown screw itself and the packing gland nut to minimize any galling. Additionally a one piece HBNR compression packing element with molded metal end caps to provide a dependable seal in multiple pressure ranges and service environments.

They mechanically retain items installed in the bowl of a head that are under pressure.
They can be utilized to energize a compression seal or seals installed in the bowl of a head.
They can be used to prevent an item installed in the head from rotating during the drilling phase of a well.
They retain pressure in the flange of a wellhead assembly.
The lockdown screw itself and the packing gland nut aredesigned with a robust bolt type thread to prevent galling.
They utilize HBNR compression packing with molded metal end caps to provide a dependable seal in multiple pressure ranges and service environments

Lockdown Screw Positions:
Lock Down Screws have the following procedural requirements:

Areeither fully engaged or fully disengaged.

The lockdown screw gland nut cannot be rotated under pressure.

Must only be operated by fully trained and authorized SWS Field ServiceTechnicians.