mast for oil drilling rig
(JJ90,135, 170, 225,315, 350, 450)
API Spec 4F and API Spec 7K certification
Mast types are including A type, K type (open-front type), derrick, mast and bootstrap etc.
The shape of A-mast section is rectangle or triangle. A-mast has attractive features of high loading capacit... - Update: 2011-12-15