API STD 4
SPECIFICATION FOR STEEL DERRICKS; SUPPLEMENT 1-1976, INCLUDES FORMS 4A1 AUGUST 1962, 4A2 AUGUST 1962, 4B1 AUGUST 1962, 4B2 AUGUST 1962 (WITHDRAWN)
|Publication Date:||1 April 1967|
Coverage. This specification covers steel derricks and steel substructures. It includes stipulations on materials, design features, loadings, and allowable stresses. Recommended practices on the erection, care, and use of steel derricks are included as an appendix.