FOREWORD (a) This specification was prepared by the API Committee on the Standardization of Standard Rigs and Derricks and is recommended for the use of the oil industry in all districts of the United States. (b) This specification covers dimensional and strength requirements of steel and wood derricks@ rig and derrick parts@ derrick sub-structures@ pumper structures@ bolts@ and capacity ratings for roller bearings. (c) Revisions: This specification can be revised at any time by regular Committee action@ or@ in order to care for changes which may prove necessary on account of obvious errors or inconsistencies@ upon approval bythe Engineers' Subcommittee@ the matter may be referred at once by letter to the membership of the various Committees that have been active in drawing the specifications@ and a letter ballot taken on the proposed change@ which may then be made effective at once. (d) Another specification issued by this Committee is the following: 4-A: Rig Iron Standards (Covers dimensional data for standard rig irons.)
API STD 4-1944 history
1944API STD 4-1944 SPECIFICATION FOR STANDARD RIGS AND DERRICKS AND ACCESSORY EQUIPMENT (Twelfth Edition; Incorporates Supplement 1: June 1946)
1942API STD 4-1942 SPECIFICATION FOR STANDARD RIGS@ DERRICKS@ AND ACCESSORY EQUIPMENT (ELEVENTH EDITION)
1940API STD 4-1940 SPECIFICATION FOR STANDARD RIGS AND DERRICKS (Tenth Edition)
1936API STD 4-1936 SPECIFICATIONS FOR STANDARD RIGS AND DERRICKS (Eighth Edition; Supp No. 1: September@ 1937)
1935API STD 4-1935 SPECIFICATIONS FOR STANDARD RIGS AND DERRICKS (Seventh Edition)
1934API STD 4-1934 SPECIFICATIONS FOR STANDARD RIGS AND DERRICKS (Sixth Edition; SUPP 1: September 1934)
1931API STD 4-1931 SPECIFICATIONS FOR STANDARD RIGS AND DERRICKS (FIFTH EDITION)
1930API STD 4-1930 SPECIFICATIONS FOR STANDARD RIGS AND DERRICKS (Fourth Edition; SUPP 1: February@ 1931)
1927API STD 4-1927 Standard Rigs and Derricks (First Edition)