1.Specifies the dimensions of those items of the rotary tables for direct rotary drilling equipment which enable the transmission of the rotational motion to the drilling stem.
1.1 The rotary table is designed for suspending various strings used during rig operations, such as drill stem, casing and tubing strings.
IS 12090-1987 history
1988IS 12090-1987 Dimensions of direct rotary drilling tool turret