Abstract: An improved base structure for a derrick mast of a pivotal portable drilling rig structure provides at least two A-frame support members affixed to a rig side of the derrick mast, the drilling rig structure being elevated to a point slightly forward from vertical position towards a well side, with the A-frame support members held in a drilling position by respective support member stanchions which apply static force below the A-frame support members during use of the drilling rig structure applying enhanced drilling forces and stability applied during the drilling process. A rig side secondary locking support structure secured to an elevating drilling rig platform provides additional stability to the drilling rig structure when the drilling rig is in an operational position subsequent to the positioning of the A-frame support members and the support member struts.

Abstract: An improved top drive assembly for a telescoping derrick provides the telescoping derrick with two rectangular telescoping section each defining rear legs and front legs defining a longitudinal channel, each set of front legs further defining rails attached to inner facing surfaces upon which lateral guide tracks of the improved top drive assembly are led, each lateral guide tracks providing a set of parallel channel segments having a friction reducing inner lining and an upper and lower track wheel which travel upon the facing surface of each guide rail for smooth and secure travel up and down the derrick during drilling and completion operations.

Abstract: An improved crown pulley assembly attached to an upper end of a vertical drilling rig derrick mast used in conjunction with an improved top drive assembly which is used within the drilling rig derrick for the drilling of a well, the improved crown pulley assembly having a crown frame supporting a plurality of pulleys with the top drive providing two sets of paired top drive pulleys, the pulleys suspending a single drive cable through the plurality of pulleys with an anchor end of the single drive cable affixed below the derrick and the winch end of the cable attached to a winch to raise and lower the improved top drive assembly within the drilling rig derrick.