A mast assembly for a mobile drilling machine may comprise: a mast frame including a back, a first side, and a second side, the first side and the second side diverging from the back to form an open front along substantially an entire length of the mast frame; a drill motor assembly movably attached to the mast frame, wherein the drill motor assembly is configured to rotate a drill pipe; and a drill drive assembly configured to drive the motor assembly up and down along a length of the mast frame, the drill drive assembly including: a sheave assembly comprising a plurality of sheaves, wherein the plurality of sheaves include a first sheave aligned generally parallel to the first side of the mast frame and a second sheave aligned generally parallel to the second side of the mast frame.

Disclosed is a tower lifting device for a rotary blasthole drill, comprising a hydraulic cylinder (5), an extending oil path (7), a retracting oil path (6), a speed control oil path (14) and a proximity switch (3), wherein the extending oil path (7) is connected to a non-rod-end chamber of the hydraulic cylinder (5), and an extension control unit is provided on the extending oil path (7); the retracting oil path (6) is connected to a rod-end chamber of the hydraulic cylinder (5), and a retraction control unit is provided on the retracting oil path (6); the speed control oil path (14) is connected to the retracting oil path (6), the speed control oil path (14) is connected to a speed control valve block (15) in series and the tail end thereof is connected to an oil tank (16); the proximity switch (3) is arranged on a tower supporting frame (2) for controlling the switching on and off of the speed control valve block (15), and when the tower (4) is approximately in a horizontal state, the speed control valve block (15) is on. By using such a tower lifting device in the present invention, the speed at which the tower is laid down to a horizontal state can be conveniently controlled.

The Invention relates to a mast element, in particular leader element, for a construction machine, with an elongate, hollow mast profile, which is approximately rectangular in cross section and comprises a linear guide for a mast carriage on its outer side along a longitudinal direction of the mast. In addition, according to the invention, at least one diagonal reinforcement element extends within the mast profile along the longitudinal direction of the mast, which is arranged at an oblique angle to the sides of the approximately rectangular mast profile.

The invention relates to a civil engineering machine with a undercarriage comprising a track chassis, a superstructure mounted on the undercarriage, so as to be rotatable about a vertical axis of rotation, a leader with a linear guide along which a work carriage with a construction work implement is displaceably mounted, and an articulation mechanism by means of which the leader is adjustably mounted on the superstructure. According to the invention it is provided that the articulation mechanism comprises a telescopic arm by means of which a distance of the leader relative to the superstructure can be adjusted.

A workover rig including a retractable mast, a drawworks system, a drive system, and an electric power assembly. The retractable mast is configured to retract from an extended position into a retracted position for transportation. The drawworks system is configured to control movement of one or more objects suspended from a crown of the retractable mast in the extended position. The drive system is configured to control the drawworks system. The electric power assembly is configured to electrically power and control the drive system. The electric power assembly includes a cooling system.

A drilling rig system includes a mast that includes one or more front legs, one or more rear legs positioned opposite the one or more front legs, and a crown block at the top of the mast. The system also includes a raising line coupled to the crown block or the one or more rear legs and configured to apply a first force to the mast. The first force acts in a direction opposing a second force generated by the weight of the mast as the mast pivots between a substantially horizontal position and a substantially vertical position. The system also includes a drawworks assembly coupled to the raising line and configured to pull the raising line to generate the first force, and a telescoping spring assembly coupled to the one or more front legs. The telescoping spring assembly is configured to apply a third force to the mast that acts in the direction opposing the second force.

A construction machine for special civil engineering has a leader on which an advancing carriage is guided, which carriage has a holder for a work device, in particular a drilling rig or pile-driving implement, and which can be moved along the leader by way of a first advancing cable (upper cable) and a second advancing cable (lower cable), by way of a drive winch or a drive cylinder, wherein the advancing carriage is connected with the advancing cables and wherein at least one of the advancing cables is attached to a fixed point on the leader and/or the advancing carriage, wherein at least one fixed point is formed by a cable tensioner attached to the leader or the advancing carriage. At least one cable tensioner includes a tensioning drum on which an end-side section of an advancing cable is attached with multiple cable windings.

There is provided a mast for a rig, comprising a main boom having a lower end adapted for pivotal connection to a mast support of the rig; and a mast stop extending from the main boom. In use, the mast pivots between a stowed condition and an erect condition, and the mast stop abuts the mast support at a position spaced from the lower end, when the mast is in the erect condition.

A mobile drilling rig is mountable on a separate drive chassis having running gear. A separate main frame may be having elongated members, each having outer end extensions and vertically adjustable support posts thereon. A slide chassis is slidable on one end of the main frame mounting a power plant, and a mast pivot support pivotally mounted on the other end of the main frame. An elongated mast has a drill head movable thereon, with the mast pivot support slidably mounting the mast thereon so that the mast may be pivoted between vertical and horizontal orientations thereon while being movable in lengthwise directions. The slide chassis, the mast and drill head are moved to positions improving the stability of the rig when traversing grades in an up or down hill direction.

A mobile well drilling apparatus for a drilling site with clustered wells includes a substructure. A mast includes hinging points and fixing points. The mast is hinged to the substructure via the hinging points, about which the mast rotates between a horizontal and a vertical position. A drill floor includes a first portion hinged to the mast, and a second portion fixed to the mast and moving integrally therewith; and a draw-works permanently installed on the substructure. The substructure includes first and second sub-bases. The sub-bases are parallel and spaced apart. The first portion of the drill floor includes a connection portion facing one of the sub-bases. The hinging points are connected to one of the sub-bases. In operation, the fixing points are connected to the opposite sub-base. Each sub-base includes hydraulic walking devices adapted to move the well drilling apparatus between the clustered wells on the drilling site.