VARVO/ TESCO/ CANRIG TOP DRIVE

TOP DRIVE SYSTEM INSTALLATION

AThe AC drilling motors

The TDS-11SA uses two 400 or two 350 HP AC motors mounted vertically side by side on top of the main body to power the TDS-11SA.

The modified D-face attaches the drilling motors to the main body. This mounting method allows installation of the drilling motors without shimming or special alignment. Each motor has a double ended shaft with a drive pinion mounted on the lower end and a disc brake rotor mounted on the upper end. Two hydraulic caliper disc brakes, mounted to the top end of each motor, hold torque in the drill string and assist in positioning during directional work. An electrical solenoid valve remotely operates the hydraulic caliper disc brakes.

The AC drilling motors are an open-frame type, meaning that the cooing air passes through the inside of the motor. The drilling motors, manufactured specifically for top drive applications, have internal temperature sensors, vacuum varnish impregnated windings, high capacity bearing, and tapered output shafts to improve serviceability of the pinion gear and brake hubs.

The motor cooling system on the TDS-11SA is a local intake pressure blower type. It consists of two 5 hp AC motors integrally mounted on top of each AC drilling motor. Air is drawn in from the combination brake cover/air intake and delivered through rigid ducting to an opening in the top of each motor. The cooling air then passes through the inside of the open-frame type AC drilling motors and exits out of louver opening near the bottom of the motors.

The transmission/motor housing (main body) and swivel assembly

The transmission/motor housing and swivel assembly transfers the power produced by the AC drilling motors to the drill string. Inside the transmission/motor housing main body is a single-speed double-reduction gear system that provides a 10.5:1 ratio from the motors to the main shaft.

The main body of the motor housing provides a sealed oil lubrication reservoir for the transmission gears and bearings. Bearings and gears are force fed by an oil pump that is integral with the main body. A low speed hydraulic motor drives the oil pump. The filtered lubrication oil constantly circulates through the main thrust bearing, take-up bearing, lower radial and compound gear bearing and over the gear meshes.

An industry standard wash pipe packing box assembly is located between the main shaft/swivel stem and the S-pipe weldment. The bonnet supports the s-pipe weldment.

The forged alloy steel bail swings forward attaching to standard rotary drilling hooks. The bail is fitted with bronze bushing that are grease lubricated.

Counterbalance system

The counterbalance system includes two hydraulic cylinders connected between the bail and the hook. When the system is activated, the two cylinders support most of the weight of the TDS-11SA. This system protects tool joint threads by taking much of the weight off the drill pipe while making or breaking connections.

An optional feature for the TDS-11SA is called Stand Jump. It consists of a switch at the driller’s console allowing you to change the mode of operation of the counterbalance cylinders from DRILL, which is a standard counterbalance condition, to STAND JUMP. The optional STAND JUMP feature allows the cylinders to lift the weight of the top drive off the drill string while breaking out a connection. This eases the stress on the threads and avoids damage. The cylinders lift the swivel bail off the its resting point on the hook.

The two hydraulic cylinders are connected to a hydro-pneumatic accumulator located on the main body. A manual valve can extend the cylinders to assist during rig-up. The accumulator is charger with hydraulic fluid and maintained at a predetermined pressure setting by the counterbalance circuit in the hydraulic control manifold, located on the main body. The hydraulic manifold controls all hydraulic power to the TDS-11SA.

Carriage and guide beam

The TDS-11SA travels vertically along a guide beam on a carriage attached to the main body. The guide beam hangs from the crown block and extends to within seven feet of the drill floor. The guide beam attaches to a torque reaction spreader beam mounted across the lower section of the mast/derrick, approximately 10-15 feet above the drill floor.

The guide beam counters the drilling torque produced as the transmission turns the drill string. The guide beam comes in sections and requires brackets for mounting to the crown. The guide beam sections are pinned together in such a way the they hinge and can be assembles one section at a time, at the drill floor, and raised to the crown attachment using the TDS-11SA.

Hydraulic control system

The hydraulic control system is a completely self-contained, onboard system. A 10 hp, 1800rpm, AC motor, drives two hydraulic pumps and powers the hydraulic system. A fixed displacement pump drives the lube oil system motor. A variable displacement pump provides hydraulic power for the AC drilling motor brakes, powered rotating head, remote actuated IBOP, pipe backup clamp cylinder, link tilt, and counterbalance system.

The hydraulic manifold attached to the mail body and contains solenoid, pressure and flow control valves.

A sealed stainless steel reservoir supplies hydraulic oil, eliminating the need for draining and refilling during normal rig moves. The reservoir is mounted between the two AC drilling motors and is equipped with strainers and oil level sight gauge.

Three hydro-pneumatic accumulators are located on the mail body. The counterbalance system uses the largest accumulator. The medium size accumulator unloads the variable displacement pump and the smallest accumulator activates the delay circuit on the IBOP actuator.

PH-55 pipehandler

The pipehandle consists of the following major components:

Rotating link adapter

Torque back-up clamp

Two-way link tilt

Internal blowout prevention (IBOP) valves

Elevator links and drill pipe elevator

Rotating link adapter

The powered rotating link adapter, located at the top of the pipehandler, is a slip ring assembly. It allows the hydraulic lines to remain connected as the pipehandler rotates with the drill stem components while tripping out or positioning the link tilt. The rotating link adapter also provides an attachment for the link tilt, pipe backup clamp cylinder, and remote IBOP actuator assembly.

Grooves in the rotating link adapter align with radial holes in the load stem, allowing hydraulic fluid to flow between the rotating link adapter and the load stem as they rotate. The radial passages at the upper end of the load stem intersect with each hose attachment that runs to the hydraulic manifold. The radical passages in the lower end of the load stem intersect with each hose attachment that runs to the hydraulic manifold. The radical passages in the lower end of the load stem intersect sealed grooves in the rotating link adapter that, in turn, connect with hose attachments that run to all the actuators on the pipehandler.

The rotating link adapter is powered in either direction by a hydraulic drive motor. An electric solenoid valve operates the rotating link adapter hydraulic motor.

Torque back-up clamp

The torque back-up clamp is supported by a torque arrestor frame that hangs from the rotating link adapter. The backup clamp is located below the lower shoulder of the saver sub. It consists of a pair of gripping the box end of the tool joint when connected to the saver sub. The backup clamp body is attached to the torque arrestor frame in such a way that it can float up or down to allow for thread engagement and counter backup torque while making and breaking connections.

Two-way link tilt

The two-way link tilt cylinder assemblies consist of the cylinder rods pinned to the rotating link adapter and the cylinder bodies pinned to the links through a set of clamps. Pressurizing the cylinder assemblies by operating the switch on the driller’s console extends the drill pipe elevator to the mouse hole or the drill down position. A float position allows the links to return to well center. The latch on the cylinder assembly limits the travel of the elevator to the derrick man position. Releasing the latch by pulling a cable allows the elevator to travel to the mousehole position.

Internal blowout prevention (IBOP)

The internal blowout prevention (IBOP) control valve contained in the pipehandle is a ball type, full size, internal opening safety valve. A second manually operated lower valve (optional) can be utilized to assist in well control. Both valves bave 6 5/8 in. regular RH connections and 15000 pis pressure ratings.

The remotely controlled upper IBOP valve is opened and closed by a yoke and hydraulic cylinder that is controlled from the driller’s console using an electric solenoid valve. A shell housing rotates with the valve body and moves up and down to drive a small crank arm on each side of the valve stem. The housing is actuated by a cylinder through a non-rotating actuator ring. The hydraulic cylinder is attached to the torque arrestor frame.

The optional lower valve is the same type as the upper except it must be manually opened and closed with a wrench. Both valves remain in the string at all times and are readily available by connecting the TDS-11SA to the drill string. The lower valve can be broken-out from the upper valve using tongs after swinging the torque arrestor frame out of the way.

After breaking-out the lower valve, the TDS-11SA can be hoisted away, allowing room to install the appropriate subs and valves for well control operations. After removing the lower valve from the upper valve on the TDS-11SA using conventional rig tongs, the lower valve remains connected to the drill string for well control purposes. A crossover sub is included with the system to allow connection of the drill stem to the lower valve.

Drill pipe elevator

A drill pipe elevator hangs from a pair of large eye links that attach the link adapter. Actuating the link tilt swings the elevator out to facilitate picking up pipe.

Drill’s console

The varco supplied drill’s console is equipped with the following items to directly interface with the AC frequency drives:

Throttle

The throttle uses a design similar to a standard throttle control supplied with silicone controlled rectifier systems. The handle includes integral stops to prevent damage.

Torque limit potentiometer

The torque limit potentiometer is also similar to the design used on SCR systems. The maximum torque of the drive is limited to the continuous torque rating of the drive and motors.

Makeup limit potentiometer

The makeup limit potentiometer controls the makeup torque when the top drive is used to makeup connections using the drilling motor. This control allows the top drive to operate at the intermittent rating to make up drill pipe connections.

Switches and buttons

Switches and buttons control the following:

Drill, spin, torque mode select

Link tilt

AC drilling motor brake

Backup clamp

Rotating link adapter

Remote IBOP valve

Drill pipe forward/reverse select

Stand jump (optional)

Emergency stop

The driller’s console also includes a horn to warn of an alarm condition.

The driller’s console, made from 300-series stainless steel, used full size oil tight switches and indicators, and is designed for purging to meet hazardous area requirements. The console can be supplied with pyle-national explosion-proof connectors, if requested.

Indicator lights

Indictor lights show the following conditions:

Oil pressure loss

Drill motor overtemperature

Blower loss

IBOP closed

Brake on

Drive fault

Service loops

The TDS-11SA offers the following different service loop configurations designed for different links of rig installations.

One set of 4X646 MCM cables and 2 composite service loops with either a service loop saddle or a derrick-mounted j-box for portable 800 hp UL or Ex units respectively

Two sets of 3X444 MCM cables and 2 composite service loops with a derrick-mounted j-box for non-protable 800 hp UL and Ex units

One sets of 4X646 MCM cables and 2 composite service loops with a derrick-mounted j-box for 700 hp UL and Ex non-protable units

One set of 3X444 MCM cables and 2 composite service loops with a service loop saddle for portable 700 hp UL units

One sets of 4X646 MCM cables and 2 composite service loops with a derrick-mounted j-box for portable 700 hp Ex units

VARVO/ TESCO/ CANRIG TOP DRIVE