Oil & Gas .

A two- or three-stage parallel-shaft gearbox with a herringbone output stage transmits torque from the drive motor to the winch drum. Rigs with 100–500 metric tons hook load are built around CGC ZSY/ZLY gearboxes rated for at least 25,000 hours of service life. Reversing duty during tripping requires careful rotor balancing and tolerance for angular misalignment of the output shaft toward the gear coupling to the drum.

• Gear ratio 8–25
• Output torque 80–600 kN·m at hook load
• Service factor ≥ 1.8 for drilling, ≥ 2.0 for workover/well-servicing
• Reversing duty up to 30 cycles per hour
• Forced circulating lubrication with oil cooler

A bevel or bevel-helical gearbox with a built-in gear coupling to the cardan shaft from the drawworks. It delivers up to 60 kN·m on the rotary table at 0–250 rpm, with reversing duty during fishing and reaming. On modern top-drive rigs the rotary table is a back-up, but the gearbox must still cope with the full drilling cycle.

• Output torque 30–60 kN·m
• Loaded reversals up to 50 cycles per shift
• Gear coupling on the input-shaft side
• Seals protected against drilling-mud ingress

An alternative to the V-belt drive — an integrated gearbox between the motor and the triplex pump. It is used on modern FA/FB-series pumps rated 1,600–2,200 kW. A single housing makes for a more compact layout and less maintenance (no periodic belt replacement), but it requires careful shaft alignment and foundation vibration damping.

• Gear ratio 4.5–6.5 (motor 750–1,000 rpm → pump 100–150 rpm)
• Output torque 150–250 kN·m
• Service factor ≥ 1.5
• Vibration-isolating mounts under the foundation

BONENG K- and F-series gear motors drive cuttings conveyors, shale shakers, centrifuges and slurry pumps in mud-cleaning circuits. Continuous S1 duty in dust and oil mist. Seal resistance to oil-based drilling mud is critical.

• Power 1.5–75 kW
• K-series (bevel-helical) or F-series (parallel-shaft)
• NBR/FKM seals resistant to hydrocarbons
• IP55 protection, tropical-climate execution

A single-stage parallel-shaft or coaxial speed-up gearbox is installed between the 6/10 kV HV motor and the main oil pipeline pump when the motor is low-speed and the pump is rated for 3,000–4,500 rpm. Continuous S1 duty, G2.5 rotor balancing, and a forced-lubrication oil-cooling unit are required.

• Gear ratio 1.5–3.5 (speed-up)
• G2.5 rotor balancing
• Forced lubrication with filtration and cooling
• Vibration monitoring per ISO 10816-3

High-voltage asynchronous or synchronous motors of 2,000–8,000 kW at 6 or 10 kV. Continuous S1 duty; capacity control through an HV variable-frequency drive saves up to 25% of electricity compared with valve throttling. WOLONG WD3000 and YHTM series with forced water cooling are rated for 24/7 operation over 8,000 hours between maintenance intervals.

• Rated power 2,000–8,000 kW, voltage 6/10 kV
• Rated efficiency no lower than 96%
• VFD-compatible (Class H insulation)
• Insulated bearing on the non-coupling end
• Vibration, winding and bearing temperature monitoring (Pt100)

Electric-driven GPUs are an alternative to gas turbines, economically attractive when grid capacity reserves are available and discharge pressure is 6.3–7.5 MPa. Synchronous motors of 6,300–32,000 kW at 10 kV with brushless excitation are typical. Capacity control via an HV variable-frequency drive is critical for variable-flow operation.

• Rated power 6,300–32,000 kW, voltage 10/11 kV
• Synchronous with brushless exciter (predominantly)
• Speed 1,500–5,500 rpm matched to the centrifugal compressor
• Forced cooling IC81W (water-to-air) or IC616 (air-to-air)
• HV-inverter compatibility per NEMA MG1 Part 31

Modern drilling rigs are powered by 600–2,200 kW drives distributed between drawworks, mud pumps and rotary table. Both DC machines with thyristor control (legacy rigs) and AC motors with HV inverters (new rigs) are used. WOLONG supplies motors of both categories, including explosion-proof YBX3 series for the wellhead area where gas releases are possible.

• Rated power 600–2,200 kW, voltage 0.69 kV or 6 kV
• Starting torque ≥ 1.8× rated under string load
• S4 thermal reserve — 60 starts per hour during tripping
• Ex-rated YBX3 execution (Ex d IIB T4) for the wellhead area
• Forced ventilation with cooling-air reserve

One of the most loaded drives on a rig — an 800–2,200 kW mud-pump motor running in S1 duty while delivering 30–60 L/s of drilling fluid at pressures up to 35 MPa. Both asynchronous WOLONG YE/YBX3 machines at 6 kV and DC motors for legacy rigs are used. Starting is performed via a soft starter or direct on-line when the section has sufficient capacity.

• Rated power 800–2,200 kW
• Continuous S1 duty over the well's drilling cycle (30–90 days)
• Optional Ex-rated execution for rigs close to the wellhead
• Class F insulation with Class B temperature rise reserve
• IP55 minimum, protected against dust and oil mist

A band or disc brake on the winch drum, controlled by the driller through a lever and a pad with a pneumatic/hydraulic booster. Modern rigs are equipped with HUAWU DBS multi-caliper water-cooled disc brakes that allow string-lowering speed to be controlled without overheating. Legacy rigs use band brakes with friction blocks.

• Braking torque margin of 1.75–2.0× peak hook load
• Water cooling of brake discs (for disc brakes)
• Hydraulic or pneumatic actuator booster
• Friction-pad service life of at least 200 trips
• Stepped lowering-speed control

A spring-applied, hydraulically released disc brake — a separate set independent of the service brake. On loss of power, on an emergency-stop press or on exceeding the lowering-speed setpoint (typically 1.5× rated), the brake closes automatically within 0.15–0.3 s. HUAWU YPZ2/SBD and ZHONGHAI SB series are sized to hold the full string load and are certified to API 7K.

• Spring-applied, hydraulically released
• Closing time on loss of power ≤ 0.3 s
• Braking torque ≥ 1.75× full string load
• Pad-wear and position monitoring (limit switches)
• API 7K or GOST R 53364 certification

The wellhead area of an open-cycle well is a place where gas releases are possible during reservoir work, so brakes on workover and well-servicing units are supplied in Ex-rated execution: ZHONGHAI SBD-Ex, HUAWU YWZ-Ex with a dual closing system. The workover winch itself is less powerful than a drawworks (30–80 metric tons hook load), but the requirement for two independent brakes still holds.

• Ex d IIB T4 for the wellhead area
• Two-brake arrangement (service + emergency)
• Braking-torque margin of 1.75× rated
• Resistance to weather and salt mist on offshore platforms
• Manual release option for string evacuation

TKT/TKK shoe brakes with electro-hydraulic thrusters are installed on the high-speed shaft between motor and gearbox/sheave. Their job is to stop the pump rotor on loss of power and prevent reverse fluid flow through the pump. They are also used on the rotary-table drive to lock the string for make-up/break-out.

• Electro-hydraulic thruster Ed-50 to Ed-301
• Closing time ≤ 0.5 s
• Manual release option for maintenance
• Pad-wear monitoring (limit switch)

YONGJING GIICL and LONGXUAN WGZ are double-engagement drum-type gear couplings transmitting up to 600 kN·m with compensation of radial and angular misalignment. They are installed between the drawworks gearbox and the drum, and between the cardan shaft and the rotary-table gearbox. The crowned tooth form allows operation at angular misalignment up to 1.5°, which is critical for thermal growth of housings after several hours of tripping.

• Torque 50–600 kN·m
• Angular misalignment up to 1.5°
• Grease lubrication via grease nipple, 6-month interval
• API 7K certification for drilling duty

YONGJING SWP/SWC are universal-type cardan drives connecting the gearbox to the rotary table or top drive. They accommodate significant axial travel (up to 200 mm) and angular misalignment (up to 10° per joint), needed to compensate travelling-block stroke and thermal deformations.

• Torque 30–200 kN·m
• Permissible joint angle up to 10°
• Forged-steel spiders with rolling-element bearings
• Balancing per GOST 22061-76 above 500 rpm

JIAOHUA YOX/COX are oil-filled fluid couplings that provide soft starting of triplex pumps under load and protect the motor from overload during water hammer or discharge-line blockage. Rated slip is 2–3%; a fusible plug set at 145–160 °C dumps oil overboard on overheat. They are especially justified with direct on-line motor starting (without a soft starter or VFD).

• Rated slip 2–4%
• Fusible plug set at 145–160 °C
• Oil fill 70–85% of internal volume
• Thermal capacity for 4–6 loaded starts per hour

LONGXUAN LX (LMC) and YONGJING LMS are pin-and-bushing couplings with elastomer sleeves connecting motors to pumps. They damp starting shocks and torque pulsations from piston pumps. On main oil pipeline pumps they are often combined with a shear-pin safety coupling, which protects the gearbox and the motor if the impeller jams.

• Torque 5–125 kN·m
• Radial misalignment compensation 0.2–1.0 mm
• Elastomer service life of at least 30,000 hours
• Optional shear-pin safety element