Helical gear gear reducer

precisionhigh-performancehigh-speed

Overview
Lufkin Gears integrally geared solutions are custom-designed gearboxes engineered for high performance, robustness, and long-term reliability. Each unit is delivered with full engineering support to meet complex design and integration needs. These gearboxes are capable of handling heavy impeller housings while minimizing vibration and can be designed to meet API 613 and API 617 standards and ATEX where required.

Benefits

• 100+ years of engineering expertise, innovation, field-support experience, and customized solutions worldwide
• High-stiffness, ultra-compact solutions with reduced weight and ultra-low noise and vibration characteristics
• Customization options enabling a high degree of flexibility for integration with complex shaft-line configurations

Features

• Integral or shrunk-on collars capable of withstanding very high sliding velocities while supporting external process forces
• Pinion shafts can be supplied with Hirth teeth; integrated shaft-driven oil feed pump options to ensure lubrication under all operating conditions
• Design and performance validation via rotor-dynamics (including impellers cross-coupling), finite element analysis (casing modal), and specific running tests

Applications

• Air and other gas compression with electric motor or turbine drivers; suitable for energy recovery with turbo-expanders driving generators
• Pinion speeds up to 50,000 rpm; power transmission up to 25 MW; gear ratios up to 15:1
• Applicable across chemical and oil & gas industries including gas compression, air separation, power generation and carbon capture

Gear teeth and thrust collar
Gearing is typically single-helical for better axial end-play control, with double-helical options where appropriate. Single-helical designs use integral or shrunk-on thrust collars to eliminate redundant thrust bearings on high-speed pinions, improving efficiency. Gear teeth are precision ground and can be modified to correct torsional and bending contact mismatches. Heat-treatment options include case-hardening, nitriding, or through-hardening as required.

Gear casing
Casings are custom-designed and validated by finite element analysis to meet turbo equipment mounting and loading requirements. Casing covers can be designed for dismantling without removing the impeller casing. Bearings may be internally constrained so gear elements remain located if the cover is removed. Casings are fabricated from heavy steel plate for stiffness and long life. Oil-pump mounting solutions are available as shaft-driven or offset-mounted on the casing.

Bearings
Multiple bearing design options are available to suit application needs, including sleeve bearings, taper-land thrust bearings, tilt-pad journal bearings, tilt-pad thrust bearings, and integral squeeze-film damper bearings.

Stability
Units are engineered for stability by custom-tuning pinions to operate away from critical speeds. Design work includes establishing impeller and seal weight/inertia requirements and impellers cross-coupling data to ensure trouble-free operation. Undamped, damped, and stability analyses can be provided in accordance with API 613 and API 617.

Condition monitoring
Condition monitoring solutions such as Bently Nevada (or equivalent) can be provided on all shafts to monitor radial and axial vibration and phase angle. Magnetic speed pickups can be mounted to sense gear teeth or a gear with a specific tooth count. Embedded simplex and duplex RTDs or thermocouples are used for bearing temperature monitoring.

Technical specifications

• Model / denomination: Integrally Geared Solutions
• Pinion speed: up to 50,000 rpm
• Power transmission: up to 25 MW
• Maximum gear ratio: up to 15:1
• Standards: design available to meet API 613, API 617; ATEX options available
• Gear types: single-helical (typical) or double-helical
• Thrust collar: integral or shrunk-on
• Gear material & treatments: case-hardening, nitriding, through-hardening as required
• Bearing options: sleeve, taper-land thrust, tilt-pad journal, tilt-pad thrust, integral squeeze-film damper
• Validation & analysis: rotor-dynamics, FEA (casing modal), running tests; undamped/damped stability analyses available
• Condition monitoring: vibration probes, phase sensing, magnetic speed pickups, RTDs/thermocouples for bearing temperature