Bi-Lobe: Maximum Solid Clearance
Bi-lobe rotary pump geometry provides maximum internal pocket clearances for large gravel, fibers, soft solid chunks, and thick primary sewage sludge.
Drive, seal protection, shaft support, and rotor geometry
Rotary Lobe Pump Structural Design
Explore optional reduction gears, the isolation chamber, shaft support, and rotor profiles. See how these components affect installation space, seal protection, and application fit.
1. Built-In Reduction Gearbox (Optional)
YANESS offers an optional factory-fitted speed-reduction gear set inside the pump drive housing. It lets a standard-speed motor drive the rotors at the lower speed required by the duty, without a separate external reducer or geared motor.
This arrangement can shorten the package and reduce alignment work associated with an external reducer. A standard-speed motor generally has a lower purchase cost than a geared motor.
Drive housing: Optional built-in reduction gears (inside the drive housing when specified)
Coupling: Direct motor coupling (no separate reducer coupling in this layout)
Motor: Standard-speed motor (e.g. 4-pole / 6-pole)
- Drive housing: Optional built-in reduction gears (inside the drive housing when specified)
- Coupling: Direct motor coupling (no separate reducer coupling in this layout)
- Motor: Standard-speed motor (e.g. 4-pole / 6-pole)
For the displacement cycle and the role of timing gears, see the rotary lobe pump working principle.
2. Intermediate Isolation Chamber
YANESS places a dedicated oil-filled intermediate isolation chamber between the wet end and the dry gearbox. The barrier fluid helps cool and lubricate the seals, and gives leakage a visible path through indicator ports before process media reaches the gear oil.
Wet End
Contains the process medium being pumped.
Mechanical seal
Isolation Chamber
Oil-filled chamber supporting seal cooling and lubrication.
Leakage indicator port: visible detection if the process seal leaks.
Lip seal
Timing Gearbox
Gears and bearings run in gear oil, separate from the process medium.
For operating limits and monitoring around seal lubrication, review dry-run capability and protection.
3. Shaft Support: Double-Support Default
Under high viscosity or higher differential pressure, rotors see heavy radial loads. Double-support is the YANESS default: bearings on both sides of the rotors help hold alignment, reduce shaft deflection, and protect seal and bearing life on abrasive or high-pressure duties. The front support is integrated into the pump cover, keeping the arrangement compact. Single-support remains available for duties that prioritise a simpler structure.
Shaft Support Layout Under Radial Load
Single-Support (Available Option)
One-Side Bearing Support
Bearings
Rotor↓ Radial Force
- Simpler package: Shorter wet-end path and easier access on standard duties.
- Deflection risk: High viscosity or pressure can bend the unsupported shaft end.
- When to use: Milder duties where compactness and simple service matter more than peak rigidity.
Double-Support (Default)
Bearings on Both Sides of the Rotor
Bearing A
Rotor↓ Radial Force
Bearing B
- Lower deflection: Shaft is held at both ends, reducing flex under radial load.
- Seal alignment: Helps keep mechanical seal faces stable in demanding service.
- Clearance control: Helps maintain rotor-to-rotor clearances on high-pressure or abrasive duties.
4. Rotor Lobe Profiles
YANESS rotary lobe pumps are not limited to one rotor configuration. Rotor lobe geometry can be reviewed around solids size, pulsation tolerance, viscosity, abrasion, cleaning method, and target flow behavior.
Helical Tri-Lobe: Pulsation-Free Dosing
Helical tri-lobe geometry uses three twisted lobes to smooth continuous flow in dosing, filling, polymer transfer, and other shear-sensitive duties.
Tri-Lobe: Symmetrical Self-Priming
Tri-lobe standard geometry balances self-priming behavior, solids passage, and moderate pulsation control for oil sweeps and general sludge.
Compare rotor types and design tradeoffs, then check wetted materials and elastomer compatibility for the fluid and cleaning conditions.
After structural review
Drawings & Pump Sizing Support
Next is usually dimensional drawings for installation fit, or a duty review for torque, speed, and shaft-support selection.
Brochure & Project Drawings
Download the brochure for standard model dimensions. Request STEP, DWG, or package layout drawings for your project configuration.
Request Pump Sizing
Send fluid, flow, pressure, and site limits. YANESS reviews torque, speed ratio, and shaft-support fit before recommending a model.