HPLPA114 & HPLPA Series Hydraulic Internal Gear Pump

The HPL, HPLPA, HPLMA, and HPLPT series high-pressure internal gear hydraulic pumps manufactured by LIC Hydraulic (comprehensively matching specific engineering codes such as HPLPA114HDDG3G3B00, HPLPA114, HPLPA131, HPLPA148, and HPLPA180) are state-of-the-art fluid power units engineered for modern industrial automation, injection molding machinery, and responsive servo-drive dynamic networks. Conforming fully to standard SAE mounting patterns, input drive shafts (keyed or splined), fluid port threads, and volumetric performance curves, this entire pump platform delivers 100% drop-in interchangeability with standard international HPL/HPLPA series high-pressure internal gear pumps.

Standard external gear pumps operating above 200 bar typically introduce severe pressure ripples, audible high-frequency noise, and accelerated volumetric decline as lateral wear plates degrade. LIC overcomes these operational flaws by implementing an advanced radial and axial pressure-adaptive gap compensation system leveraging a precision-profiled crescent element. Every single pump assembly undergoes 100% full-load simulated high-frequency servo operational factory testing before dispatch. Sustaining a high volumetric efficiency above 96% under continuous pressures up to 300 bar with an exceptionally quiet runtime, our pumps represent a premium procurement alternative for global B2B distributors, HPU builders, and system integrators.

Technical Specifications

Accurate engineering parameters based on standard industrial internal gear pump catalog criteria:

• Product Series: HPL / HPLPA / HPLMA / HPLPT High-Pressure Internal Gear Pump Platform

• Displacement Profiles Sizing:

  • HPLPA114: Nominal displacement of 14.0 cm³/rev

  • HPLPA131: Nominal displacement of 31.0 cm³/rev

  • HPLPA148: Nominal displacement of 48.0 cm³/rev

  • HPLPA180: Nominal displacement of 80.0 cm³/rev

• Full Model Code Breakdown Example (HPLPA114HDDG3G3B00):

  • HPLPA114: Denoting HPLPA series high-pressure platform with a 14.0 cm³/rev configuration.

  • HDD: Heavy-duty shaft profile arrangement (e.g., standard SAE A straight keyed or splined extension matching high-load internal bearings).

  • G3G3: Designated intake and pressure port thread specifications (e.g., standard G3/4″ or specific SAE split-flange ports).

  • B00: Clockwise (Right-hand) rotation standard with a modular plain rear cover layout.

• Maximum Continuous Operating Pressure: Up to 250-280 bar (3625-4060 psi)

• Maximum Intermittent Peak Pressure: Up to 300-315 bar (4350-4568 psi)

• Operating Speed Boundaries: 600 rpm – 3000 rpm (Optimized for sudden acceleration/deceleration cycles of variable-speed servo motors)

• Fluid Medium Compatibility: Mineral-based anti-wear hydraulic oil, matching thermal conditions from -10°C to +80°C.

• Main Housing Construction: High-yield extruded aluminum or premium heavy ductile iron (dependent on displacement sizing classes).

Key Technical Advantages

• Bi-Directional Hydrostatic Gap Sealing Compensation: The internal axial sealing plates and the radial crescent sealing elements are subtly energized by high-pressure fluid routed from the outlet port. This forces the components to dynamically conform against the gear faces and tips, shrinking volumetric clearances to near zero. This mechanism guarantees steady pressure containment and high efficiency even during low-speed hold-pressure operation.

• Straight Conjugate Tooth Geometry (Minimal Pressure Ripple): Utilizes a specialized straight-line conjugate internal tooth profile machined on precision CNC gear shapers. The internal and external gears provide a high contact ratio during engagement, avoiding dead-volume fluid trapping. This architecture lowers fluid pressure ripples close to zero, reducing airborne running noise by 15-20 dB compared to external gear units.

• Optimized Performance for Variable-Speed Servo Systems: Features low rotational mass inertia and excellent responsiveness to sudden rotational velocity transitions. When subjected to repetitive servo-motor cycles of “start-accelerate-decelerate-reverse-hold”, the inner friction interfaces adjust rapidly without causing heat friction spikes or mechanical seizing at low speeds (down to 600 rpm).

• Thru-Drive Modular Multi-Stage Combination: The HPLPA and HPLMA series exhibit highly versatile through-drive rear covers. This allows multiple pumps of varying or identical displacements to be coupled together directly without bulky intermediate adapter kits, reducing the envelope footprint inside overcrowded machine compartments.

Application Areas

The HPL/HPLPA series internal gear hydraulic pumps deliver low noise output, exceptional pressure holding stability, and robust servo compatibility in critical automation systems:

• Precision Plastics & Rubber Injection Molding Machinery: Main fluid power loop supplying fast clamping, injection velocity, and multi-stage holding profiles.

• CNC Automated Press Brakes & Metal Stamping Presses: Providing swift flow acceleration coupled with absolute pressure repeatability for complex metal forming.

• High-Volume Leather, Shoe, & Industrial Vulcanizing Presses: Ensuring minimal thermal energy conversion and low power loss during prolonged pressure clamping stages.

• Primary Heavy-Duty Stationary Hydraulic Power Units (HPUs): Serving as a vibration-free pilot or main flow supplier feeding high-sensitivity proportional or servo valve manifolds.

Expert Maintenance Tips

• Mandatory Initial Priming to Prevent Instant Face Scuffing: Internal gear pumps feature extremely close running clearances. Prior to firing up a newly replaced pump (such as HPLPA114HDDG3G3B00), pre-fill the pump internal housing completely with clean anti-wear hydraulic oil through the suction or pressure ports and rotate the shaft by hand. Firing up the unit dry will immediately score the internal crescent and tooth tips, rendering the gap compensation mechanism useless.

• Zero Air Ingress Allowed; Secure Suction Piping Sealing Completely: Internal gear pumps are highly vulnerable to aerated fluid. Ensure all suction line connections use perfect gaskets and remain airtight. If air leaks into the suction stream or if a clogged suction strainer triggers cavitation, collapsing air bubbles under high pressure will pit the crescent face, causing a surge in operating noise and immediate efficiency loss.

• Maintain Highly Rigid Solid Contamination Barriers: Because of the precision-machined adaptive floating plates, fine abrasive dust trapped in the fluid will score the running faces and lock the compensation plates. Enforce rigid filtration standards to hold oil cleanliness parameters to ISO 4406 19/17/14 or better. Replace aging fluid promptly if it begins to varnish, avoiding mechanical stiction within the compensation components.