Gear pump
HENGYUHANG Hydraulic Power Unit Gear Pump HGP-1A Series
Engineered with high-tensile extruded aluminum alloy body, precision-ground hardened alloy steel gears, and self-compensating bush lobe balance seals, the HENGYUHANG HGP-1A Series micro hydraulic gear pump delivers exceptional volumetric efficiency (≥ 93%), ultra-low operating noise, and dependable fluid power with working pressure up to 210 kgf/cm² (210 bar / 3,000 psi) and maximum peak pressure up to 250 kgf/cm² (250 bar / 3,500 psi).
| Applications
Designed specifically for micro and mini AC/DC hydraulic power packs (HPUs), mobile equipment, and precision industrial systems, the HGP-1A Series powers compact scissor lifts, auto car lifts, truck tailgates, hospital medical beds, dental chairs, machine tool lubrication, solar trackers, and miniature robotic actuators. Featuring standardized SAE 2-bolt (2B), DIN 4-bolt (4BDA/4BDB), and European 4-bolt (4BE) mounting flanges with straight keyed (X), splined (Y), and tapered (Z) shafts alongside versatile threaded (PT/BSPP/NPT/UNF) and flanged (F1/F2) ports, it provides direct 1:1 drop-in interchangeability across global hydraulic systems.
| Key Technical Specifications
Product Model: Hengyuhang Hydraulic Power Unit Gear Pump HGP-1A Series
Brand Replacement: HydroMax, RexPower, Yuken, Kompass, Winner, Shimadzu, Casappa, Marzocchi, Parker OEM or as requested.
Displacement: 0.5 to 7.8 cm³/rev across 10 standardized models (HGP-1A-05, 08, 1, 2, 26, 3, 4, 5, 6, 8)
Rotation Direction: Clockwise (R), counter-clockwise (L), and bi-directional hydraulic motor (M) (viewed looking at drive shaft end)
Speed Range: Minimum speed 600 to 1,000 r/min; Rated speed 1,800 r/min; Maximum permissible speed up to 3,200 to 4,500 r/min
Peak Pressure: Rated working pressure 170 to 210 kgf/cm² (170 to 210 bar); Maximum peak pressure up to 210 to 250 kgf/cm² (210 to 250 bar / 3,500 psi)
- Description
- Tecspecs
- Brand & Reference
- Download HENGYUHANG HGP-1A Hydraulic Power Unit Gear Pump PDF
- Send an Inquiry
| Overview of HENGYUHANG HGP-1A Series Hydraulic Gear Pumps
The HENGYUHANG HGP-1A Series represents an industry-standard, ultra-compact high-efficiency external positive displacement gear pump engineered specifically for mini and micro hydraulic power packs, mobile scissor lifts, commercial vehicle tailgates, medical positioning equipment, and precision machine tools. Built across 10 finely stepped displacements — ranging from 0.5 cm³/rev up to 7.8 cm³/rev — the HGP-1A pump delivers smooth flow rates from 0.9 l/min up to 14.04 l/min at rated 1,800 r/min, accommodating continuous working pressures up to 210 kgf/cm² (210 bar / 3,000 psi) and peak spike pressures up to 250 kgf/cm² (250 bar / 3,500 psi).
Manufactured with high-tensile extruded aircraft-grade aluminum alloy housings paired with rigid precision-machined front and rear end covers, the pump exhibits outstanding resistance to high cyclic pressure fatigue and structural deformation while keeping the overall pump weight exceptionally light (between 1.0 kg and 1.4 kg). The internal power transmission features case-hardened, carburized alloy steel gears with micro-finished tooth profiles that ensure minimal flow pulsation, ultra-quiet running decibels (< 58 dBA), and exceptional mechanical efficiency. High-load DU composite journal bushings provide self-lubricating hydrodynamic support under continuous load, while advanced hydrostatic pressure-balanced lobe seals dynamically compensate for axial clearances across varying fluid temperatures and operating pressures. This maintains superior volumetric efficiency (≥ 93%) throughout extended duty cycles in demanding industrial and mobile applications.
| Dimension of HENGYUHANG HGP-1A Series Hydraulic Gear Pumps
| Interface Data Needed with the Drawing Across the 10 Models
| Interface / Feature Item | Engineering Specification & Dimensional Callout | Standard Options & Details |
|---|---|---|
| Mounting Flange Option 1 | Code 2B — SAE 2-Bolt Flange | Pilot spigot diameter: Ø 50.8 mm (+0 / −0.05 mm); Spigot height: 3.8 mm; Two-bolt center pitch: 82.55 mm; Flange overall width: 103.5 mm; Mounting holes: 2-Ø 11 mm |
| Mounting Flange Option 2 | Code 4BDA — DIN 4-Bolt Flange (Type A) | Pilot spigot diameter: Ø 25.4 mm (+0 / −0.05 mm); Spigot height: 3.8 mm; Bolt pattern: 56 mm × 73 mm (also 52.4 mm × 71.9 mm); Mounting through-holes: 8-Ø 7 mm |
| Mounting Flange Option 3 | Code 4BDB — DIN 4-Bolt Flange (Type B) | Pilot spigot diameter: Ø 30.0 mm (+0 / −0.05 mm); Spigot height: 3.8 mm; Bolt pattern: 56 mm × 73 mm (also 52.4 mm × 71.9 mm); Mounting through-holes: 8-Ø 7 mm |
| Mounting Flange Option 4 | Code 4BE — European 4-Bolt Flange | Pilot spigot diameter: Ø 30.0 mm (+0 / −0.05 mm); Spigot height: 3.8 mm; Bolt pattern: 4-Ø 7 mm on square 40 mm × 40 mm and rectangular 56 mm × 73 mm; Overall width: 64 mm × 80 mm |
| Mounting Flange Option 5 | Code L — Foot Bracket Mounting | Heavy-duty foot mounting bracket for direct baseplate or electric motor pedestal installation |
| Drive Shaft Option 1: Straight Keyed | Code X1 — Straight Cylindrical Shaft | Shaft diameter: Ø 12.0 mm (+0 / −0.02 mm); Woodruff key size: 4 × 16 mm; Keyway height: 13.4 mm (+0 / −0.2 mm); Extension length: 25 mm (overall 28 mm for 2B) |
| Drive Shaft Option 2: Straight Keyed | Code X2 — Straight Cylindrical Shaft | Shaft diameter: Ø 12.7 mm (+0 / −0.02 mm / 1/2 in); Woodruff key size: 3.175 × 19 mm; Keyway height: 14.0 mm (+0 / −0.2 mm); Extension length: 25 mm (overall 28 mm for 2B) |
| Drive Shaft Option 3: Straight Keyed | Code X3 — Straight Cylindrical Shaft | Shaft diameter: Ø 10.0 mm (+0 / −0.02 mm); Woodruff key size: 3 × 13 mm; Keyway height: 11.20 mm (+0 / −0.2 mm); Extension length: 25 mm (overall 36 mm for 2B) |
| Drive Shaft Option 4: Splined | Code Y1 — Involute Splined Shaft | Spline specification: 9T × 20/40DP × 30° pressure angle; Spline length: 25 mm (overall 27.7 mm for 2B) |
| Drive Shaft Option 5: Splined | Code Y2 — Involute Splined Shaft | Spline specification: 15T × 20/40DP × 30° pressure angle; Spline length: 18 mm (overall 22 mm for 2B) |
| Drive Shaft Option 6: Tapered | Code Z1 — 1:8 European Taper Shaft | Taper ratio: 1:8; Threaded end: M7 × P1.0 with hex nut and lock washer; Woodruff key size: 2.4 mm / 3 × 13 mm; Extension length: 25 mm (overall 28 mm for 2B) |
| Threaded Ports Option 1 (PT / BSPT) | Code P (P1, P2) | P1 (0.8–6 cc): Inlet 3/8" PT, Outlet 3/8" PT; P2 (7.8 cc): Inlet 1/2" PT, Outlet 3/8" PT |
| Threaded Ports Option 2 (G / BSPP / PF) | Code G (G1, G2) | G1 (0.8–6 cc): Inlet G 3/8", Outlet G 3/8"; G2 (7.8 cc): Inlet G 1/2", Outlet G 3/8" |
| Threaded Ports Option 3 (NPT) | Code N (N1, N2) | N1 (0.8–6 cc): Inlet 3/8" NPT, Outlet 3/8" NPT; N2 (7.8 cc): Inlet 1/2" NPT, Outlet 3/8" NPT |
| Threaded Ports Option 4 (UNF O-Ring) | Code U (U1, U2) | U1 (0.8–6 cc): Inlet 9/16"-18UNF, Outlet 9/16"-18UNF; U2 (7.8 cc): Inlet 3/4"-16UNF, Outlet 9/16"-18UNF |
| Flanged Ports Option (F1, F2) | Code F1, F2 — Diamond Flanged Ports | F1: Orifice Ø 14.50 mm, 2-bolt circle 30 mm (M6 thread); F2: Orifice Ø 14.50 mm, 2-bolt circle 35 mm (M6 thread) |
| Direction of Rotation | Code R, L, M | R: Clockwise viewed looking at drive shaft end; L: Counter-clockwise; M: Bi-directional hydraulic motor |
| Pump Installation Specifications
| Modular Model Ordering Code Structure
HGP−1A−F−□−□−□−□−□
HGP−1A−[Mounting]−[Displacement]−[Rotation]−[Shaft]−[Flange]−[Port]
| Position / Segment | Code Element | Description & Available Options |
|---|---|---|
| 1. Model Series | HGP-1A | Ultra-compact micro hydraulic power pack gear pump series |
| 2. Mounting Type | F, L | F = Flange mounting type (standard); L = Foot bracket mounting type |
| 3. Delivery Capacity | 05 to 8 | Nominal displacement (cm³/rev): 05 = 0.5 (custom); 08 = 0.8; 1 = 1.0; 2 = 2.0; 26 = 2.6 (custom); 3 = 3.0; 4 = 4.0; 5 = 5.0; 6 = 6.0; 8 = 7.8 |
| 4. Rotation Direction | R, L, M | R = Clockwise (viewed looking at drive shaft); L = Counter-clockwise; M = Bi-directional hydraulic motor |
| 5. Drive Shaft Type | X, Y, Z | X1 = Straight shaft Ø12.0 mm (4 × 16 key); X2 = Straight shaft Ø12.7 mm (1/2 in); X3 = Straight shaft Ø10.0 mm (3 × 13 key); Y1 = Splined shaft 9T (20/40DP); Y2 = Splined shaft 15T (20/40DP); Z1 = Tapered shaft (1:8 taper with M7 × P1.0 nut) |
| 6. Flange Mounting Type | 2B, 4BDA, 4BDB, 4BE | 2B = SAE 2-bolt flange (pilot Ø50.8 mm, pitch 82.55 mm); 4BDA = DIN 4-bolt flange Type A (pilot Ø25.4 mm); 4BDB = DIN 4-bolt flange Type B (pilot Ø30.0 mm); 4BE = European 4-bolt flange (pilot Ø30.0 mm) |
| 7. Inlet & Outlet Port Type | P, G, N, U, F | P (P1, P2) = PT/BSPT taper thread (3/8" or 1/2"); G (G1, G2) = BSPP/G internal thread (G3/8" or G1/2"); N (N1, N2) = NPT thread (3/8" or 1/2"); U (U1, U2) = UNF O-ring boss thread (9/16"-18 or 3/4"-16); F (F1, F2) = Diamond flanged ports (M6 bolt circle) |
| Reading Your Replacement Code
| Target Brand & Part Number | HENGYUHANG HGP-1A Equivalent | Fitment & Direct Interchange Verification |
|---|---|---|
| HydroMax HGP-1A-F-08-R-X1-4BDA-P1 | HGP-1A-F-08-R-X1-4BDA-P1 | 100% exact 1:1 drop-in replacement: 0.8 cc/rev, DIN 4BDA flange, straight shaft X1, 3/8" PT ports |
| HydroMax HGP-1A-F-2-R-X1-2B-G1 | HGP-1A-F-2-R-X1-2B-G1 | Direct fit for 2.0 cc/rev scissor lift and power unit pumps, SAE 2B flange, G3/8" ports |
| HydroMax HGP-1A-F-4-R-Z1-4BE-P1 | HGP-1A-F-4-R-Z1-4BE-P1 | Exact match: 4.0 cc/rev, European 4BE flange, 1:8 taper shaft Z1, 3/8" PT ports |
| HydroMax HGP-1A-F-8-R-Y1-2B-P2 | HGP-1A-F-8-R-Y1-2B-P2 | High-displacement 7.8 cc/rev micro pump, rated 170 kgf/cm² (170 bar / 2,450 psi), 1/2" PT inlet |
| RexPower HGP-1A-F-1-R-X2-2B-U1 | HGP-1A-F-1-R-X2-2B-U1 | 1.0 cc/rev, 1/2" shaft X2, SAE 2-bolt flange 2B, 9/16"-18UNF O-ring ports |
| Yuken / Kompass HGP-1A Series | HGP-1A Series (Matching Code) | Exact dimensional pilot, bolt pattern, and displacement parity across machine tool lubrication packs |
| Casappa Polaris PLP05 / PLP10 | HGP-1A Series (Custom Spec) | Equivalent micro displacement and pressure performance across Group 0.5/1 compact applications |
| Marzocchi Micropump ALP05 Series | HGP-1A-F-4BE Series | Direct European 4-bolt and 1:8 taper fitment replacement for Group 0.5 aluminum micro gear pumps |
Techspecs of HENGYUHANG HGP-1A Series
4.1 Performance Data Across 10 Displacements
| Model Number | Accurate Displacement (cc/rev) | Operational Pressure (kgf/cm² / bar) | Maximum Pressure (kgf/cm² / bar) | Rated Speed (r/min) | Maximum Speed (r/min) | Minimum Speed (r/min) | Flow at Rated Speed (l/min) | Pump Weight (kg) |
|---|---|---|---|---|---|---|---|---|
| HGP-1A-05 | 0.5 | 210 / 210 | 250 / 250 | 1,800 | 4,500 | 1,000 | 0.90 | 1.00 |
| HGP-1A-08 | 0.8 | 210 / 210 | 250 / 250 | 1,800 | 4,500 | 1,000 | 1.44 | 1.00 |
| HGP-1A-1 | 1.0 | 210 / 210 | 250 / 250 | 1,800 | 4,500 | 1,000 | 1.80 | 1.00 |
| HGP-1A-2 | 2.0 | 210 / 210 | 250 / 250 | 1,800 | 4,500 | 600 | 3.60 | 1.05 |
| HGP-1A-26 | 2.6 | 210 / 210 | 250 / 250 | 1,800 | 4,500 | 600 | 4.68 | 1.15 |
| HGP-1A-3 | 3.0 | 210 / 210 | 250 / 250 | 1,800 | 4,500 | 600 | 5.40 | 1.15 |
| HGP-1A-4 | 4.0 | 210 / 210 | 250 / 250 | 1,800 | 4,000 | 600 | 7.20 | 1.18 |
| HGP-1A-5 | 5.0 | 210 / 210 | 250 / 250 | 1,800 | 3,200 | 600 | 9.00 | 1.20 |
| HGP-1A-6 | 6.0 | 210 / 210 | 250 / 250 | 1,800 | 3,200 | 600 | 10.80 | 1.30 |
| HGP-1A-8 | 7.8 | 170 / 170 | 210 / 210 | 1,800 | 3,200 | 600 | 14.04 | 1.40 |
Note: Models HGP-1A-05 (0.5 cc/rev) and HGP-1A-26 (2.6 cc/rev) are specialized configurations; customized production service is readily provided upon request.
4.2 Operating Pressure & Speed Limits
| Parameter | Permissible Operational Limit | Engineering Operating Conditions |
|---|---|---|
| Rated Operational Pressure | 170 to 210 kgf/cm² (17.0 to 21.0 MPa) | Continuous permissible working pressure (210 bar for 0.5–6 cc; 170 bar for 7.8 cc) |
| Maximum Peak Pressure | 210 to 250 kgf/cm² (21.0 to 25.0 MPa / up to 3,500 psi) | Permissible transient pressure spikes during intermittent cycle peaks |
| Speed Range Limits | 600 to 4,500 r/min | Rated operating speed: 1,800 r/min; max speed up to 4,500 r/min on micro frames |
| Suction Port Inlet Pressure | −0.03 to +0.03 MPa (−0.3 to +0.3 bar) | Measured at pump inlet to ensure complete self-priming without cavitation |
| Volumetric Efficiency | ≥93% | Maintained across rated speeds with optimal fluid viscosity |
4.3 Fluid & Filtration Specifications
| Parameter | Permissible Operating Limits | Optimal Recommended Target |
|---|---|---|
| Recommended Hydraulic Fluid | Anti-wear mineral hydraulic oil (ISO VG 32 / VG 46 / VG 68; HM / HV) | High-quality HM 32 / HM 46 anti-wear hydraulic oil |
| Operating Viscosity Range | ν=10 to 300 mm²/s (cSt) | νₒₚₜ=20 to 50 mm²/s (cSt) |
| Operating Fluid Temperature | −15 ∘C to +80 ∘C (+5 ∘F to +176 ∘F) | +30 ∘C to +55 ∘C (+86 ∘F to +131 ∘F) |
| Filtration Rating (Suction Line) | ≤100 μm wire mesh suction filter | Protects against coarse particulate contamination |
| Filtration Rating (Pressure / Return) | ≤25 μm (β₂₅≥75) | Target fluid cleanliness: ISO 4406 Class 19/16 |
Advantages of HENGYUHANG HGP-1A Series Hydraulic Gear Pumps
Hydrostatic Axial Pressure Clearance Compensation
Equipped with precision bush lobe seals and back-up rings that utilize discharge pressure to provide automatic axial clearance compensation, sustaining high volumetric efficiency (≥93%) over thousands of duty hours.
Carburized Alloy Steel Gears with Micro-Finish Precision
Gears are manufactured from high-grade alloy steel, vacuum carburized, and CNC-ground to ensure minimum flow pulsation, ultra-low operating decibels (<58 dBA at 1,500 rpm), and outstanding wear life.
Ultra-Lightweight Aircraft-Grade Aluminum Construction
High-tensile extruded aluminum body delivers superior power-to-weight ratio (pump weight between 1.0 kg and 1.4 kg), rapid heat dissipation, and excellent fatigue resistance under high-pressure cycling.
Heavy-Duty DU Composite Self-Lubricating Bushings
Advanced PTFE/DU composite journal bearings absorb continuous radial loads with minimal friction, delivering dependable operation under intermittent boundary lubrication and heavy starting torque.
Multi-Flange, Multi-Shaft & Multi-Port Modularity
Standardized SAE 2-bolt (2B), DIN 4-bolt (4BDA/4BDB), and European 4-bolt (4BE) mounting interfaces accommodate straight keyed (X1–X3), splined (Y1, Y2), and tapered (Z1) shafts alongside PT, BSPP, NPT, UNF, and flanged ports to fit any compact power pack design.
100% Factory Dynamometer Tested
Every manufactured pump undergoes rigorous end-of-line testing for pressure hold, flow output, volumetric efficiency, and internal seal integrity, guaranteeing immediate 1:1 drop-in replacement across international brands.
Reference
6.1 Displacement & Model Matrix
Displacements Available: 0.5, 0.8, 1.0, 2.0, 2.6, 3.0, 4.0, 5.0, 6.0, and 7.8 cm³/rev.
Mounting Configurations:
2B: SAE 2-bolt flange (pilot Ø50.8 mm, pitch 82.55 mm, 2-Ø11 mm holes).
4BDA: DIN 4-bolt flange Type A (pilot Ø25.4 mm, 8-Ø7 mm holes, 56×73 mm).
4BDB: DIN 4-bolt flange Type B (pilot Ø30.0 mm, 8-Ø7 mm holes, 56×73 mm).
4BE: European 4-bolt flange (pilot Ø30.0 mm, 4-Ø7 mm holes, 56×73 mm / 40×40 mm).
L: Foot mounting bracket.
Drive Shaft Configurations:
Straight Keyed (X1): Ø12.0 mm (+0/−0.02), woodruff key 4×16 mm, length 25 mm (28 mm for 2B).
Straight Keyed (X2): Ø12.7 mm (1/2 in), woodruff key 3.175×19 mm, length 25 mm (28 mm for 2B).
Straight Keyed (X3): Ø10.0 mm, woodruff key 3×13 mm, length 25 mm (36 mm for 2B).
Splined (Y1): 9T × 20/40DP × 30° pressure angle, length 25 mm (27.7 mm for 2B).
Splined (Y2): 15T × 20/40DP × 30° pressure angle, length 18 mm (22 mm for 2B).
Tapered (Z1): 1:8 European taper, M7×P1.0 threaded end with nut, woodruff key 2.4 mm / 3×13 mm.
Port Configurations:
P (PT / BSPT): P1 (Inlet 3/8" PT, Outlet 3/8" PT), P2 (Inlet 1/2" PT, Outlet 3/8" PT).
G (G / BSPP / PF): G1 (Inlet G 3/8", Outlet G 3/8"), G2 (Inlet G 1/2", Outlet G 3/8").
N (NPT): N1 (Inlet 3/8" NPT, Outlet 3/8" NPT), N2 (Inlet 1/2" NPT, Outlet 3/8" NPT).
U (UNF): U1 (Inlet 9/16"-18UNF, Outlet 9/16"-18UNF), U2 (Inlet 3/4"-16UNF, Outlet 9/16"-18UNF).
F (Flange): F1 (bolt circle 30 mm, M6), F2 (bolt circle 35 mm, M6).
6.2 Target Brand Interchangeability Matrix
The HENGYUHANG HGP-1A Series offers direct 1:1 functional, hydraulic, and dimensional replacement across premier global gear pump manufacturers:
HydroMax Hydraulics: 100% direct 1:1 drop-in for HGP-1A Series across all displacements (0.5 to 7.8 cc/rev), flange types, and shaft codes.
RexPower & Winner Hydraulics: Direct interchange for micro and mini AC/DC hydraulic power pack pumps.
Yuken & Kompass: Complete interchangeability for machine tool lubrication, clamping, and industrial hydraulic power units.
Monarch / Haldex / Concentric: Direct replacement for compact 12V/24V DC power unit pumps.
Shimadzu & Kayaba Group 0.5/1: Direct replacement for small industrial and mobile auxiliary pumps.
Casappa (Polaris PLP05 / PLP10 Series): Direct functional and displacement match across micro industrial applications.
Marzocchi (ALP05 / GHP05 Series): Direct fitment replacement for Group 0.5 aluminum micro gear pumps.
Brand Replacement & Interchangeability
The HENGYUHANG HGP-1A Series gear pump is built to exact international manufacturing tolerances, ensuring seamless 1:1 mechanical and hydraulic replacement for HydroMax, RexPower, Yuken, and European Group 0.5/1 pumps. Every critical mounting parameter—including spigot pilot diameters (Ø50.8 mm for SAE 2B; Ø25.4 mm / Ø30.0 mm for DIN 4BD and European 4BE), bolt patterns, drive shaft extensions (straight shafts Ø12.0 mm, Ø12.7 mm, Ø10.0 mm; splines 9T and 15T; 1:8 tapered), and port thread locations—is identical to OEM specifications.
This guarantees effortless drop-in installation onto existing electric motor bell housings, DC motor power units, and hydraulic manifold blocks without mechanical alterations, adapters, or hydraulic line modifications. Machinery manufacturers, service repair centers, and fluid power distributors benefit from substantial procurement savings, expedited delivery timelines, and field-proven reliability.
Applications
Micro & Mini Hydraulic Power Packs (AC & DC HPUs): Primary pressure source for compact power packs used in lift tables, mobile cranes, and portable hydraulic equipment.
Truck Tail Lifts & Commercial Vehicle Gates: Hydraulic lifting and lowering power for commercial truck hydraulic tailgates and wheelchair lift vans.
Compact Scissor Lifts & Aerial Work Platforms: High-reliability lifting hydraulics for micro scissor lifts and self-propelled aerial work platforms.
Medical Equipment & Hospital Patient Beds: Smooth, ultra-quiet hydraulic actuation for surgical tables, hospital positioning beds, and dental examination chairs.
Auto Car Lifts & Motorcycle Service Platforms: Standard hydraulic supply for low-rise automotive service lifts, tire changers, and motorcycle lifting racks.
Machine Tools & Automation Lubrication Systems: Lubrication, clamping fixtures, indexing tables, and auxiliary hydraulic circuits in precision metalworking machines.
Package & Shipping
| Packaging Construction | Individual heavy-duty reinforced corrugated carton with custom-molded shockproof EPE foam inserts; batch wholesale shipments packed in standard export fumigation-free wooden crates |
| Corrosion Protection | Internal test fluid coating, external corrosion-inhibiting treatment, and heat-sealed vapor corrosion inhibitor (VCI) plastic enclosure |
| Port & Shaft Protection | Custom heavy-duty plastic threaded plugs for all inlet and outlet ports, and rigid protective plastic sleeves for drive shaft extensions |
| Individual Pump Weight | 1.00 kg (HGP-1A-05) up to 1.40 kg (HGP-1A-8) |
| Standard Dispatch Lead Time | Standard catalog models dispatched within 48–72 hours from warehouse inventory; volume custom OEM batches dispatched in 10–15 business days |
| Global Shipping Options | Air express delivery (DHL, FedEx, UPS, TNT) for urgent maintenance; Ocean container (FCL/LCL) and dedicated Air freight for volume commercial distributors |
| Export Documentation | Factory dynamometer quality inspection certificate, CE conformity documentation, and customized OEM private-label branding supported |
Why Choose Hengyuhang?
Direct Factory Precision Manufacturing & CNC Excellence: Manufactured in our state-of-the-art production plant equipped with high-precision 4-axis and 5-axis CNC machining centers, automated high-speed gear hobbing machines, and precision gear tooth flank grinders (Ra < 0.2 μm) ensuring microscopic internal clearances, ultra-quiet operation, and peak volumetric efficiency.
100% Full-Cycle Multi-Parameter Factory Inspection: Every single pump is tested on computerized dynamometer test benches, verifying volumetric efficiency (≥93%), flow output across rated rpm, continuous and peak pressure hold, internal bypass, and sound pressure levels. Zero untested units leave the factory.
Seamless 1:1 OEM Drop-In Interchangeability: Dimensionally and hydraulically calibrated to global industry standards, guaranteeing direct 1:1 mechanical drop-in replacement across HydroMax, RexPower, Yuken, Casappa, and Marzocchi pumps without piping or bracket modifications.
Flexible Engineering Customization & Rapid Prototyping: Backed by an experienced fluid power engineering team capable of customizing displacements, non-standard shaft extensions, specialized flange bolt circles, integrated relief valves, and tandem pump configurations with low MOQ requirements and rapid sample turnaround.
Robust Supply Chain, Extensive Inventory & Fast Global Dispatch: Substantial raw material inventory of extruded high-tensile aluminum profiles, ductile iron castings, hardened gear blanks, and seal kits enables lightning-fast 48–72 hour dispatch for emergency breakdown replacements, supported by complete global export logistics.
12-Month Comprehensive Warranty & Lifetime Technical Support: All pumps are backed by our 12-month full-coverage manufacturer warranty against defects in materials and craftsmanship, supplemented by 24/7 technical consultation, 2D/3D CAD model verification, and dedicated fluid power engineering support.
HENGYUHANG Hydraulic Power Unit Gear Pump HGP-1A Series (High-Pressure External Micro Hydraulic Gear Pump, 0.50~7.80 cc/rev) is an ultra-compact, high-efficiency micro external hydraulic gear pump engineered specifically for mini hydraulic power packs (HPU), compact AC/DC power units, automotive tail lifts, patient transfer beds, and precision industrial automation fixtures. Manufactured by Quanzhou Hengyuhang Power Technology Co., Ltd., the HGP-1A Series combines a high-tensile extruded aluminum alloy gear housing with rigid, precision-machined cast iron front and rear covers, high-grade alloy steel case-hardened precision gear sets, and heavy-duty DU composite self-lubricating sleeve bushings. The pump features an advanced pressure-balanced bush lobe seal and elastomeric back-up ring compensation system that provides automatic axial and radial clearance compensation, ensuring sustained high volumetric efficiency (≥ 92%), low startup friction torque, and whisper-quiet, pulsation-free fluid delivery across continuous high-pressure duty cycles. Operating at nominal continuous working pressures up to 210 kgf/cm² (21 MPa / 210 bar / 3,000 psi) and maximum peak pressures up to 250 kgf/cm² (25 MPa / 250 bar / 3,500 psi), the HGP-1A Series covers 10 standardized displacement ratings—0.5, 0.8, 1.0, 2.0, 2.6, 3.0, 4.0, 5.0, 6.0, and 7.8 cc/rev (mL/r)—with maximum drive speeds reaching up to 4500 r.p.m. and total unit weight under 1.4 kg. Engineered for seamless integration into compact power pack manifold blocks, electric motor bell housings, and mini machinery chassis, the HGP-1A offers four standardized mounting flange configurations (SAE 2-bolt 2B, European 4-bolt 4BE, and DIN 4-bolt 4BDA / 4BDB), diverse drive shaft profiles (straight keyed X1~X3, involute splined Y1~Y2, and 1:8 tapered Z1), and multi-standard fluid ports (diamond flange F1~F2, G/BSPP, PT/BSPT, NPT, and SAE/UNF O-ring boss), providing an ultra-reliable, high-pressure fluid power solution for mini power pack builders, car lift manufacturers, medical equipment engineers, and automation machine designers.
| Applications
The HGP-1A Series micro hydraulic gear pump is designed for compact, space-constrained fluid power units and light-duty mobile lifting equipment requiring smooth, high-pressure hydraulic performance:
Mini Hydraulic Power Packs & AC/DC Power Units: Serves as the primary high-pressure delivery pump in compact modular power packs for mini scissor lifts, personal car hoists, and mobile hydraulic tools.
Commercial Vehicle Tailgate Lifts & Ramp Deployers: Powers compact electro-hydraulic power units for delivery van tail lifts, wheelchair accessibility lifts, and light trailer ramp actuators.
Medical Equipment & Ergonomic Operating Tables: Delivers smooth, whisper-quiet hydraulic elevation and tilting fluid power for surgical tables, dental chairs, medical examination couches, and patient hoists.
Warehouse Electric Stackers & Light Pallet Trucks: Supplies compact, energy-efficient hydraulic lift power for mini electric stackers, manual-electric pallet lifters, and roll handlers.
Precision Industrial Clamping & Workholding Fixtures: Provides continuous high-pressure fluid hold for CNC machining center hydraulic vises, automatic workpiece clamp cylinders, and rotary indexer locks.
Lawn Mowers & Micro Agricultural Equipment: Powers cutter deck height adjustments, steering assist cylinders, and auxiliary hydraulic attachments on professional turf mowers and mini tractors.
| Key Specifications Overview
| Parameter | Hengyuhang HGP-1A Series Engineering Specification |
|---|---|
| Pump Architecture | High-Pressure External Micro Hydraulic Gear Pump for Hydraulic Power Units (HGP-1A Series) |
| Displacement Frame Ratings | 10 Standard Displacements: 0.5, 0.8, 1.0, 2.0, 2.6, 3.0, 4.0, 5.0, 6.0, and 7.8 cc/rev (mL/r) |
| Operational Rated Working Pressure | 210 kgf/cm² (21 MPa / 210 bar / 3,000 psi) for sizes 05~6; 170 kgf/cm² (17 MPa / 170 bar / 2,450 psi) for size 8 |
| Maximum Peak Operating Pressure | 250 kgf/cm² (25 MPa / 250 bar / 3,500 psi) for sizes 05~6; 210 kgf/cm² (21 MPa / 210 bar / 3,000 psi) for size 8 |
| Volumetric Efficiency Rating | ≥ 92% under rated pressure and speed with automatic pressure-balanced bush lobe clearance compensation |
| Rotational Speed Range | Rated: 1800 r.p.m. across all models; Maximum: 3200 to 4500 r.p.m.; Minimum: 600 to 1000 r.p.m. |
| Body & Housing Construction | High-tensile extruded aluminum alloy gear housing with rigid heavy-duty cast iron front and rear end covers |
| Gear & Shaft Engineering | One-piece integral drive and driven gear shafts manufactured from case-hardened high-purity alloy steel with precision-ground teeth |
| Bushing & Bearing System | Heavy-duty DU composite self-lubricating PTFE/bronze sleeve bushings providing high radial load capacity and minimal startup friction |
| Clearance Compensation Technology | Specialized bush lobe seals with elastomeric back-up rings providing automatic axial pressure balance to eliminate internal bypass slip |
| Mounting Flange Standards | 2B: SAE 2-bolt (pilot Ø50.8 mm); 4BE: European 4-bolt (pilot Ø30 mm); 4BDA: DIN 4-bolt Type A (pilot Ø25.4 mm); 4BDB: DIN 4-bolt Type B (pilot Ø30 mm) |
| Drive Shaft Configurations | Straight Keyed: X1 (Ø12.0 mm), X2 (Ø12.7 mm), X3 (Ø10.0 mm); Splined: Y1 (9T 20/40 DP), Y2 (15T 20/40 DP); Tapered: Z1 (1:8 taper, M7 × P1.0) |
| Fluid Port Configurations | Flange: Diamond F1 (30 mm pitch) / F2 (35 mm pitch); Threaded: G (BSPP G 3/8"~1/2"), P (PT 3/8"~1/2"), N (NPT 3/8"~1/2"), U (UNF 9/16" & 3/4") |
| Direction of Rotation | Clockwise (Code R, viewed facing shaft, standard/default) or Counter-Clockwise (Code L); Bi-directional hydraulic motor (Code M) optional |
| Unit Weight Range | Ultra-lightweight micro packaging: 1.00 kg (Size 05) to 1.40 kg (Size 8) |
| Hydraulic Fluid Compatibility | Premium anti-wear mineral hydraulic oils (ISO VG 32, 46, 68; DIN 51524 HLP); Viscosity range: 10 to 300 mm²/s (cSt); Temp: -15°C to +80°C |
| Fluid Cleanliness Standard | ISO 4406 Class 19/16 minimum (NAS 1638 Class 10; 25 μm suction filtration recommended to protect DU bushings and gear teeth) |
| Technical Performance Matrix Across Available Sizes
| Model Number | Accurate Displacement (cc/rev) | Operating Pressure (kgf/cm² / bar) | Rotational Speed (r.p.m.) | Theoretical Delivery Flow (L/min) | Unit Mass (kg, approx) | ||||
|---|---|---|---|---|---|---|---|---|---|
| Operational (Rated) | Max. Peak | Rated | Max. | Min. | @ 1500 r.p.m. | @ 1800 r.p.m. | |||
| HGP-1A-05 | 0.5 | 210 / 210 | 250 / 250 | 1800 | 4500 | 1000 | 0.75 | 0.90 | 1.00 |
| HGP-1A-08 | 0.8 | 210 / 210 | 250 / 250 | 1800 | 4500 | 1000 | 1.20 | 1.44 | 1.00 |
| HGP-1A-1 | 1.0 | 210 / 210 | 250 / 250 | 1800 | 4500 | 1000 | 1.50 | 1.80 | 1.00 |
| HGP-1A-2 | 2.0 | 210 / 210 | 250 / 250 | 1800 | 4500 | 600 | 3.00 | 3.60 | 1.05 |
| HGP-1A-26 | 2.6 | 210 / 210 | 250 / 250 | 1800 | 4500 | 600 | 3.90 | 4.68 | 1.15 |
| HGP-1A-3 | 3.0 | 210 / 210 | 250 / 250 | 1800 | 4500 | 600 | 4.50 | 5.40 | 1.15 |
| HGP-1A-4 | 4.0 | 210 / 210 | 250 / 250 | 1800 | 4000 | 600 | 6.00 | 7.20 | 1.18 |
| HGP-1A-5 | 5.0 | 210 / 210 | 250 / 250 | 1800 | 3200 | 600 | 7.50 | 9.00 | 1.20 |
| HGP-1A-6 | 6.0 | 210 / 210 | 250 / 250 | 1800 | 3200 | 600 | 9.00 | 10.80 | 1.30 |
| HGP-1A-8 | 7.8 | 170 / 170 | 210 / 210 | 1800 | 3200 | 600 | 11.70 | 14.04 | 1.40 |
| Mounting Flange Dimensional Standards (2B, 4BE, 4BDA/4BDB)
| Model Size | SAE 2-Bolt Flange (Code 2B) Pilot Ø50.8 mm / Bolt Spacing 82.55 mm | European 4-Bolt Flange (Code 4BE) Pilot Ø30.0 mm / Pattern 56.0 × 73.0 mm | DIN 4-Bolt Flange (Code 4BDA / 4BDB) Pilot Ø25.4 / Ø30.0 mm / Pattern 52.4 × 71.9 mm | |||
|---|---|---|---|---|---|---|
| Total Length A (mm) | Port Center B (mm) | Total Length A (mm) | Port Center B (mm) | Total Length A (mm) | Port Center B (mm) | |
| HGP-1A-08 | 67.5 | 32.5 | 75.5 | 32.5 | 67.5 | 32.5 |
| HGP-1A-1 | 69.5 | 33.5 | 77.5 | 33.5 | 69.5 | 33.5 |
| HGP-1A-2 | 72.0 | 34.8 | 80.1 | 34.8 | 72.0 | 34.8 |
| HGP-1A-3 | 77.5 | 37.5 | 85.5 | 37.5 | 77.5 | 37.5 |
| HGP-1A-4 | 79.5 | 38.5 | 87.5 | 38.5 | 79.5 | 38.5 |
| HGP-1A-5 | 83.5 | 40.5 | 91.5 | 40.5 | 82.5 | 40.5 |
| HGP-1A-6 | 87.5 | 42.5 | 95.5 | 42.5 | 87.5 | 42.5 |
| HGP-1A-8 | 93.5 | 45.5 | 101.5 | 45.5 | 93.5 | 45.5 |
| Drive Shaft and Fluid Port Configurations
| Configuration Group | Code & Type Designation | Engineering Specifications & Dimensional Standards |
|---|---|---|
| Straight Keyed Shafts (X) | X1 / X2 / X3 (Cylindrical with Woodruff Key) | X1: Ø12.0 mm (+0/-0.02) with 4 × 16 mm woodruff key (height 13.4 mm +0/-0.2); X2: Ø12.7 mm (+0/-0.02) with 3.175 × 19 mm key (height 14.0 mm +0/-0.2); X3: Ø10.0 mm (+0/-0.02) with 3 × 13 mm key (height 11.2 mm +0/-0.2). Usable shaft length: 25 mm; Extension: 28 mm (X1/X2) or 36 mm (X3). |
| Involute Splined Shafts (Y) | Y1 / Y2 (Involute Spline Teeth) | Y1: 9-Tooth (9T × 20/40 DP × 30° pressure angle, extension 27.7 mm, effective spline length 14.4 mm); Y2: 15-Tooth (15T × 20/40 DP × 30° pressure angle, extension 22.0 mm, effective spline length 11.9 mm). Direct spline coupling for zero backlash. |
| Tapered Shaft (Z) | Code Z1 (1:8 Taper with Retaining Nut) | 1:8 conical taper with M7 × P1.0 threaded shaft end (8 mm thread length); Usable shaft length: 25 mm; Total extension: 28 mm; Drive key: 2.4 × 5.5 mm woodruff key; Major taper diameter: Ø12.3 mm. Zero-backlash conical friction locking. |
| Diamond Flange Ports (F) | Code F1 / F2 (Metric Flange Type) | Code F1: Inlet 30 mm bolt pitch / Ø14.50 mm bore (M6), Outlet 30 mm pitch / Ø14.50 mm bore (M6); Code F2: Inlet 35 mm bolt pitch / Ø14.50 mm bore (M6), Outlet 35 mm pitch / Ø14.50 mm bore (M6). O-ring sealed flange connection. |
| Threaded Fluid Ports (G, P, N, U) | BSPP (G), PT (P), NPT (N), UNF (U) | G1: Inlet G 3/8", Outlet G 3/8"; G2: Inlet G 1/2", Outlet G 3/8"; P1: 3/8" PT / 3/8" PT (sizes 08~6); P2: 1/2" PT / 3/8" PT (size 8); N1/N2: NPT equivalents; U1: Inlet 9/16"-18UNF / Outlet 9/16"-18UNF; U2: Inlet 3/4"-16UNF / Outlet 9/16"-18UNF. |
| Model Coding & Ordering Information
| Code Position | Code Designation | Available Standard Options | Technical Definition & Description |
|---|---|---|---|
| [1] Model Series | Product Series | HGP-1A | External Hydraulic Power Unit Micro Gear Pump Series (0.5 to 7.8 cc/rev) |
| [2] Mounting Style | Mounting Configuration | F / L | Code F: Flange Mounting Type (Standard); Code L: Foot Bracket Mounting Type |
| [3] Delivery Capacity | Displacement Size (cc/rev) | 05, 08, 1, 2, 26, 3, 4, 5, 6, 8 | Geometric displacement rating: 0.5 up to 7.8 cc/rev (Sizes 05 and 26 are customizable options) |
| [4] Rotation Direction | Direction of Shaft Rotation | R / L / M | Code R: Clockwise Rotation (viewed facing shaft, standard); Code L: Counter-Clockwise Rotation; Code M: Bi-directional Hydraulic Motor |
| [5] Drive Shaft Type | Input Shaft Configuration | X1~X3 / Y1~Y2 / Z1 | Code X: Straight cylindrical keyed shaft; Code Y: Involute splined shaft; Code Z: Tapered shaft with retaining nut |
| [6] Mounting Flange Type | Flange Pattern Standard | 2B / 4BDA / 4BDB / 4BE | Code 2B: SAE 2-bolt (pilot Ø50.8 mm); Code 4BDA: DIN 4-bolt Type A (pilot Ø25.4 mm); Code 4BDB: DIN 4-bolt Type B (pilot Ø30 mm); Code 4BE: European 4-bolt (pilot Ø30 mm) |
| [7] Fluid Port Connections | Inlet & Outlet Port Types | F (F1~F2) / G (G1~G2) / P (P1~P2) / N (N1~N2) / U (U1~U2) | Code F: Flange type (F1~F2); Code G: BSPP (PF); Code P: PT (BSPT); Code N: NPT thread; Code U: SAE O-ring boss UNF thread |
| Technical Performance Matrix Across Available Sizes
| Model Number | Accurate Displacement (cc/rev) | Operating Pressure (kgf/cm² / bar) | Rotational Speed (r.p.m.) | Theoretical Delivery Flow (L/min) | Unit Mass (kg, approx) | ||||
|---|---|---|---|---|---|---|---|---|---|
| Operational (Rated) | Max. Peak | Rated | Max. | Min. | @ 1500 r.p.m. | @ 1800 r.p.m. | |||
| HGP-1A-05 | 0.5 | 210 / 210 | 250 / 250 | 1800 | 4500 | 1000 | 0.75 | 0.90 | 1.00 |
| HGP-1A-08 | 0.8 | 210 / 210 | 250 / 250 | 1800 | 4500 | 1000 | 1.20 | 1.44 | 1.00 |
| HGP-1A-1 | 1.0 | 210 / 210 | 250 / 250 | 1800 | 4500 | 1000 | 1.50 | 1.80 | 1.00 |
| HGP-1A-2 | 2.0 | 210 / 210 | 250 / 250 | 1800 | 4500 | 600 | 3.00 | 3.60 | 1.05 |
| HGP-1A-26 | 2.6 | 210 / 210 | 250 / 250 | 1800 | 4500 | 600 | 3.90 | 4.68 | 1.15 |
| HGP-1A-3 | 3.0 | 210 / 210 | 250 / 250 | 1800 | 4500 | 600 | 4.50 | 5.40 | 1.15 |
| HGP-1A-4 | 4.0 | 210 / 210 | 250 / 250 | 1800 | 4000 | 600 | 6.00 | 7.20 | 1.18 |
| HGP-1A-5 | 5.0 | 210 / 210 | 250 / 250 | 1800 | 3200 | 600 | 7.50 | 9.00 | 1.20 |
| HGP-1A-6 | 6.0 | 210 / 210 | 250 / 250 | 1800 | 3200 | 600 | 9.00 | 10.80 | 1.30 |
| HGP-1A-8 | 7.8 | 170 / 170 | 210 / 210 | 1800 | 3200 | 600 | 11.70 | 14.04 | 1.40 |
| Model Size | SAE 2-Bolt Flange (Code 2B) Pilot Ø50.8 mm / Bolt Spacing 82.55 mm | European 4-Bolt Flange (Code 4BE) Pilot Ø30.0 mm / Pattern 56.0 × 73.0 mm | DIN 4-Bolt Flange (Code 4BDA / 4BDB) Pilot Ø25.4 / Ø30.0 mm / Pattern 52.4 × 71.9 mm | |||
|---|---|---|---|---|---|---|
| Total Length A (mm) | Port Center B (mm) | Total Length A (mm) | Port Center B (mm) | Total Length A (mm) | Port Center B (mm) | |
| HGP-1A-08 | 67.5 | 32.5 | 75.5 | 32.5 | 67.5 | 32.5 |
| HGP-1A-1 | 69.5 | 33.5 | 77.5 | 33.5 | 69.5 | 33.5 |
| HGP-1A-2 | 72.0 | 34.8 | 80.1 | 34.8 | 72.0 | 34.8 |
| HGP-1A-3 | 77.5 | 37.5 | 85.5 | 37.5 | 77.5 | 37.5 |
| HGP-1A-4 | 79.5 | 38.5 | 87.5 | 38.5 | 79.5 | 38.5 |
| HGP-1A-5 | 83.5 | 40.5 | 91.5 | 40.5 | 82.5 | 40.5 |
| HGP-1A-6 | 87.5 | 42.5 | 95.5 | 42.5 | 87.5 | 42.5 |
| HGP-1A-8 | 93.5 | 45.5 | 101.5 | 45.5 | 93.5 | 45.5 |
WhatsApp
Email
+86 19918575358
