Rexroth A20VO / A20VLO Axial Piston Variable Double Pump: The Ultimate Guide to Twin-Rotor Hydraulic Power, OEM Replacements, and Spare Parts for Ultra-Heavy Machinery in 2026

Author: Elephant Fluid Power Co., Ltd. | Updated: July 14, 2026 | Reading Time: 22 minutes

Quick Answer: If you operate ultra-large excavators, mining shovels, heavy cranes, drilling rigs, or multi-circuit hydraulic systems that require massive flow capacity from a single compact pump unit, the Rexroth A20VO / A20VLO axial piston variable double pump is the engineering solution. Featuring two independent rotary groups arranged back-to-back in one housing, the A20VO delivers total flow up to 1,508 L/min and torque up to 5,793 N·m at 350 bar nominal / 400 bar peak pressure — equivalent to two conventional pumps in 40% less installation space. Elephant Fluid Power Co., Ltd. manufactures complete A20VO and A20VLO double pumps (sizes 60, 95, 190, 260, 520) and over 1,300 types of 100% interchangeable spare parts — cylinder blocks, piston shoes, valve plates, swash plates, retainer plates, drive shafts, control valves, and seal kits — delivering OEM-equivalent performance at 50-75% lower cost with same-day shipping from stock. With nearly 20 years of manufacturing excellence, German CNC production equipment, and distribution to 80+ countries, Elephant Fluid Power provides the fair pricing, fine quality, fast delivery, and world-class service that heavy machinery operators worldwide depend on.

1. What Is the Rexroth A20VO / A20VLO Double Pump?

The Rexroth A20VO and A20VLO represent one of the most innovative and powerful hydraulic pump designs ever engineered for open-circuit hydrostatic drives. Unlike conventional single-rotor axial piston pumps, the A20VO is a variable displacement double pump incorporating two complete axial piston rotary groups arranged in a back-to-back (tandem) configuration within a single pump housing. This unique architecture delivers the combined flow output of two independent pumps — each with its own service port (Port A and Port B) — while sharing a common suction port (Port S) and occupying significantly less physical space than two separate pumps mounted side by side.

The operating principle leverages the proven swashplate technology found in Rexroth’s A11VO, A10VO/53, and A4VSO series. Each rotary group contains a cylindrical barrel with 9 precision pistons that reciprocate against an angled swashplate as the barrel rotates. The swashplate angle is hydraulically adjustable in each rotary group independently, enabling infinitely variable flow control from zero to maximum displacement for each service circuit. This means the A20VO can simultaneously power two separate hydraulic circuits — for example, travel drives on one port and implement functions on the other — with independent flow regulation for each circuit.

1.1 The Revolutionary Back-to-Back Design: Five Engineering Breakthroughs

The A20VO’s twin-rotor architecture delivers five transformative advantages that have made it the preferred power source for the world’s most demanding hydraulic machinery. First and most importantly, the double-pump design delivers total flow equal to two conventional pumps from a single compact housing — the A20VO 520 produces 1,508 L/min total flow (754 L/min per rotary group), which would otherwise require two separate pumps each weighing 300+ kg. This space-saving architecture reduces overall machine envelope by approximately 40% compared to dual-pump installations, freeing valuable space for other components or enabling more compact machine designs. Second, the single suction port simplifies hydraulic plumbing dramatically — instead of two separate suction lines, filters, and reservoirs, the A20VO requires only one inlet connection that feeds both rotary groups internally. This reduces hose count, eliminates potential leak points, and lowers installation cost. Third, the back-to-back arrangement provides inherent mechanical balance — the axial thrust forces generated by each rotary group act in opposing directions, substantially reducing the net thrust load on the main bearings and extending bearing life compared to single-rotor pumps of equivalent capacity. Fourth, the common through-drive capability on the rear of the pump allows additional gear pumps or axial piston pumps to be mounted, creating multi-pump installations with up to three or four hydraulic circuits powered by a single prime mover. Fifth, the pump uses proven components from Rexroth’s established A11VO (for sizes 95, 190, 260), A10VO/53 (for size 60), and A4VSO (for size 520) series — ensuring that spare parts availability, service knowledge, and aftermarket support leverage an existing global infrastructure of millions of installed pumps.

1.2 A20VO vs. A20VLO: The Charge Pump Distinction

Within the A20V family, the critical distinction is the presence or absence of an integrated charge pump (impeller):

The A20VLO 190 and 260 are the dominant specifications for ultra-large mining excavators operating at high altitude or in Arctic conditions where inlet pressure conditions are challenging. The integrated centrifugal impeller actively fills the pump housing with hydraulic fluid, preventing cavitation and enabling reliable operation under the most demanding suction conditions.

1.3 The Ultra-Heavy-Duty Aftermarket: Why A20VO Replacement Demand Is Surging

The global market for A20VO double pump replacements and spare parts is experiencing strong growth driven by several converging factors. The installed base of ultra-large excavators and mining equipment using A20VO pumps has expanded significantly over the past decade, with major manufacturers including Caterpillar, Komatsu, Hitachi, Liebherr, and Hyundai specifying A20VO 190/260 pumps on their largest models. OEM pricing for a complete A20VO 260 double pump can exceed $8,000-12,000 USD, with individual spare parts like cylinder blocks ($600-1,000 per rotary group), piston shoe sets ($400-700 per set of 9), and valve plates ($300-500 each) commanding substantial premiums. Lead times from European OEM distribution centers frequently extend to 12-20 weeks for complete pumps and 8-12 weeks for major spare parts — unacceptable timelines for equipment generating $10,000-30,000 per day in production value.

This cost-availability gap has created massive demand for high-quality compatible alternatives. Equipment fleet operators, mining contractors, and heavy machinery rebuilders are actively seeking suppliers capable of delivering Rexroth-interchangeable A20VO pumps and parts at competitive prices with responsive global delivery.

2. Complete A20VO / A20VLO Technical Specifications: All Five Sizes

The A20VO series is available in five displacement sizes — 60, 95, 190, 260, and 520 cm³ per rotary group. Because each pump contains two rotary groups, the total flow output is double the per-group flow. The following tables provide comprehensive technical data for accurate pump specification.

2.1 A20VO 60 — Compact Double Pump Entry Model

The A20VO 60 is the smallest double pump in the series, featuring rotary groups based on A10VO/53 technology. With a nominal pressure of 250 bar (315 bar peak), this size serves medium-duty multi-circuit applications where moderate pressure and flow are required from a compact twin-pump package.

2.2 A20VO 95 — Medium-Heavy-Duty Double Pump

The A20VO 95 steps up to 350 bar nominal pressure (400 bar peak) with rotary groups based on A11VO technology. This size delivers 440 L/min total flow and is commonly found on large excavators (30-50 ton) requiring independent travel and implement circuits.

2.3 A20VO 190 / A20VLO 190 — Large Excavator and Mining Standard

The A20VO 190 and A20VLO 190 represent the workhorse double pump for 50-100 ton hydraulic excavators and medium mining equipment. The A20VLO 190 variant with integrated charge pump is the dominant specification for mining excavators operating at altitude.

2.4 A20VO 260 / A20VLO 260 — Ultra-Large Mining Powerhouse

The A20VO 260 and A20VLO 260 are the second-largest double pumps in the series, delivering 1,196 L/min total flow and 698 kW power output. These pumps power 100-300 ton mining excavators and the largest hydraulic shovels.

2.5 A20VO 520 — The Absolute Maximum Flow Monster

The A20VO 520 is the largest double pump in the Rexroth lineup, using rotary groups based on A4VSO technology. With 520 cm³ per rotary group and total flow of 1,508 L/min, this pump represents the pinnacle of open-circuit hydraulic power density.

2.6 Complete A20VO Series Comparison Summary

3. Five Game-Changing Advantages of the A20VO Double Pump Design

The A20VO’s twin-rotor architecture is not merely an incremental improvement over single-pump designs — it represents a fundamental paradigm shift in how hydraulic power is delivered to heavy machinery. Understanding these advantages is essential for engineers, procurement managers, and equipment operators evaluating pump options for new builds or replacement scenarios.

3.1 Advantage One: One Pump Equals Two Pumps — Double the Flow, Single Housing

The most compelling benefit of the A20VO is its flow density. A single A20VO 260 produces 1,196 L/min total flow — the equivalent of two A11VO 260 pumps (598 L/min each) operating in parallel. Yet the A20VO 260 occupies approximately 40% less installation space than two separate A11VO pumps with their individual mounting brackets, coupling assemblies, and plumbing connections. For machine designers, this means more compact machine envelopes, reduced structural framing requirements, and greater flexibility in component layout. For equipment rebuilders, it means simplified retrofits — replacing two aging pumps with one A20VO eliminates alignment issues, reduces coupling wear points, and simplifies maintenance access.

3.2 Advantage Two: One Suction Feeds Two Services — Simplified Plumbing, Lower Cost

Conventional dual-pump installations require two separate suction lines, each with its own filter, hose assembly, and reservoir connection. The A20VO’s single suction port feeds both rotary groups through internal passages, reducing the external plumbing to one suction line, one return line, and two service lines (A and B). This simplification delivers multiple cost savings: reduced hose inventory (fewer hoses, fewer fittings), lower installation labor, elimination of one suction filter, reduced potential leak points, and cleaner hydraulic schematic drawings that are easier to troubleshoot.

3.3 Advantage Three: Back-to-Back Mechanical Balance — Extended Bearing Life

In a single-rotor axial piston pump, the axial thrust force generated by the pressurized pistons pushes the rotating assembly against the main thrust bearing, creating significant bearing loads that limit pump life. The A20VO’s back-to-back arrangement positions the two rotary groups so their thrust forces act in opposite directions, partially canceling each other out. This thrust balancing effect substantially reduces the net load on the main bearings, enabling higher pressure operation, longer bearing life, and reduced maintenance frequency compared to single-rotor pumps of equivalent total capacity.

3.4 Advantage Four: Multi-Circuit System Ready — Travel + Implement from One Pump

The A20VO’s two independent service ports make it the ideal power source for multi-circuit hydraulic systems. On a large hydraulic excavator, for example, Port A can supply the travel drive circuit while Port B supplies the boom/arm/bucket implement circuit — each with independent flow control via its own swashplate angle adjustment. This eliminates the need for external flow dividers or priority valves that add cost, complexity, and pressure loss to the hydraulic system. The control valves for each rotary group operate independently, enabling sophisticated hydraulic strategies such as power priority (directing more flow to the implement circuit during digging) or travel priority (ensuring consistent travel speed during combined operations).

3.5 Advantage Five: Through-Drive Expandable — Three or Four Circuits from One Engine

The A20VO retains the 100% through-drive capability of its single-rotor siblings, allowing additional pumps to be mounted on the rear flange. A typical large excavator configuration might use: A20VO 260 (main pump, travel + implement) + A10VO 45 gear pump (pilot/control circuit) + A10VO 28 charge pump (cooling fan). This three-pump stack delivers three independent hydraulic circuits from a single diesel engine through a single pump mounting pad — an elegant solution that minimizes engine PTO complexity while maximizing hydraulic flexibility.

4. Control Device Selection for A20VO Double Pumps

The A20VO’s control options vary by pump size, with each size family adopting the control architecture of its underlying technology base. The following table maps control types to A20VO sizes and applications.

Control Code Definitions:

• LR = Power control (constant kW limitation)

• LRD = Power control + Pressure cut-off

• LRDS = Power + Pressure cut-off + Load sensing (most common for excavators)

• LR.C = 2-stage power control (switchable)

• LR3 = 3-stage power control

• LG1/LG2 = Hydraulic on/off power switching

• DR = Pressure control

• DRS = Pressure control + Load sensing

• EP = Electronic proportional control

• HD = Hydraulic pilot control

• LR2DN/LR3DN = A4VSO-style multi-stage power controls

5. Application Guide: Where A20VO Double Pumps Dominate

5.1 Ultra-Large Hydraulic Excavators (50-300+ Ton Class)

The A20VO series is the dominant main pump platform for the largest hydraulic excavators in the world. The independent dual-circuit capability — travel on one port, implement on the other — is ideally suited to excavator hydraulic architecture.

5.2 Mining Shovels and Draglines

For electric rope shovels converted to hydraulic drive and large hydraulic mining shovels, the A20VO 520 delivers the massive flow and torque required for bucket filling, hoisting, and crowd operations.

5.3 Heavy Cranes and Lifting Equipment

Large crawler cranes, floating cranes, and heavy-lift vessels use A20VO pumps for hoist, luff, and slew circuits requiring synchronized multi-axis control.

5.4 Drilling Rigs and Piling Equipment

Large rotary drilling rigs for foundation work and offshore drilling platforms use A20VO pumps for rotation, feed, and auxiliary hydraulic functions.

5.5 Marine and Industrial Applications

6. Complete A20VO Spare Parts Program: 100% Interchangeable with Original Rexroth

When an A20VO pump fails on a $2 million mining excavator, every hour of downtime costs $10,000-30,000. Elephant Fluid Power’s comprehensive spare parts program addresses this critical need by manufacturing over 1,300 types of hydraulic pump spare parts with 100% dimensional and functional interchangeability — including the unique double-pump components specific to the A20VO architecture.

6.1 Core Spare Parts for A20VO / A20VLO Series

Because the A20VO contains two complete rotary groups plus shared housing components, its spare parts program is more extensive than single-pump designs. All parts are manufactured using German CNC equipment, premium non-ferrous metal raw materials, and strict quality inspection standards.

6.2 Cost Comparison: OEM Rexroth vs. Elephant Fluid Power A20VO Parts

6.3 Quality Assurance and Manufacturing Process

Elephant Fluid Power’s A20VO spare parts manufacturing follows a rigorous multi-stage protocol:

1. Material Verification: Spectrographic analysis confirms alloy composition meets OEM specifications

2. CNC Machining: German CNC centers maintain ±0.003mm tolerance on critical surfaces

3. Heat Treatment: Vacuum hardening achieves 58-62 HRC with controlled case depth

4. Precision Finishing: Grinding/honing achieves Ra 0.1-0.2 μm on sealing surfaces

5. 100% Dimensional Inspection: CMM verification against OEM drawings

6. Assembly & Pressure Testing: Each rotary group tested at 1.5× rated pressure (525-600 bar) for 3 minutes

7. Performance Validation: Flow, pressure, and efficiency curves verified within ±2% of OEM data

7. Why Elephant Fluid Power? Fair Pricing, Fine Quality, Fast Delivery, World-Class Service

7.1 Fair Pricing: Delivering Value Without Compromise

Elephant Fluid Power’s pricing reflects manufacturing efficiency, not brand markup. Located in Shijiazhuang, Hebei Province — China’s advanced manufacturing corridor — the company leverages a mature supply chain ecosystem that eliminates the multi-layer distribution markups inflating OEM prices by 200-300%. The company uses the same grade of materials as Rexroth, operates German CNC machining centers meeting identical precision standards, and employs comparable quality protocols — achieving cost savings through structural advantages, not quality compromises. For a mining contractor operating 3 ultra-large excavators with A20VO 260 pumps, switching to Elephant Fluid Power for annual maintenance yields $80,000-120,000 in parts cost savings per year.

7.2 Fine Quality: German CNC, Premium Materials, Zero-Defect Standards

The manufacturing facility features DMG MORI and GROB German CNC machining centers, Coordinate Measuring Machines (CMM) for 100% critical dimension verification, hydraulic test benches to 600 bar, dynamometer testing for performance curve validation, and a material laboratory for metallurgical analysis. Every A20VO pump and part undergoes documented quality control at multiple stages, resulting in consistent quality that has earned repeat business from 80+ countries.

7.3 Fast Delivery: Same-Day Shipping for Critical Repairs

7.4 Service That Serves the World

Elephant Fluid Power provides pump selection assistance, troubleshooting support, model identification from damaged nameplates, technical documentation, 12-month warranty, and custom engineering for unique applications. Customer testimonials consistently highlight responsiveness, technical competence, and genuine commitment to customer success:

“Very satisfied, good quality, fast delivery, saving a lot of costs for my pump.” — Martin, Europe

“Wow, it’s perfect. They sent the right accessories to me, and the installation is completely suitable.” — Filippo, Italy

8. How to Order: A20VO Pump and Parts Procurement Guide

8.1 Decoding the Rexroth A20VO Model Number

Common model numbers:

• A20VO190DRS/10R-NZD24N00 — Standard large excavator double pump

• A20VLO190DRS/10R-NZD24N00 — A20VLO variant with charge pump

• A20VO260LRDS/10R-NZD24N00 — Ultra-large mining excavator

• A20VO95DRS/10R-NSD24N00 — Medium-large excavator

• A20VO520LR3DN/10R-VZH26K99 — Giant mining equipment

If your nameplate is missing, provide equipment make/model and photos of the pump. Elephant Fluid Power engineers can cross-reference to identify the correct replacement.

8.2 Ordering Process

Send pump model number or part description to elephant@sjzhjsm.com or WhatsApp +86-180-3112-1586. Engineering confirmation and quotation provided within 24 hours. Payment via T/T, L/C, Western Union, or PayPal. Shipping via DHL/FedEx/UPS express or sea freight.

9. Frequently Asked Questions: A20VO Double Pumps and Parts

Q1: What makes the A20VO different from installing two separate pumps?

The A20VO integrates two rotary groups in one housing with a single suction port and two independent service ports. Compared to two separate pumps, the A20VO saves ~40% installation space, reduces plumbing by 50% (one suction line instead of two), provides inherent thrust balancing for longer bearing life, and eliminates the need for external flow dividers in multi-circuit systems. Maintenance is simplified because both rotary groups share common housing components and are accessible from a single pump location.

Q2: What is the best replacement for a Rexroth A20VO double pump?

Elephant Fluid Power manufactures complete A20VO and A20VLO double pumps in all sizes (60, 95, 190, 260, 520) with 100% dimensional interchangeability and identical performance characteristics to original Rexroth pumps. All pumps are assembled using German CNC-machined components, premium raw materials, and undergo 1.5× pressure testing before shipment. Buyers receive OEM-equivalent performance at 50-75% lower cost with delivery times of 2-4 weeks compared to 12-20 weeks for original Rexroth pumps.

Q3: How much can I save by buying A20VO parts from Elephant Fluid Power?

Complete A20VO pumps cost 60-70% less than original Rexroth — an A20VO 190 is approximately $1,500-2,500 from Elephant Fluid Power versus $4,000-6,500 from Rexroth. An A20VO 260 costs $2,200-3,500 versus $6,000-10,000 OEM. Spare parts offer 65-75% savings — a rotating group costs $450-750 versus $1,500-2,500 OEM. For a mining contractor with 3 ultra-large excavators, annual maintenance savings exceed $80,000-120,000.

Q4: When should I choose A20VLO instead of A20VO?

Choose A20VLO (with charge pump) for applications with challenging inlet conditions: high-altitude operation (above 2,500m), extreme cold climates, or where self-priming capability is required. The A20VLO 190 and 260 are the industry standard for large mining excavators operating in these conditions. Choose A20VO for standard heavy equipment with positive inlet pressure (flooded suction or external boost pump).

Q5: Which A20VO size do I need for my excavator?

• 30-50 ton excavators: A20VO 95 (440 L/min total)

• 50-100 ton excavators: A20VO 190 / A20VLO 190 (964 L/min total)

• 100-300 ton mining excavators: A20VO 260 / A20VLO 260 (1,196 L/min total)

• 300+ ton giant mining shovels: A20VO 520 (1,508 L/min total)

• A20VO 60: Medium-duty multi-circuit industrial systems (324 L/min total)

Q6: Does Elephant Fluid Power supply complete A20VO pumps or only parts?

Both. Elephant Fluid Power supplies: complete A20VO and A20VLO double pumps (all 5 sizes, all control types), complete rotating groups (pre-assembled per rotary group), individual spare parts for both rotary groups and shared housing components, charge pumps (for A20VLO variants), control valve modules, seal kits, and pump repair/rebuild kits. All complete pumps are fully assembled, pressure-tested, and ready for installation.

Q7: What is the warranty on Elephant Fluid Power A20VO pumps and parts?

Elephant Fluid Power provides a 12-month warranty from the date of shipment against defects in materials and workmanship. The warranty covers free replacement of defective components upon return of the failed part for failure analysis. Pumps and parts must be operated within published specifications for warranty coverage.

Q8: Can Elephant Fluid Power supply parts for other pump brands?

Yes. Beyond the A20VO/A20VLO series, Elephant Fluid Power manufactures compatible spare parts for Rexroth (A10VSO, A10VO, A11VO, A4VG, A4VSO, A2FO, A7VO, A6VM), Eaton/Vickers (PVH, PVE, 46/54/64 series), Parker (PVP, PAVC, F11/F12), Kawasaki (K3V, K5V, K7V), Komatsu (HPV, HPF), Sauer/Danfoss (90R, 90M), Linde (HPR, HMF), Liebherr (LPVD, LMF), Yuken (A series), and Uchida (AP2D, A10 series). Over 1,300 types of spare parts in total.

Q9: What spare parts are most commonly replaced on A20VO pumps?

The most frequently replaced A20VO components are: rotating groups (cylinder block + pistons + valve plate + retainer plate — typically replaced as a matched set when wear exceeds tolerance), seal kits (shaft seals, O-rings, and gaskets — recommended at every major service interval), control valve modules (when control response degrades or external leakage occurs), charge pumps (A20VLO variants — impeller wear from contaminated fluid), and drive shafts (when spline wear or torsional damage is detected). A complete pump rebuild typically requires two rotating groups (one per rotary group), one shared seal kit, and inspection of the drive shaft and housing.

Q10: How do I contact Elephant Fluid Power for an A20VO quotation?

Contact Information:

• Website: www.hydpumpparts.com

• Email: elephant@sjzhjsm.com

• Phone/WhatsApp: +86-180-3112-1586

• Office Phone: +86-311-6812-3061

• Address: No.398 Youyi Street, Xinhua District, Shijiazhuang City, Hebei, China

• Business Hours: 8:30-18:00 Beijing Time (UTC+8)

For fastest response, include your pump model number (or equipment make/model), required parts description, quantity, and destination country. Quotations within 24 hours.

10. Conclusion: The Future of Heavy-Duty Hydraulic Power Is Double

The Rexroth A20VO / A20VLO axial piston variable double pump represents a paradigm shift in hydraulic power delivery for the world’s most demanding machinery. By integrating two independent rotary groups in a single back-to-back housing, the A20VO delivers unprecedented flow density, simplified system architecture, inherent mechanical balance, and multi-circuit capability that single-pump designs simply cannot match. From 50-ton hydraulic excavators to 800-ton mining shovels, from heavy-lift cranes to offshore drilling platforms, the A20VO series provides the reliable, efficient, and compact hydraulic power that keeps ultra-heavy industry moving.

When these pumps require replacement or repair, Elephant Fluid Power Co., Ltd. stands ready as your trusted global partner — delivering complete A20VO and A20VLO double pumps and over 1,300 types of 100% interchangeable spare parts with OEM-equivalent performance at 50-75% lower cost. With nearly 20 years of manufacturing excellence, German CNC production equipment, distribution to 80+ countries, and an unwavering commitment to fair pricing, fine quality, fast delivery, and world-class service, Elephant Fluid Power has earned its position as a leader in the heavy-duty hydraulic aftermarket.

Ready to request your A20VO quotation? Visit www.hydpumpparts.com or contact elephant@sjzhjsm.com with your pump model number or part requirements. Our technical team will provide specification confirmation, competitive pricing, and delivery options within 24 hours.

About Elephant Fluid Power Co., Ltd.

Established in Shijiazhuang, Hebei Province, China, Elephant Fluid Power Co., Ltd. is a professional manufacturer and global supplier of hydraulic piston pumps, hydraulic motors, pump spare parts, and hydraulic components. With nearly 20 years of experience, the company produces Rexroth-compatible A20VO, A20VLO, A11VO, A10VSO, A10VO, A4VG, A4VSO, A2FO, and A7VO series pumps, along with over 1,300 types of 100% interchangeable spare parts. Elephant Fluid Power serves customers in 80+ countries across ultra-large excavators, mining equipment, heavy cranes, drilling rigs, marine systems, and heavy industrial applications. Our mission: fair pricing, fine quality, fast delivery, and service that serves people worldwide.

Contact Information:

• Website: www.hydpumpparts.com

• Email: elephant@sjzhjsm.com

• Phone/WhatsApp: +86-180-3112-1586

• Office: +86-311-6812-3061

• Address: No.398 Youyi Street, Xinhua District, Shijiazhuang City, Hebei, China