Spare Parts & Rotary Group Repair Kits for Bosch Rexroth A4VG Series Hydraulic Piston Pumps

Key Specifications

Overview

HYLINK supplies precision-engineered Bosch Rexroth A4VG series (A4VG28 through A4VG500) swashplate-design variable displacement axial piston pump replacement parts and complete rotary group overhaul kits. Specially engineered for high-pressure closed-circuit hydrostatic transmissions, every component is manufactured to exact original dimensions and tolerances to ensure seamless fitment and dependable performance.

Product Overview

Bosch Rexroth A4VG series variable axial piston pumps serve as main power generators in heavy-duty closed-circuit hydrostatic drive systems. Operating under continuous high working pressures, reversing fluid flows, and severe torque fluctuations, internal rotating assemblies—including the drive shaft, cylinder block, pistons with slipper shoes, swashplate, spherical hinge springs, and valve plate—experience constant sliding friction and mechanical stress. Surface wear on these critical contact interfaces causes internal fluid bypass leakage, thermal elevation, displacement output loss, and reduced system drive response.

HYLINK manufactures high-precision replacement rotary groups and individual pump spare parts across the complete A4VG displacement range (28 to 500 cm³/rev). Produced from premium forged alloy steel and high-wear-resistant bronze formulations, each part undergoes micron-level CNC machining and 3D CMM quality verification. This enables hydraulic repair specialists and equipment rebuilders to cost-effectively overhaul worn pump core assemblies and restore original volumetric efficiency without purchasing expensive outer pump housing structures.

Available Components

Below is the standardized component list for Bosch Rexroth A4VG series hydraulic pumps. Individual spare parts and complete rotary group repair kits are both available:

Quality Assurance & Manufacturing

Every HYLINK pump and replacement part undergoes strict quality control before shipment:

l Dimensional accuracy — checked with high-precision CMM (Coordinate Measuring Machines) to guarantee an exact fit with original pump housings.

l Material metallurgy — manufactured from premium forged steel and high-wear-resistant alloys to prevent premature fatigue.

l 100% performance test — every complete pump assembly is tested on our dynamic hydraulic test rig for pressure, flow rate and efficiency under full working load.

Packing, Shipping & Warranty

l Packaging — anti-rust protective film + heavy-duty foam cushioning + standard export fumigation-free wooden case (reinforced carton for small spare parts).

l Shipping — express courier (DHL / FedEx) for urgent repair orders; sea or air cargo for bulk orders.

l Warranty — 6 months quality assurance against manufacturing and material defects from the delivery date. In the event of a confirmed quality defect, HYLINK provides hassle-free replacement.

FAQ

Q: Are your SBS pump parts interchangeable with genuine Caterpillar parts?

A: Yes. All parts are produced to original specifications and dimensions and are 100% interchangeable — no modification is required during installation.

Q: What is the minimum order quantity?

A: 1 piece. We supply both individual components and complete rotary group / repair kits.

Q: How fast can you ship?

A: In-stock items are dispatched within 1–3 days; standard production orders take 5–8 days. Express and sea/air freight are both available.

Q: How do I confirm the correct part for my machine?

A: Send us your excavator model, pump model (SBS80 / SBS120 / SBS140) and the part name or photo — our technical team will confirm the correct item before you order.

Q: What warranty do you offer?

A: 6 months against manufacturing and material defects, with replacement support for confirmed quality issues.