ABB IRB 4600 Gearbox Modules: 3HAC028837-008 / 3HAC028837-006

Technical Dossier

Product Details And Specifications

ABB IRB 4600 Series: Comprehensive Gearbox Module Range and Technical Overview

The ABB IRB 4600 is a medium-payload industrial robot platform deployed across automotive body-in-white assembly, arc welding, material handling, and machine tending applications in facilities ranging from tier-1 automotive suppliers to heavy fabrication plants. Its gearbox subsystem — particularly the axis-1 through axis-6 reduction units — represents one of the highest-frequency spare part categories in ABB robot maintenance programs globally. The TS245RHS i=125 gearbox (3HAC028837-008 / 3HAC028837-006) is the axis-1 primary reduction unit, a precision cycloidal or harmonic-type gearbox responsible for base rotation torque transmission. Unplanned failure of this component results in full robot downtime, making proactive inventory management a direct operational cost variable.

The Evolution of IRB 4600 Gearbox Architecture

The IRB 4600 platform was introduced by ABB Robotics (Sweden) in the early 2010s as a successor to the IRB 4400 series, targeting a payload range of 20–60 kg with a reach envelope of 2.05–2.55 m. The gearbox architecture across the IRB 4600 family uses sealed, grease-lubricated reduction units with integrated output flanges, designed for minimal field maintenance. Early production units (pre-2015) used gearbox assemblies with part suffix -001 through -004; revised assemblies introduced from 2015 onward carry suffixes -006, -007, and -008, reflecting updated sealing compounds, revised bearing preload specifications, and compatibility with IRC5 controller firmware revisions. The -008 revision (3HAC028837-008) is the current production standard and is backward-compatible with earlier IRB 4600 mechanical variants. Procurement teams sourcing replacement units must verify the axis designation, gear ratio (i=125 for axis 1), and flange pattern (FP = flat pattern) to avoid fitment errors. Cross-referencing with the robot's serial number and mechanical revision label is mandatory before ordering.

IRB 4600 Full Catalog & Functionalities (SKU List)

The following SKUs represent the primary gearbox, motor, and mechanical spare part range for the ABB IRB 4600 robot family. All units listed are confirmed part numbers within the ABB 3HAC spare parts catalog.

Axis Gearbox Units:

• 3HAC028837-008: Axis-1 gearbox assembly, TS245RHS, i=125, flat flange pattern — current production revision
• 3HAC028837-006: Axis-1 gearbox assembly, TS245RHS, i=125 — prior production revision, functionally equivalent to -008
• 3HAC028837-007: Axis-1 gearbox assembly, intermediate revision, compatible with IRB 4600-20/2.50 and 4600-40/2.55
• 3HAC029157-001: Axis-2 gearbox assembly, IRB 4600 series, sealed grease-lubricated unit
• 3HAC029158-001: Axis-3 gearbox assembly, IRB 4600 series, compact reduction unit
• 3HAC029159-001: Axis-4 gearbox assembly, wrist section, IRB 4600
• 3HAC029160-001: Axis-5 gearbox assembly, wrist pitch reduction, IRB 4600
• 3HAC029161-001: Axis-6 gearbox assembly, wrist roll reduction, IRB 4600

Motor Units (Axis-Matched):

• 3HAC031683-001: Axis-1 servo motor, IRB 4600, compatible with 3HAC028837-008 gearbox
• 3HAC031684-001: Axis-2 servo motor, IRB 4600 series
• 3HAC031685-001: Axis-3 servo motor, IRB 4600 series
• 3HAC031686-001: Axis-4 servo motor, wrist section, IRB 4600

Mechanical & Structural Spares:

• 3HAC028838-001: Axis-1 output flange, IRB 4600, flat pattern (FP)
• 3HAC028839-001: Axis-1 bearing kit, gearbox input side, IRB 4600
• 3HAC028840-001: Axis-1 seal kit, gearbox output, IRB 4600 — recommended replacement at each gearbox R&R
• 3HAC028841-001: Gearbox grease kit, Optimol Longtime PD2, 400g — OEM-specified lubricant for IRB 4600 axis gearboxes
• 3HAC029162-001: Lower arm assembly, IRB 4600-20/2.50, includes axis-2/3 interface brackets
• 3HAC029163-001: Upper arm assembly, IRB 4600 series, wrist interface included
• 3HAC029164-001: Balancing device assembly, IRB 4600-40/2.55 and 4600-60/2.05 variants

Sourcing Hard-to-Find & Obsolete IRB 4600 Parts

The IRB 4600 platform entered its mature lifecycle phase approximately 2020–2022. ABB Robotics continues to supply new spare parts through authorized channels, but lead times for gearbox assemblies — particularly axis-1 and axis-2 units — have extended to 8–20 weeks from OEM stock in periods of high demand. For facilities operating multiple IRB 4600 cells, this lead time represents a material production risk.

DriveKNMS maintains a dedicated sourcing network for ABB IRB 4600 mechanical spares, including new-old-stock (NOS) gearbox assemblies, factory-refurbished units with documented test records, and cross-referenced compatible units from ABB's extended parts catalog. For obsolete revision suffixes (-001 through -005), DriveKNMS can provide traceability documentation confirming part origin and inspection status. All units are shipped with export compliance documentation suitable for customs clearance in EU, US, Southeast Asia, and Middle East markets.

Quality Control for the IRB 4600 Gearbox Range

Gearbox assemblies for the IRB 4600 series undergo the following verification steps at DriveKNMS before dispatch:

• Visual and dimensional inspection: Output flange runout, input shaft condition, housing integrity, and seal surface condition are checked against ABB mechanical tolerances.
• Backlash measurement: Rotational backlash at the output flange is measured and recorded. Units exceeding ABB's published tolerance for the relevant axis are rejected.
• Lubrication verification: Grease fill level and type are confirmed. Units with unknown lubrication history are purged and refilled with OEM-specified Optimol Longtime PD2.
• Revision marking verification: Part number suffix and date code are cross-referenced against ABB's spare parts database to confirm revision compatibility with the customer's robot serial number range.
• Packaging: Units are packed in anti-static foam with desiccant, suitable for air freight (DHL/FedEx) or sea freight consolidation.

A 12-month warranty is provided on all gearbox assemblies, covering manufacturing defects and premature failure under normal operating conditions. Warranty claims are processed with full RMA documentation.