Komatsu PC200-6 Swing Gearbox 2nd Planetary Carrier Spider With Sun Gear Assy

Komatsu PC200‑6 Swing Gearbox 2nd Planetary Carrier Spider With Sun Gear Assy For 20Y‑26‑21160 20Y‑26‑21220 20Y‑26‑21210

Product Overview

This is the second‑stage planetary carrier spider integrated with sun gear assembly, a core transmission component installed inside swing reduction gearbox for Komatsu PC200‑6 crawler excavator. It undertakes torque amplification and speed‑reduction transmission tasks, transferring power from first‑stage planetary set to subsequent gear components to drive upper‑structure slewing motion. This 20‑ton machine is widely engaged in earth‑moving, foundation excavation, material stacking and urban reconstruction projects. Under continuous shock load and frequent slewing cycles, poor gear‑oil maintenance or seal failure will introduce metal debris and dust into gearbox chamber, triggering tooth surface pitting, gear abrasion and carrier deformation. Typical failure symptoms cover grinding noise inside swing gearbox, jerky and unstable cabin rotation, insufficient swing torque, abnormal housing temperature rise and metallic particles found in swing gear oil. Manufactured strictly following original drawing dimension standards and gear‑meshing parameters, this assembly supports direct replacement installation, helping repair shops and machine owners restore stable swing performance while avoiding secondary damage to other costly internal gearbox parts.

Technical Specification

Core Advantages

1. Heavy‑load optimized alloy steel for excavator swing shock‑load conditions The carrier spider and sun gear adopt premium alloy steel raw material. After carburizing quenching and precise gear‑grinding process, gear teeth gain high surface hardness together with good core toughness. It effectively resists impact torque generated during frequent start‑stop swing operations, lowering risks of tooth chipping and carrier deformation under harsh site surroundings.
2. Strictly controlled gear‑meshing tolerance for smooth slewing performance Every finished assembly undergoes gear‑meshing inspection before delivery. Precise tooth‑profile and backlash control reduces transmission vibration and abnormal grinding noise. It guarantees steady power output when excavator performs combined digging‑and‑swing actions, preventing jerky cabin rotation caused by poor meshing clearance.
3. Duplicated original mounting geometry to shorten on‑site repair cycle Key dimensions including carrier outer profile, sun‑gear spline specification and pin‑hole position fully match original OEM parts. Service technicians can complete assembly swap without re‑machining or adjusting gearbox internal structure. For rental fleets and local repair depots, it cuts machine downtime and avoids project delay losses caused by swing system malfunction.
4. Stress‑relief treatment enhances long‑term anti‑deformation capability Complete stress‑relief annealing eliminates internal forging stress, greatly improving structural stability under repeated heavy shock loads. Cooperated with precise matching tolerance for pin shaft and bearing position, it reduces early‑stage wear of related mating parts and extends overall service life of whole swing gearbox.
5. Economical reliable substitute for swing gearbox overhaul projects Original whole swing gearbox unit carries high replacement cost. Replacing worn second‑stage planetary carrier & sun gear assembly separately is a cost‑effective overhaul solution. It is well‑suited for machinery repair workshops, equipment rental operators and global Komatsu excavator spare‑parts distributors.

Manufacturing & Quality Control

Our production line focuses on planetary transmission components for Komatsu medium excavator swing gearboxes. Full‑process quality management covers raw‑material composition verification, forging inspection, heat‑treatment hardness testing, gear‑tooth precision detection, assembly dimensional checking and sample bench running‑in test. Only qualified assemblies can enter packaging workflow. Finished goods are coated with anti‑rust oil, wrapped by shock‑proof cushion material and packed in export‑standard fumigated wooden cases to prevent collision, corrosion during cross‑ocean logistics. We support bulk wholesale, stable batch supply, small trial orders are acceptable for global purchasers.

Frequently Asked Questions

Q1: What signs indicate second‑stage planetary carrier and sun‑gear assembly needs inspection or replacement? A: If your PC200‑6 excavator has loud grinding noise inside swing gearbox, stuttering swing rotation, insufficient swing power, excessive gearbox housing temperature, or metal powder is observed when draining swing gear oil, you need to disassemble swing reducer for component inspection timely.

Q2: Will this assembly fit other Komatsu excavator models? A: This unit is specially manufactured for Komatsu PC200‑6 swing gearbox. Some similar‑serial PC210‑6 / PC220‑6 may have different internal gearbox configurations. Please double‑check your OEM part numbers 20Y‑26‑21160, 20Y‑26‑21220, 20Y‑26‑21210 before placing order to avoid installation mismatch.

Q3: What key notes for installation work? A: Thoroughly clean all residual metal debris inside swing gearbox housing before installation. Inspect related planetary gears, bearings and sealing condition simultaneously. Fill up with qualified swing gear oil after assembly completion, and perform low‑load swing running‑in test under no‑load status before formal site operation.

Q4: Warranty scope explanation A: Our warranty covers defects originating from manufacturing and material flaws. Damage induced by foreign‑matter invasion, insufficient gear‑oil lubrication, over‑shock overload and improper disassembly‑installation will not be included in warranty scope. Please strictly follow Komatsu official service manual during swing gearbox overhaul.