EC210 Swing Gearbox 2nd Planetary Carrier Spider With Sun Gear Assy For Excavator Parts SA7118-30200 SA7118-30390

EC210 Swing Gearbox 2nd Planetary Carrier Spider With Sun Gear Assy For Excavator Parts SA7118‑30200 SA7118‑30390

Product Overview

This integrated 2nd‑stage planetary carrier spider and sun gear assembly acts as the core intermediate transmission unit within the swing reduction gearbox of EC210 series excavators. Positioned between the first‑stage planetary input group and the final output section, it undertakes secondary deceleration and torque amplification, transferring rotational power to drive upper‑structure slewing for digging, backfilling, loading and ground‑leveling tasks. EC210 medium excavators are widely deployed in road building, urban reconstruction, farmland renovation and general earth‑moving projects, where the second‑stage planetary set endures continuous alternating torque as well as frequent forward‑reverse swing impacts. Common wear failures cover gear tooth surface spalling, sun gear spline abrasion, carrier pin hole distortion, fatigue micro‑cracks and persistent metallic grinding sound during rotation. This brand‑new aftermarket complete assembly can directly replace the worn original component, effectively resolving typical gearbox malfunctions such as weak swing output, rotational stutter and slow slewing response. Cross‑reference OEM part numbers: SA7118‑30200, SA7118‑30390. All mounting sizes, spline parameters and gear modulus are strictly manufactured according to original specifications to achieve perfect fit inside EC210 swing gearbox without structure alteration.

Technical Specification

Product Highlights

1. Enhanced one‑piece forging structure: The planetary carrier spider is formed from integral forged alloy steel blank, greatly boosting structural rigidity and deformation resistance. It can cope with repeated alternating impact torque generated by frequent swing start‑stop under medium‑load working scenarios, lowering failure risks including pin‑hole oval deformation and carrier body fracture.
2. Rigorous gear finishing craftsmanship: The matched sun gear undergoes carburizing quenching followed by fine tooth grinding processing. Precise tooth profile ensures reasonable and consistent meshing clearance together with planetary gears and inner ring gear. It cuts down internal friction heat, dampens abnormal knocking noise during slewing, and prolongs the overall service life of the whole swing gear train.
3. Ready‑to‑use pre‑assembled module: Delivered as an integrated finished assembly instead of scattered separate spare parts. Field maintenance personnel are freed from complicated gear matching and manual assembling work onsite. It drastically shortens gearbox overhaul cycles and reduces economic losses caused by equipment downtime for repair shops and construction contractors.
4. Reliable aftermarket interchangeability: Every critical dimension complies with OEM drawing standards. No cutting, grinding or secondary modification is required in the course of installation. It is an ideal cost‑efficient inventory selection for global spare‑parts distributors, machinery service centers and used‑excavator refurbishment projects.

Manufacturing & Quality Control

Our manufacturing workshop owns the full production chain covering forging processing, multi‑axis CNC machining, professional heat treatment and high‑accuracy gear grinding. Each incoming batch of alloy steel raw material will be subject to strict inspection on chemical composition and mechanical performance. Key indicators including carrier pin‑hole spacing, sun gear tooth profile and spline dimension are fully inspected for every single finished unit. Random sampling impact‑torque simulation tests are implemented to validate real‑world load‑bearing performance and gear meshing stability. Qualified assemblies are wrapped with anti‑rust film, padded with shock‑absorbing filler and sealed in heavy‑duty wooden crates to avoid surface scratch, collision damage and oxidation rust during cross‑border sea and land long‑haul transportation. Any non‑conforming product will be rejected before packing and shipment.

FAQ

1. Q1: What warning symptoms tell us to replace this second‑stage planetary assembly? A: Obvious metal grinding noise while the excavator swings, insufficient swing torque, intermittent rotation jitter, iron powder or fine metal debris mixed in swing gear grease. Under these circumstances, you need to disassemble the gearbox housing and check the second‑stage planetary components.
2. Q2: Can this assembly fit other excavator models? A: This component is specially developed for EC210 series swing gearbox. If you plan to install it on other machine models, please carefully verify your old part numbers and the actual internal structure of gearbox to prevent incorrect purchase.
3. Q3: What essential points should be observed during installation? A: Completely clean the inner cavity of gearbox housing and thoroughly remove residual metal debris. Fill high‑temperature resistant special swing gear grease after component installation. Conduct low‑speed no‑load swing running‑in at first; do not put the machine into full‑load digging and slewing operation immediately after repair completion.
4. Q4: What is covered under product warranty? A: We provide standard aftermarket warranty against manufacturing‑related defects. Damage induced by hard foreign objects entering gearbox interior, improper assembling operation and long‑term overload work is not covered. Please strictly follow official swing reducer maintenance guidance.
5. Q5: About delivery solutions? A: In‑stock products can be dispatched within 3‑7 working days. Multiple logistics options including sea freight, air freight and express delivery are available to satisfy diverse requirements for bulk consignments and urgent orders from worldwide customers.