KR 120 R3900-2 K vs Welding Positioners
Side-by-side comparison of KR 120 R3900-2 K (KUKA Robotics) and Welding Positioners (Sankyo Automation) — specs, pricing, Robo Score, and verified deployments. Updated daily.
Optimize comparison for buyer
Layer 1: Identity & Trust
Manufacturer Country
- KR 120 R3900-2 KGermany
- Welding PositionersUnited States
Year First Available
- KR 120 R3900-2 K2015
- Welding Positioners—
Verified Deployments
- KR 120 R3900-2 K0 Deployments
- Welding Positioners0 Deployments
Layer 2: Operational
Price
- KR 120 R3900-2 K$19,000–$84,900 USD
- Welding PositionersContact for quote
Availability Status
- KR 120 R3900-2 KACTIVE
- Welding PositionersACTIVE
Arm Mechanics
Payload
- KR 120 R3900-2 K146 kg
- Welding Positioners3,600 kg
Reach
- KR 120 R3900-2 K3,904 mm
- Welding Positioners900 mm
Degrees of Freedom
- KR 120 R3900-2 K6
- Welding Positioners2
Repeatability
- KR 120 R3900-2 K±0.04 mm
- Welding Positioners±0.05 mm
Path Accuracy
- KR 120 R3900-2 K—
- Welding Positioners±0.1 mm
Robot Weight
- KR 120 R3900-2 K42 kg
- Welding Positioners780 kg
IP Rating (Arm)
- KR 120 R3900-2 KIP65
- Welding PositionersIP67
IP Rating (Wrist)
- KR 120 R3900-2 KIP67
- Welding PositionersIP67
Performance
Cycle Time (25/305/25)
- KR 120 R3900-2 K—
- Welding Positioners0.9 s
MTBF
- KR 120 R3900-2 K—
- Welding Positioners80,000 hrs
Duty Cycle
- KR 120 R3900-2 K—
- Welding Positionerscontinuous 24 7
Vibration Damping
- KR 120 R3900-2 K—
- Welding Positionersactive model based
Safety
Safety Category
- KR 120 R3900-2 K—
- Welding PositionersCat.3 PLd
Dual Check Safety
- KR 120 R3900-2 K—
- Welding PositionersYes
Safety I/O Pairs
- KR 120 R3900-2 K—
- Welding Positioners4
E-Stop Response
- KR 120 R3900-2 K—
- Welding Positioners20 ms
Safe Zone Count
- KR 120 R3900-2 K—
- Welding Positioners4
Controller & Programming
Controller Model
- KR 120 R3900-2 KKR C5, KR C5 micro
- Welding PositionersKR C4 KRC
Programming Languages
- KR 120 R3900-2 K—
- Welding PositionersKRL
Teach Pendant Type
- KR 120 R3900-2 K—
- Welding Positionerswired button
Offline Programming
- KR 120 R3900-2 K—
- Welding PositionersKUKA.Sim Pro
Digital Twin Support
- KR 120 R3900-2 K—
- Welding PositionersNo
Connectivity
ROS-Industrial Support
- KR 120 R3900-2 K—
- Welding Positionersnone
IoT / Cloud Platform
- KR 120 R3900-2 K—
- Welding PositionersKUKA Connect
Cybersecurity Certs
- KR 120 R3900-2 K—
- Welding PositionersIEC 62443 SL1
Predictive Maintenance
- KR 120 R3900-2 K—
- Welding Positionersthreshold based
End-Effector
Tool Flange Standard
- KR 120 R3900-2 K—
- Welding PositionersISO 9409-1
Tool Changer (ISO)
- KR 120 R3900-2 K—
- Welding Positionersproprietary
Internal Cable Routing
- KR 120 R3900-2 K—
- Welding Positionersexternal only
Pneumatic Lines
- KR 120 R3900-2 K—
- Welding Positioners2
Electrical Lines
- KR 120 R3900-2 K—
- Welding Positioners10
Commercial
Price (USD)
- KR 120 R3900-2 K$19,000–$84,900 USD
- Welding PositionersContact for quote
Warranty
- KR 120 R3900-2 K2 yrs
- Welding Positioners1 yrs
Service Network
- KR 120 R3900-2 Kglobal
- Welding Positionersglobal
Spare Parts Lead Time
- KR 120 R3900-2 K—
- Welding Positioners14 days
Expected Service Life
- KR 120 R3900-2 K—
- Welding Positioners10 yrs
| | |
|---|---|---|
| Layer 1: Identity & Trust | ||
| Manufacturer Country (values differ) | Germany | United States |
| Year First Available (values differ) | 2015 | — |
| Verified Deployments | 0 Deployments | 0 Deployments |
| Layer 2: Operational | ||
| Price (values differ) | $19,000–$84,900 USD | Contact for quote |
| Availability Status | ACTIVE | ACTIVE |
| Layer 3: Category Specific | ||
| Arm Mechanics | ||
| Payload (values differ) | 146 kg | 3,600 kg |
| Reach (values differ) | 3,904 mm | 900 mm |
| Degrees of Freedom (values differ) | 6 | 2 |
| Repeatability (values differ) | ±0.04 mm | ±0.05 mm |
| Path Accuracy (values differ) | — | ±0.1 mm |
| Robot Weight (values differ) | 42 kg | 780 kg |
| IP Rating (Arm) (values differ) | IP65 | IP67 |
| IP Rating (Wrist) | IP67 | IP67 |
| Performance | ||
| Cycle Time (25/305/25) (values differ) | — | 0.9 s |
| MTBF (values differ) | — | 80,000 hrs |
| Duty Cycle (values differ) | — | continuous 24 7 |
| Vibration Damping (values differ) | — | active model based |
| Safety | ||
| Safety Category (values differ) | — | Cat.3 PLd |
| Dual Check Safety (values differ) | — | Yes |
| Safety I/O Pairs (values differ) | — | 4 |
| E-Stop Response (values differ) | — | 20 ms |
| Safe Zone Count (values differ) | — | 4 |
| Controller & Programming | ||
| Controller Model (values differ) | KR C5, KR C5 micro | KR C4 KRC |
| Programming Languages (values differ) | — | KRL |
| Teach Pendant Type (values differ) | — | wired button |
| Offline Programming (values differ) | — | KUKA.Sim Pro |
| Digital Twin Support (values differ) | — | No |
| Connectivity | ||
| ROS-Industrial Support (values differ) | — | none |
| IoT / Cloud Platform (values differ) | — | KUKA Connect |
| Cybersecurity Certs (values differ) | — | IEC 62443 SL1 |
| Predictive Maintenance (values differ) | — | threshold based |
| End-Effector | ||
| Tool Flange Standard (values differ) | — | ISO 9409-1 |
| Tool Changer (ISO) (values differ) | — | proprietary |
| Internal Cable Routing (values differ) | — | external only |
| Pneumatic Lines (values differ) | — | 2 |
| Electrical Lines (values differ) | — | 10 |
| Commercial | ||
| Price (USD) (values differ) | $19,000–$84,900 USD | Contact for quote |
| Warranty (values differ) | 2 yrs | 1 yrs |
| Service Network | global | global |
| Spare Parts Lead Time (values differ) | — | 14 days |
| Expected Service Life (values differ) | — | 10 yrs |
Insufficient data for full comparison
The following fields had no data for any of the selected robots: Battery / Shift Runtime, Max TCP Speed, Communication Protocols
ROI Comparison
Same operating assumptions across every robot — the only difference is price. Set your numbers once to see which pays back fastest.
Annual labor displaced (per robot): $50,000
| Metric | KR 120 R3900-2 K | Welding Positioners |
|---|---|---|
| Investment | $51,950 | No price |
| Payback period | 12.5 mo | — |
| Net savings (5 yr) | $198,050 | — |
| ROI (5 yr) | +381% | — |
Welding Positioners has no listed price, so payback can't be computed. Contact the manufacturer for a quote.
Estimates labor-cost displacement only — not a full total cost of ownership. Actual ROI depends on integration, maintenance, training, downtime, and task fit. Converted currencies are indicative; USD is the price of record.
Trade-offs at a glance
Frequently asked
Who makes KR 120 R3900-2 K and Welding Positioners?
KR 120 R3900-2 K is made by KUKA Robotics, based in DE. Welding Positioners is made by Sankyo Automation, based in US.
How do KR 120 R3900-2 K and Welding Positioners compare on the Robo Score?
KR 120 R3900-2 K scores 78.0 on the Robo Score. Welding Positioners scores 55.2. The Robo Score is a 0–100 credibility figure blending commercial maturity, verified deployments, company standing, and independent coverage — see methodology for the full breakdown.
How does the reach of KR 120 R3900-2 K compare to Welding Positioners?
KR 120 R3900-2 K has a reach of 3904 mm. Welding Positioners has a reach of 900 mm.
Are KR 120 R3900-2 K and Welding Positioners in the same category?
Both robots are classified as Industrial Arm on Robolist. Filters and ranking treat them as direct alternatives.
What is the realistic total cost of ownership for Industrial Arm robots?
Hardware cost is one input. Industrial Arm TCO also includes integration, training, downtime, and end-of-life. Our breakdown: TCO of a 6-Axis Arm Cell: Hardware, EOAT, Integration, Programming.
What should a buyer ask vendors when choosing between KR 120 R3900-2 K and Welding Positioners?
Spec sheets only show part of the story. Useful vendor questions cover support, lifecycle, integration cost, and references. We have a buyer-focused checklist: Industrial Arm Vendor Selection: Capability Matrices and Proof Points.
Going deeper — picking the right robot
TCO of a 6-Axis Arm Cell: Hardware, EOAT, Integration, Programming
7 min readIndustrial Arms
Industrial Arm Vendor Selection: Capability Matrices and Proof Points
9 min readIndustrial Arms
Programming Approaches: Teach Pendant, Offline, AI-Assisted — What Each Costs You
8 min readIndustrial Arms
Build vs buy vs lease: which model fits a first deployment
8 min readChoosing Your First Robot
The hidden specs vendors hope you'll miss
10 min readReading the Spec Sheet
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About this comparison
KR 120 R3900-2 K vs Welding Positioners compares two robots in the industrial-arm category. All data is sourced from manufacturer spec sheets, verified deployments, and third-party filings; see our methodology for how the Robo Score is calculated.