Koike Aronson RK-350
Key Specifications
output current
input voltage
cut capacity mild steel production
cut capacity mild steel severance
cut capacity stainless
cut capacity aluminum
Overview
The Koike Aronson RK-350 is a 350-amp high-definition CNC plasma cutting system designed for heavy industrial plate cutting on large-format gantry tables. Koike Aronson, a joint venture between Japan's Koike Sanso Kogyo (founded 1918) and the United States-based Aronson Machine Company, brings decades of cutting machine engineering to the RK-350, which targets structural steel fabricators, shipbuilders, and heavy equipment manufacturers requiring reliable, high-capacity plasma cutting of plate from 6 mm to 75 mm.
The RK-350 is engineered around a heavy-duty gantry frame with precision rack-and-pinion drives on both sides of the X axis, providing the synchronized dual-drive motion that large-format plasma tables require for accurate cuts across 5x10 foot to 10x40 foot plate areas. The system pairs with Koike's own Suprarex plasma tables or can be integrated into custom gantry structures. The 350A plasma power supply is Koike's in-house design, delivering high-definition arc performance with a full Auto-Gas management system for oxygen, nitrogen, compressed air, and optional specialty gas lines.
Koike's CNC control on the RK-350, the Kcam system, provides an operator-friendly interface for nesting, process selection, and cut parameter management. The Kcam control is compatible with standard DXF and NC file import formats, making it straightforward to import geometry from most CAD and nesting software packages. Koike also offers integration with leading third-party nesting software for shops with existing nesting investments. True Hole and True Bevel process packages are available for mild steel hole and bevel quality optimization.
The RK-350 is a frequent choice for North American structural fabrication plants and shipyards due to Koike Aronson's strong US and Canadian dealer and service presence. A 5x10 foot table with RK-350 plasma system typically prices from $300,000 to $600,000 fully equipped. Koike's reputation for mechanical build quality — particularly in the drive system and torch carriage design — is a consistent strength noted by operators in heavy production environments.
Full Specifications
| Parameter | Value |
|---|---|
| Output Current | 30–350 A |
| Input Voltage | 380–600 V, 3-ph, 50/60 Hz |
| Cut Capacity Mild Steel Production | 50 mm (2 in) |
| Cut Capacity Mild Steel Severance | 75 mm (3 in) |
| Cut Capacity Stainless | 38 mm (1-1/2 in) production |
| Cut Capacity Aluminum | 38 mm (1-1/2 in) production |
| Gas System | Auto-Gas console (O2, N2, air, optional specialty) |
| Bevel Capability | ±45 degrees (optional bevel head) |
| True Hole | Available (mild steel, with optimized process) |
| Table Sizes | 5x10 ft to 10x40 ft (standard formats) |
| Drive System | Dual-side rack-and-pinion, servo-driven |
| Cnc Control | Koike Kcam |
Specifications sourced from koike.com — verified 2026-03-28
Strengths & Limitations
Strengths
- Heavy-duty dual-side rack-and-pinion gantry provides the mechanical rigidity needed for consistent cut accuracy across large-format plate in production conditions
- 350A high-definition output handles the full range of structural plate from 6 mm to 75 mm without needing a separate oxy-fuel system for thick sections
- Koike Aronson's strong North American dealer and service network provides responsive warranty and maintenance support for production-critical operations
- True Hole process package delivers bolt-ready holes in mild steel, reducing or eliminating secondary drilling in structural fabrication workflows
Limitations
- 350A maximum output is below the HPR400XD's 400A — shops cutting very heavy plate (above 65 mm) regularly at high speed may find the RK-350 at its practical limit
- Kcam CNC control, while functional, has a steeper learning curve for operators accustomed to Windows-based touch-screen controls from Hypertherm or Lincoln Electric systems
- Capital cost of $300,000–$600,000 for a complete system is justified by high cutting volume; light or intermittent heavy plate operations may find a conventional plasma system more economical
Best For
Frequently Asked Questions
01
The RK-350 uses Koike's proprietary 350A high-definition plasma power supply with an integrated Auto-Gas management console. Koike designs and manufactures the power supply in-house, which allows tight integration with the Kcam CNC control for process-optimized cutting parameters. Third-party plasma power supplies (Hypertherm, ESAB) can also be integrated in custom configurations.
02
The RK-350 is a complete table-and-power-supply system, while the XPR300 is primarily a plasma power supply that is integrated into various manufacturers' tables (including Koike's). The RK-350's 350A output exceeds the XPR300's 300A, giving it a cutting speed advantage on plate above 50 mm. For cut quality on mild steel under 50 mm, the XPR300's X-Definition technology is competitive or superior.
03
The RK-350 is offered on Koike Suprarex tables from 5x10 feet (1,500 x 3,000 mm) to 10x40 feet (3,000 x 12,000 mm) in standard configurations. Custom table sizes are available for shipyard and special applications. Dual-torch configurations for parallel cutting of two parts simultaneously are also available on wider tables.
04
Yes. An optional 5-axis bevel head is available that supports bevel angles up to ±45 degrees for V, Y, and K weld prep profiles. Bevel path programming is handled in Koike's Kcam control using the bevel programming module. Bevel cutting is commonly used on flanges, webs, and heavy plate edges to prepare for automated welding.
05
Koike Aronson maintains a network of authorized dealers and service representatives across the United States and Canada. The company's US headquarters is in Arcade, New York. Factory-trained service technicians are available for installation, commissioning, and warranty service. Koike stocks consumables and mechanical spare parts domestically for reduced lead times.
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