USED OKUMA GP-67N

The Okuma GP-67N is the largest model in Okuma’s GP-N series of CNC cylindrical grinding machines, designed specifically for high-precision external grinding of very large and heavy workpieces. It is built for industries such as energy (turbines, shafts), heavy machinery, automotive, and large industrial components where long, high-accuracy cylindrical grinding is required. The machine is engineered to handle demanding production environments while maintaining rigidity, accuracy, and thermal stability over long cycles.

The GP-67N supports a maximum grinding diameter of approximately 650 mm and can accommodate workpiece lengths up to 3,150 mm, depending on configuration. It can handle workpieces weighing up to around 1,800 kg, making it suitable for heavy-duty shaft and roll grinding applications. The machine uses a large grinding wheel system (around 760 mm diameter), paired with a powerful spindle motor typically rated at 15 kW, with optional upgrades up to 22 kW for more aggressive material removal.

A major strength of the GP-67N is its structural rigidity. It features a wide V-flat guideway design that ensures stability and minimizes deflection during long grinding passes. This is especially important when machining long shafts where consistent diameter and surface finish must be maintained across the entire length. The hydrodynamic wheel spindle further enhances precision by reducing vibration and maintaining smooth rotational accuracy during heavy-duty grinding operations.

The machine is controlled by Okuma’s OSP-P300GA system, which includes IGAP+ conversational programming. This simplifies setup and allows operators to efficiently program complex grinding cycles such as plunge, traverse, taper, and form grinding. Rapid traverse speeds of approximately 12 m/min (X-axis) and 10 m/min (Z-axis) help reduce idle time and improve overall productivity.

Designed for maximum grinding (cutting) time utilization, the GP-67N is also compatible with automation systems such as loaders and material handling equipment. Overall, it delivers a strong combination of size, rigidity, and precision, making it one of the most capable cylindrical grinders in its class.

OKUMA GP-67N SPECIFICATIONS

WHY BUY USED OKUMA GP-67N

Buying a used Okuma GP-67N is a highly practical decision for manufacturers that require large-scale cylindrical grinding capability without the significant capital investment required for a new machine. Machines in this category are built with heavy-duty castings, high-power spindles, and precision guideways, allowing them to maintain performance and accuracy over long operational lifespans when properly maintained.

One of the main advantages of buying used is cost savings. A new GP-67N represents a major investment due to its size, power, and automation compatibility. A used machine provides access to the same large work envelope, high spindle power, and rigid grinding structure at a significantly reduced price, making it ideal for companies expanding production capacity or entering heavy machining applications.

Grinding time (spindle hours) is the most critical factor when evaluating a used GP-67N. Machines with lower grinding hours generally retain better spindle accuracy, guideway condition, and overall geometric precision. For example, a machine from the early 2010s with moderate grinding time may provide better long-term reliability than a newer machine that has been heavily used in continuous production. Since this model is typically used for long shaft grinding, wear on tailstock alignment, steady rest systems, and bed guideways should be carefully inspected.

Another advantage is production capability. Even in used condition, the GP-67N can significantly improve workflow efficiency by reducing setups for long and heavy parts. Its ability to maintain high precision over extended grinding cycles makes it valuable in both low-volume heavy machining and continuous production environments.

From a financial perspective, buying used allows faster return on investment. Lower upfront cost combined with high productivity and long grinding cycles makes the used GP-67N a strong asset for heavy engineering operations.

HOW MUCH DOES A USED OKUMA GP-67N COST?

The cost of a used Okuma GP-67N depends on manufacturing year, machine condition, configuration, and most importantly, grinding time (spindle hours). As the largest and most powerful model in the GP-N series, it typically commands a premium in the used market compared to smaller cylindrical grinders.

Machines built before 2000 (or earlier-generation large cylindrical grinders with similar capacity) generally range from $25,000 to $70,000. These units are the most affordable but may include older CNC controls, higher wear levels, and reduced automation capability. Machines with high grinding time in this category may require spindle refurbishment or guideway reconditioning.

Machines produced between 2000 and 2010 typically range from $70,000 to $160,000. This range often provides the best balance between price and performance, offering improved control systems, better spindle stability, and stronger thermal compensation. Units with low to moderate grinding time are especially valuable, as they can deliver reliable accuracy with lower maintenance requirements.

Machines from 2010 to 2025 generally range from $160,000 to $350,000 or more depending on configuration, spindle upgrades (15 kW vs 22 kW), automation integration, and overall condition. These newer machines benefit from improved efficiency, better vibration control, and enhanced suitability for continuous production environments.

Grinding time remains the most important pricing factor. A newer machine with excessive spindle hours may be less valuable than an older unit with minimal use. Buyers should carefully evaluate spindle condition, guideway wear, tailstock alignment, and maintenance history to determine true market value and ensure long-term operational reliability.