USED OKUMA GP-47N

The Okuma GP-47N is a large-capacity CNC cylindrical grinding machine designed for precision external (OD) grinding of long and heavy workpieces. As part of Okuma’s GP-N series, it is specifically engineered for high-accuracy grinding of large shafts and cylindrical components, making it ideal for industries such as energy, automotive, heavy equipment, and general engineering. The machine is capable of handling workpieces up to approximately 400 mm in diameter and up to 3,150 mm in length, with a maximum weight capacity of around 1,800 kg.

A key feature of the GP-47N is its rigid machine structure, which includes wide V-flat guideways designed to provide excellent stability and minimize deflection during long grinding operations. This is particularly important when machining long shafts where maintaining consistent accuracy across the entire length is critical.

The machine is equipped with a large grinding wheel (approximately 760 mm diameter) powered by a spindle motor rated at around 15 kW (with optional higher power), enabling both heavy-duty material removal and fine finishing. The hydrodynamic wheel spindle ensures smooth rotation, high rigidity, and reduced vibration, resulting in improved surface finish and dimensional accuracy.

The GP-47N uses Okuma’s OSP-P300GA control system with IGAP+ conversational programming, simplifying setup and operation for complex grinding tasks. Rapid traverse speeds of approximately 12 m/min (X-axis) and 10 m/min (Z-axis) help reduce idle time and increase overall productivity.

Designed for high grinding (cutting) time utilization, the machine supports automation integration such as loaders and handling systems. Overall, the GP-47N offers a strong combination of size, rigidity, and precision, making it a reliable solution for large-part cylindrical grinding applications.

OKUMA GP-47N SPECIFICATIONS

WHY BUY USED OKUMA GP-47N

Buying a used Okuma GP-47N is a strategic decision for manufacturers that require large-part grinding capability without the high capital investment of a new machine. Machines in this category are built with heavy-duty construction and precision components, allowing them to maintain performance and accuracy over long periods when properly maintained.

One of the main advantages of purchasing used is cost efficiency. Large cylindrical grinders like the GP-47N can be expensive when new, especially when configured with automation systems and advanced controls. A used machine allows businesses to access the same large work envelope, high spindle power, and rigid construction at a significantly lower cost, improving return on investment.

Grinding time (spindle hours) is one of the most critical factors when evaluating a used GP-47N. Machines with lower grinding hours generally retain better spindle accuracy and guideway condition. For example, a machine from the early 2010s with moderate grinding time may provide better reliability than a newer unit that has been heavily used in continuous production. Since this machine is often used for long shaft grinding, wear on guideways, tailstock, and steady-rest areas should be carefully inspected.

Another advantage is process capability. The GP-47N is designed for heavy-duty, long-length grinding operations, and even in a used condition, it can significantly improve workflow efficiency by reducing setups and handling time for large components. Additionally, Okuma’s strong global support network and parts availability help reduce the risks associated with purchasing older equipment.

From a financial perspective, buying used enables faster payback. With lower upfront costs and the ability to sustain long grinding cycles, a used GP-47N can quickly contribute to production output and profitability in heavy manufacturing environments.

HOW MUCH DOES A USED OKUMA GP-47N COST?

The cost of a used Okuma GP-47N varies depending on factors such as manufacturing year, machine condition, configuration, and most importantly, grinding time (spindle hours). As a large-capacity cylindrical grinder, it typically commands higher prices than smaller grinding machines but offers significant value due to its size and capability.

Machines built before 2000 (or earlier-generation large cylindrical grinders comparable to this platform) generally range from $20,000 to $60,000. These machines are the most affordable but may include older control systems and higher wear levels. Grinding time is especially important in this category—machines with high spindle hours may require refurbishment, while low-hour units can still be viable for lighter production applications.

Models produced between 2000 and 2010 typically range from $60,000 to $140,000. This segment often provides the best balance between price and performance, offering improved control systems, better spindle technology, and enhanced machine rigidity. Units with low to moderate grinding time are particularly desirable, as they can deliver reliable accuracy with manageable maintenance costs.

Machines from 2010 to 2025 generally range from $140,000 to $300,000 or more, depending on configuration, automation integration, and control upgrades. These newer machines benefit from improved efficiency, better thermal stability, and enhanced consistency in long production runs.

Grinding time remains the most critical 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, and maintenance history to determine true market value and ensure long-term operational reliability.