Rochdale-based PTG Holroyd Precision has introduced the HG500, a groundbreaking machine designed to be the most versatile and ultra-high-performance solution for precision grinding of helical profiles, widely used in the air and refrigeration compressor industry.
Developed to meet the diverse production needs of manufacturers, the HG500 can grind helical rotors ranging from 50mm to 510mm in diameter, with a profile depth of 130mm and a weight capacity of up to 1,500kg. This versatility is critical for producing some of the largest helical rotors used in refrigeration and air-compressor manufacturing.
Mark Curran, PTG Holroyd’s sales director, explained the inspiration behind the HG500’s design: “Following customer feedback and the success of our TG Series of thread grinding machines, we identified a demand for a new, large-capacity helical rotor grinding machine. With the HG500, we’ve developed a solution that not only accommodates a wide variety of rotor sizes but also handles the largest, most energy-efficient helical profiles.”
The HG500 offers two main grinding wheel options: a 500mm vitrified dressable aluminium oxide wheel for flexibility in production, or plated CBN roughing and finishing wheels for cost-effective volume production. For manufacturers working with the largest helical components, a 600mm grinding wheel is available to maximize wheel life.
A key feature of the HG500 is its use of the Siemens Sinumerik One CNC, which PTG Holroyd was the first UK manufacturer to implement. This collaboration with Siemens has allowed the company to tailor the CNC’s capabilities to its specific needs, including enhanced safety features, real-time machine health monitoring, and faster, more secure operation. The HG500 also includes additional Profinet and OPC/UA interfaces for improved connectivity and performance.
To further enhance precision, the HG500 uses a travelling grinding head instead of a conventional grinding table, enabling maximum probing capabilities with the onboard Renishaw OSP60 scanning probe, equipped with SPRINT technology. The machine also features an intelligent, variable-frequency cooling system, ensuring efficient coolant use, and programmable ‘eco’ modes to minimize energy consumption during non-productive cycles.
Curran emphasized the machine’s user-friendly setup: “The HG500 is designed to make complex processes simple. Its intuitive setup allows for rapid changeover of batches, and its CNC-controlled dressing system automatically corrects wheel profiles for each cycle, with programmable feed rates for both roughing and finishing stages.”
The HG500 also integrates PTG Holroyd’s Holroyd Profile Management System (HPMS), an advanced suite of programs that simplifies profile manipulation and analysis. HPMS helps control helical profiles during production and provides real-time adjustments for wheel and profile corrections.
Key features of the HG500 include:
- Grinding capacity from 50mm to 510mm in diameter, with up to 1,500kg component weight
- Vitrified dressable Al2O3 or plated CBN grinding wheels
- Optional 600mm grinding wheel for larger components
- Siemens Sinumerik One CNC and integrated profile management system
- Automated wheel profile correction and simplified setup
- Renishaw OSP60 scanning probe with SPRINT technology
- High-pressure, variable-frequency cooling system
- Programmable eco modes to reduce energy usage
- Holroyd Profile Management System (HPMS) for precise profile control and in-cycle corrections.
With the HG500, PTG Holroyd Precision sets a new standard for flexibility, performance, and energy efficiency in helical rotor grinding, catering to the growing demands of the compressor industry.