PTG Holroyd has received an order for its 18th EX Series CNC helical rotor milling production centre from a global air compressor manufacturer, underlining a long-standing relationship between the two companies.
Currently being built at PTG Holroyd’s UK manufacturing facility, the machine, a 3EX-R-XL model, is scheduled for installation at one of the customer’s overseas production plants early next year. The machine will be used to rough mill rotor blanks up to 350mm in diameter for portable and stationary air compressors.
The latest machine incorporates PTG Holroyd’s new XL (extra component length) capability, which is now a standard feature across the company’s EX Series range. By incorporating a longer machine bed than previous models, the design provides the flexibility to machine longer helical components when required.
Mark Curran, sales director at PTG Holroyd, said: “If repeat orders are a sign of the faith a company places in a supplier and its technologies, this latest order is a considerable honour for our business.
“Although this will be the 18th Holroyd EX machine purchased by the customer, over the years they have bought more than 30 of our advanced machine tool technologies. Models sold to them include EX Series machines, CS Series cutter sharpener machines, and TF Series test fixture machines which are used to ensure the accurate measuring of rotor profile clearances.”
PTG Holroyd’s EX Series CNC helical rotor and pump-screw production centres are used worldwide for the manufacture of compressor rotors and related components, with the range recognised for its combination of speed, precision, productivity and long-term reliability.
The EX-R-XL line begins with the 2EX-R-XL, capable of milling helical components up to 250mm in diameter, and extends to the 8EX-R-XL, which can handle components up to 850mm in diameter. The portfolio also includes the dual-purpose 4EX-R-BL machine for rough and finish-milling helical rotors and Roots-type blower blanks up to 450mm in diameter and 1,960mm in length, as well as a custom-built 10EX-R-XL machine designed for rotor blanks exceeding 1,000mm in diameter.
All machines in the range are equipped with Siemens SINUMERIK ONE CNC control, providing integrated safety, security, reliability and production reporting capabilities. Fanuc control is available as an option.
PTG Holroyd says the EX-R-XL machines are designed to combine high stock-removal rates with exceptional accuracy. Their ability to undertake both roughing and finishing operations on a single platform helps reduce overall machining times, while accurate rough milling minimises the amount of material that must be removed during finishing. This reduces cycle times and helps improve component quality by limiting heat transfer to the workpiece during the finishing process.
The machines produce full-depth grooves by traversing the cutting tool through the material at the required helix angle while simultaneously rotating the component on the C axis. CNC-controlled digital drive technology maintains precise synchronisation between the axes throughout the machining cycle.
To maximise productivity, the EX Series incorporates features including high-speed operation, touchscreen menu-driven programming, quick-change tooling systems, high-power spindles and highly rigid machine construction. Additional technologies such as on-machine probing, dry milling capability for selected materials and compatibility with automated parts-handling systems further enhance manufacturing efficiency.
Part of the PTG group, which includes PTG Holroyd and Holroyd Precision Rotors, the company specialises in the design and manufacture of high-precision machine tools and helical component production systems. Its technologies are used across a wide range of industries, including refrigeration, air conditioning, aerospace, medical equipment, power generation, oil and gas, fluid transfer and high-end automotive applications.