DELTA expands travelling column range with high-capacity Mini 20 surface grinding machine
Published:
DELTA S.r.l., a specialist in high-tech flat-surface grinding machines, has announced the introduction of the new Mini 20 model, significantly extending the capacity range of its popular Mini travelling-column line. Available through UK agent RK International Machine Tools Ltd, the fully automatic Mini 20 is designed for high-precision applications, offering a maximum grinding length of 2,100 mm and a max grinding width of 600 mm, or 650 mm with the 100 mm wheel option.
A heritage in grinding excellence
DELTA was established in Pavia, Italy, in 1955 by Oreste Marchesi and Pietro Ceri. Initially a precision metalworking shop, the company quickly pivoted to producing surface grinders. A fundamental step in DELTA’s development occurred in the late 1960s, with the design and construction of flat-surface grinding machines that incorporated the high-accuracy Mackensen hydrodynamic spindle as a standard feature.
In the early 1980s, DELTA pioneered the use of the travelling column design in large-size surface grinders, the Maxi family, a structure previously seen mainly in milling and boring machines.
The company successfully scaled this technology to the smaller end of the market with the introduction of the Mini family in 2005. Today, DELTA manufactures its machines at its modern headquarters in Cura Carpignano, near Pavia, Italy and is recognised as a leader in the production of travelling column grinding machines.
Mini 20 technical specifications and features
The Mini 20 is a high-precision, fully automatic horizontal-spindle plane-surface grinding machine designed for both mass-production and single-piece precision applications. The core innovation lies in its rigidity and movement systems:
1. Meehanite travelling column structure:
The machine’s foundational structures, including the base, table, column and wheel-head, are constructed entirely from high-quality, stress-relieved Meehanite cast iron. This structure, optimally designed using finite element analysis in collaboration with the Mechanical Engineering Department of the Polytechnic of Milan, provides maximum stiffness and high vibration absorption. The travelling column design eliminates the "overhang" error and stability problems typically associated with moving-head grinding machines, ensuring flatness.
2. Hydrostatic axes:
The Mini 20 features hydrostatic ways on all axes, X, Y, and Z, utilising a closed-loop pressurised oil delivery system. This provides significant operational advantages, including "zero wear", maintaining the machine's original geometric accuracy throughout its life and zero sliding friction, thereby enabling optimal exploitation of the installed power. The hydrostatic support eliminates "stick-slip," guaranteeing extremely smooth and highly accurate movements with superior repeatability. The large table, measuring 2,000 mm by 500 mm, always rests fully on the basement during longitudinal travel due to this full grip slideway system.
3. Mackensen hydrodynamic spindle:
The spindle is supported on the wheel side by an oversized Mackensen-type hydrodynamic bearing. The hydrodynamic principle ensures no metal-to-metal contact, resulting in extremely long life, quiet operation, zero wear and superior surface finish capability.
4. Control system:
The machine is offered with three levels of automation: Diastep, CN Plus Touch Screen and CNC. The standard Mini 20 Diastep model utilises the proprietary Diastep control unit, which is an intuitive, teachable grinding system developed entirely in-house by DELTA. This user-friendly control allows operators to manage surface, continuous or step-by-step, or plunge grinding cycles, rough and finish passes and automatic wheel dressing with compensation. Full machine operation is guaranteed after only a half-day of training.
The Mini 20 is suitable for handling substantial workpieces, supporting a maximum admissible load of 1,500 kg on the table, and the machine has an approximate net weight of 7,000 kg.
UK representation
RK International Machine Tools Ltd, the UK agent for DELTA, has been appointed to handle the introduction of the Delta Mini 20 to the UK and Ireland.
Simon Rood, director at RK International Machine Tools states: ‘’With a 15-year relationship between DELTA and RK International Machine Tools, we are seeing a growing number of customers become aware of the build quality and attention to detail, Where customers are demanding more accuracy from their grinding machine, the DELTA range performs to the highest levels.’’
Today, DELTA is still under the watch of the Ceri and Marchesi families, with two members from each family running the facility's daily operations in Italy.
RK International Machine Tools Ltd
