Rolling

We have always made chips.
Then we decided to add other things.

The roll threading technology (cold deformation of steel) was introduced by the founder, Paolo Montesi, in the beginning of the 1980s, representing a “special and little-known” process at the time, although it was already developed by German industry in the beginning of the twentieth century.

The first German rolling machines were a forerunner for deepening the advantages of the process that were related to productivity and cost-effectiveness of roll threading.

The company’s growth was also accompanied by the diffusion of Montesi rolled products on the Italian and European markets, so the brand became recognized in association with the product.

In recent decades, rolling experience has also expanded to include forming processes to obtain worms and splines, leading to Montesi being recognized as a reference company in Italy and Europe in the supply of high quality rolled products.

Today we are proud of our partnerships with major multi-national European companies in the supply and prototyping of mechanical components, where rolling has strategic importance.

THE ROLLING PROCESS AND ITS ADVANTAGES

Rolling is a mechanical process without chip removal that provides for the creation of threads, forming, and surface superfinishing by passing the piece between rolling tools in continuous rotation, which deform and refinish the outer surface of the raw material until the desired shape and sizes are reached.

Rolling is preferred to turning and grinding since plastic deformation on the piece involves the hardening of the material, increasing its hardness and preserving its mechanical properties. Also, since cracks cannot be detected, the rolled product has a better fatigue strength.

This is a process appreciated in fields such as aerospace (e.g., screws without cracks), automotive (splines on the engine shaft), and the railway, oil & gas, wind turbine, and off-road fields (earthmoving and farming machines), also thanks to the reduction in costs of the product.

The advantages of the rolling process can be summed up as follows:

  • In threading, an increase in resistance of the thread tooth is obtained, with subsequent greater resistance to wear.
  • In general, excellent roughness is obtained on the thread side and on the base radius, also improving the values that can be obtained by grinding.
  • No interruption in the progress of the fibre of the raw material, unlike removed or milled threading.
  • Reduced sensitivity to notching.
  • Increased productivity and resulting efficiency and cost-effectiveness of the process.
APPLICATIONS FOR THREADING

BAR THREADING TO OBTAIN MANOEUVRING SCREWS, MOVEMENT SCREWS, AND BALL RECIRCULATION SCREWS

The so-called “in passing” roll threading process typically starts from the processing of steel bars, which are completely threaded.

From this, screws in the length desired are obtained, which are processed at the ends for support and motion transmission.

Screws threaded by rolling, paired with sliding nuts, constitute a translation system used in a wide range of applications, both for manoeuvring heavy loads (rolled trapezoidal screws) and for moving lighter equipment with the need for greater speed (movement screws).

Roll threading also allows the creation of profiles for pairing with ball circulation nuts. Rolled screws for ball circulation nuts are one of the excellent potentials of roll threading, where precision is reached with advanced technology and processes with CNC numeric control.

ROLL THREADING OF SEMI-FINISHED PRODUCTS

The so called “dive” roll threading starts with the processing of previously turned components.

The excellence of the end result is also related to the quality of the preparatory turning phase, a synergy with which we have vast experience and expertise.

Roll threading on mechanical components (M, Tr, WhitWorth, UNC, UNF, UNEF threads) is a choice bound for special used (avionics) and ensures excellent resistance and finish.

Their synergy with our departments in the REMOVAL division allows a wide range of components with removed threading.

APPLICATIONS FOR FORMING

ROLLED WORMS

With rolling, plastic shaping of steel can be obtained to create precision worms, which are typically paired with crown gears in angular motion transmission or reduction applications.

These are processes where the movement of the material is very high and therefore, millesimal control of the large compression power involved is fundamental.

The most suitable generation of rolling machines is the numerically controlled one, which can manage the PSF (precision screw forming) process.

Rolling on tailstocks is the most advanced technical solution to create worms with an appreciable degree of precision, even in applications where worms obtained by notch forming are usually used.

ROLLED SPLINES (PARALLEL SPLINING)

Forced seating is a type of shaft-hub connection.

The shaft spline can be obtained by rolling using a rack or rollers.

Rack splining offers process stability and high productivity.

Splining with rollers offers size flexibility and extreme precision on the involutes.

APPLICATIONS FOR SURFACE SUPERFINISHING

Rolled superfinishing, also known as lapping, may be considered to be an excellent solution for obtaining surface finishes on cylindrical parts with low roughness.

The roughness values that can be obtained with this process are better than grinding and can be performed in a highly efficient and economical manner.

The synergy and continuous feedback between turning and the subsequent rolled superfinishing are indispensable for obtaining excellent results.

Shafts, rods, and drive screws in the valve sector are just a few of the typical applications of this process.

THE MONTESI ADVANTAGES IN PRODUCTS WITH ROLL THREADING

SCREWS

  • Availability of a vast warehouse of rolling tools for different types of thread geometry.
  • Wide range of diameters obtainable, left-right versions, single and multi start.
  • Screws in carbon steel, ETG, special high-resistance steels, stainless steel, and aluminium. • Standard product range available in the warehouse and on the industrial distribution market.

NUTS

  • Specialisation in high quality turning threading for obtain nuts that ensure excellent pairing on rolled screws of every thread type.
  •  Control and customization of the screw coupling runouts.
  • Highly productive and flexible turning department for the production of nuts with conventional or non-standard shapes.
  • Processing of metal and plastic materials.
  • Innovative solutions for dual material modular nuts.

MADE-TO-ORDER AND SPECIAL PRODUCTS

  • Rolled screws with end processing made-to-order according to the support and motion transmission requirements identified by the designer.
  • Nuts in special materials and with processing of the shapes according to the requirements identified by the designer.
  • Setup of special thread profiles in collaboration with our rolling tools supplier partners.
  • Possibility of laboratory tests to empirically measure the performance of the nut-screw system.
  • Collaboration with primary treatment companies to provide special protective surface coatings or those that improve the friction coefficient.

More details in the Products to design page

EQUIPMENT

Rolling machines:

  • 1 high-precision CNC rolling machine for rolling on tailstocks
  • 1 CNC rolling machine for bar threading
  • 4 rolling machines for bar threading
  • 1 rolling machine for special plunge threading

Rack forming rolling machine:

  • • 1 unit for rolled splines with automation
  • 1 manned unit for rolled splines

Rolling tools:

  • Extensive roller warehouse

ROLL THREADING TECHNOLOGY

Trapezoidal profile manoeuvring screw threading

Drive/multi-start screw threading

Recirculation screw threading

Automated straightening

Learn more

ROLL FORMING TECHNOLOGY

Worm forming

Spline forming

Learn more

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WHY CHOOSE MONTESI

  • Technological leader in Italy in rolling processes.
  • Standard products and products made to design to cover the needs of different market segments.
  • Rolling studies and tests on special products being prototyped to optimize their performance.
  • Experience in diverse industries, from construction to motor sports (Formula 1).
  • Partnerships with outstanding suppliers throughout the world in the production of rolling machinery and tools.