Cutting system streamlines manufacturing process
ANTONIO VENDRAMINI
Italy was one of the first countries in the world to really follow the development of industrial applications of laser technology—so much so that, at the end of the 1970s, Italian companies were exhibiting innovative systems for machining 2D and 3D metal structures for the first time. A lot of time has gone by since then, but Italian technology has always been present in the world of mechanical laser applications. Today, the industry is experiencing new successes at US agricultural machinery manufacturer Unverferth Manufacturing Co. (Shell Rock, IA) with the installation of a system to cut tubular structures. This system has been designed and built by TTM Laser S.p.A. (Cazzago San Martino, Italy) a specialist in the design and manufacture of laser machinery and systems for cutting and welding tubular parts and sheet metal components (see "Laser returns to the railway industry," ILS November 2012; also see FIGURE 1) relating to the system installed at the Rail Coach Factory, the Indian company that produces railway carriages for the country.
Lasers take the field
In 1948, Unverferth Manufacturing Co. began constructing and manufacturing wheels, extensions, and hardware for equipping agricultural machinery with two or three wheels. The response was so positive that it soon became the focal point for many farms worldwide. Today, with the many brands that make up the group, Unverferth manufactures grain trailers, spraying and weed-control tankers (FIGURE 2), and other related equipment. In recent years, the US company has turned increasingly to laser technology to try to solve a long-standing problem, which involved a great deal of time and energy, to carry out complex cutting processes on round and square tubes required for several applications. Unverferth was forced to work with saws and machine tools—a process that involved a great deal of time and money. It was therefore necessary and natural to focus on automatic machining, which would not only reduce costs and production time, but also be able to perform very complex cuts and eliminate transfers of heavy parts from one workstation to another.
After a careful evaluation of the systems available on the market, the US company chose to purchase the FL 400 3D cutting system manufactured by TTM Laser S.p.A. "It was one of the first negotiations for the installation of our systems in the US," says Fabio Migliorati, sales manager at TTM Laser S.p.A. "Demonstrating our capabilities was not easy, due to the lack of references in the United States, but thanks to practical demonstrations conducted at our headquarters in Italy, we were able to convince the client that it was possible to accurately cut tubes and profiles to size by using our system. As a result, the client could achieve large savings due to the simplification of the processes, performed directly on a single machine, featuring considerable automation of the part loading/unloading operations, instead of the components being handled by several machine tools. The great accuracy with which these processes are carried out results in a considerable reduction in the times required for subsequent component assembly."
The company also pointed out that using a tube and bar laser cutting system could therefore improve just-in-time production, putting the company in a position to meet the related and increasingly growing demands of its customers. Another great advantage was the improved use of the production area, limiting the extension of the intermediate component warehouses during processing.
Let's cut it long
The FL 400 3D is an automatic system for cutting tubular structures with diameters up to 406mm and lengths up to 12.5m (FIGURE 3), which are required for manufacturing the wide range of systems for agricultural machinery made by Unverferth. The US company needed to cut tubular parts with a maximum size of 350 × 200mm, with very different sections, says Migliorati.
"The maximum thickness of these carbon steel components was approximately 20mm. For this reason, we provided a machine capable of cutting tubes with diameters ranging from 40mm up to 406mm and any type of open profile within these circumferences. The maximum capacity on the panel is 300 × 300mm. The tubular parts can be loaded through bundle loading (for components with a diameter below 254mm), or chain loading with V-shaped handling supports. The system features chain unloading. The maximum length of the processed tubular parts is 12.5m, while the minimum length is 3050mm. The load capacity of our loading and cutting systems is 140Kg/m. The system is equipped with a 4kW CO2 laser."
A great advantage of the FL systems made by TTM Laser is that they use four self-centering mobile chucks, which alternatively act as supports for the tubes during the loading or unloading process. This configuration significantly increases productivity (reducing downtime) and the accuracy of automatic processing. The mandrels are equipped with the special floating mandrel chuck system (FMS) feature, which is able to compensate for irregularities in the trajectory of the tubes being processed, letting the external mandrels rotate eccentrically compared to the theoretical center of rotation of the tube. The system is able to perform three-dimensional cuts thanks to the movement of the cutting head (with the rotation A-axis up to 360° along the transverse Y-axis and the continuous rotation C-axis around the vertical Z-axis), which is equipped, in its end part, with a capacitive sensor for the precise control of the distance from the surface of the tubular component. The system is also equipped with dimensional control devices for checking the length of the tube at the time of loading, its orientation, and section.
Conquering America
How did the company from Brescia manage to get itself noticed by the American agricultural machinery manufacturing firm, without having any experience in the US market?
"It all started with the collaboration between TTM Laser and ITEC (Innovative Tube Equipment Corp.), which, in a very short time, has already been involved in the installation of the first FL-400 and the sale of three TTM laser systems, representing the full range of FL type machines for tube processing, currently produced by the company from Brescia," says Migliorati. "ITEC, which represents other companies (some of which are in Brescia) operating in the field of tube processing, allowed us to access this important market—which is currently among the most promising ones—in the best way possible. ITEC also provides after-sales support for the machines sold. Finding this distributor greatly facilitated the task of interacting with the American industrial world. We were and we are ready with our solutions, but we needed a suitable and reliable local partner."
"During the technical meetings, the Unverferth managers saw the list of our many installations carried out in 14 years of business and found that TTM is the manufacturer of the largest tube laser cutting systems in the world. From this, they received confirmation of our great experience with specialization in customer oriented solutions, made to solve the problems of our customers practically and efficiently," concludes Migliorati.
DR. ANTONIO VENDRAMINI([email protected]) is a well-known international consultant on industrial laser material processing, a prolific author, and a periodic contributor to Industrial Laser Solutions. His company, Lasertec s.a.s, is located in Segrate, Italy—near Milan.