HIGH PERFORMANCE ELECTRIC BELLING MACHINES

The need for innovative green technology in the plastic pipe production industry capable of guaranteeing high performance, process flexibility and ease of use while allowing reduced energy consumption, has become increasingly pressing and has had a marked influence on the design of the various types of extrusion line machinery, including belling machines.

SICA, a specialized manufacturer of downstream equipment in pipe extrusion lines and keenly aware of the factors outlined above, was the first manufacturer to offer belling machines with an electromechanically operated socket forming unit in place of the conventional hydraulic and pneumatic solutions. The decision to use electrical technology produced several benefits: highly dynamic operation, low noise levels, exceptional precision and repeatability of positioning, total real-time control of process parameters in terms of working strokes and speeds, which is important especially for belling machines that were originally pneumatically operated.

It is very important to notice that no more hydraulic system means a complete transformation and improvement of the production process, thanks to:

• elimination of the functional problems associated with oil, as the temperature-related viscosity variations can affect the response of the regulating system;
• elimination of problems associated with the physical presence of oil which, in the event of leaks, the machine and the surrounding work area become dirty and unsafe for operators, producing a slipping and falling hazard;
• elimination of the environmental problems associated with hydraulic technology, by achieving lower noise levels typically associated with electrical technology and dispensing with the need to dispose of waste hydraulic fluid;
• significantly lower energy consumption, strictly related to the socket forming cycle.

The market responded positively to SICA’s newly introduced “Unibell” electric belling machines for PVC-U pipe diameters up to 200 mm and 250 mm. The Unibell belling machines heat the pipe by means of short wave IR heating elements (called IR-SW ovens, or simply “short wave ovens”) that maximize heating efficiency thanks to accurately defined oven geometry, precise distribution of the heating elements, and structural and electrical configuration of each heating element in relation to the specific plastic material to be heated. The many benefits of this system include lower effective energy consumption, compared to the one of the conventional heating systems, because the heating elements operate exclusively during the heating stage and for the time strictly necessary for the pipe to reach the required final thermal conditions. Instead, in conventional ovens, only a minimal part of the energy consumed is used to actually heating the pipe, while the remainder is used to keep the oven at its working temperature or it is simply lost in the environment. With sales of around sixty Unibell models in the past two years, the positive response from the market led SICA to proceed in this line of development and devote more and more resources both to the optimization of electrical technology applied to plastic pipe thermoforming operations and to the increasing of efficiency and reliability of the process.

Electrically powered thermoforming solutions have also been extended to our Unibell 400 range (for PVC-U pipes up to 400 mm in diameter), to belling machines for PP pipes up to 200 mm in diameter (Everbell) and to Multibell 110 Rieber belling machines, designed for Rieber system multisocketing on PVC-U pipes of up to 110 mm in diameter.

SICA’s decision to invest in these new technologies encourages not only a regard for the environment, it also leads to a reduction of pipe production costs, thus allowing faster returns on capital expenditure.