Tunnels with overhead conveyor are characterised by their versatility, high productivity, ease of management, efficiency and treatment quality. They also stand out for the ability to treat large and heavy parts. They can be configured for simple processes or for very complex ones which require the use of a high number of different treatment phases. The tunnels with overhead conveyor call for the parts to be hung on bars provided with "hooks" which are in turn attached to the conveyor. These bars with hooks can be fixed or rotating depending on the complexity of the geometry of the parts to be treated, or depending on the requirements of any downstream processing. The great versatility of the overhead conveyor chain transport system allows to set up treatment tunnel and entire process lines as you wish; as a result the tunnel may have rectilinear, horseshoe or L-shaped forms, etc. The same overhead chain conveyor can transport parts over very long distances and can therefore serve various work islands without the pieces being handled, using double-rail overhead conveyors; the line can accommodate various loading and unloading areas or part storage warehouses etc. Typical applications of these systems cover pre-treatment before painting, washing of sheared and bent products, small-scale fabrication, engine casings, pump housings, filter housings before mounting, parts after polishing, such as stainless steel sinks, stainless steel trays and stainless steel tanks, etc.

Time-set pallet systems allow to treat one or more pieces at a time in a fixed "indexed" position, with loading and unloading, manually or automatically using a robot, at the same point or at two opposite points. These machines are equipped with a transport system capable of stopping the pallets holding the pieces in defined positions ensuring high precision: this features allows the performance of targeted treatment with guaranteed results on parts with complex geometries, with blind holes, ducts of small diameter, etc. For this purpose, in defined positions, the washing is performed with calibrated interchangeable screens or with anthropomorphic robots; the choice of design of the two solutions is dictated by the number of parts with different geometries that will be processed; obviously with a large number of parts the robot solution would be the preferred option due to its versatility and protecting the investment made. With this type of system even very high working pressures, if required, may be used, therefore allowing a washing with a deburring action. With the need for accurate deburring and not only hanging burrs, these machines are suitable for having stations for processing mechanic burrs with abrasive disc brushes, duct cleaners and tools.

Machines with motorised roller conveyor systems, despite being used with very heavy pieces and therefore not able to be transported by conventional conveyors, are actually ideal for treating flat sheets. In limited spaces they are able to treat solid or perforated metal sheets, both flat sheets or continuous "colis" tape, with speeds up to 50 m/minute. Their main features lies in the transportation system consisting of a series of motorised rollers positioned on the bottom of the conveyor, which can also be in rubber, on which the metal sheets advance continuously; above this are used pressure, wringer, containment and contrast rollers. The treatment is carried out by close spraying phases and mechanical brushing, the combination of which allows to achieve remarkable washing results in very short times. Wringing at the exit point of each phase eliminates all kinds of residues and prepares it for the drying phase. Hot air blown at high speed and special absorber rollers are used in the drying phase. These machines are typically used for: washing coils after flattening, washing aluminium coils after mechanical etching and washing perforated metal sheets after cutting.