Termoventilmec started life as the brainchild of the Benvenuti brothers in 1951 in Treviso. In those days, the company, known today as TVM, supplied galvanised ducting for suction systems for flour mills for the food industry. In 1955, it spread its technology into the wood, mechanical and footwear industries and today 70% of its turnover is in the wood processing industry and 50% is in the panel manufacturing sector. Recycling of plastic, paper, rubber and other areas where there is airborne pollution make up the rest of the company's sales. The current managing director, Livio Zaros, joined the company in 1970 and in 2003 he oversaw the moving of the business into brand new purpose-designed offices and factory in Spresiano, not far from the original location and to the north of Treviso. It is 25km from Venice airport. "We design, manufacture, install and commission machinery and systems for the extraction of dust, chips, trim materials or bark and filter the air, offering high- and medium-pressure conveying lines," explained Mr Zaros. Whilst the factory stocks a number of components common to most of its complete systems, all projects are custom-made in the factory to customers' specific requirements. The process starts from flat galvanised or black steel plate and sheet, which is cut with a plasma cutter and made into components for TVM's systems. But it doesn't end with ducting. Silos, cyclones, cyclone filters and radial fans are all made on site in Spresiano. Unloading systems for silos are also offered, in chain or screw type, and medium or small crushing machines for wood waste are available, although these are mainly supplied to the furniture industry. The company also designs and supplies rotary blowers for high-pressure conveying lines. A major change in the requirements for TVM's type of products came into force in 2003 with the implementation of the ATEX regulations. These set norms for explosion resistance in all of the equipment which TVM manufactures - and challenges for the company's designers as the entire systems had to be reinforced to meet the standards. "We had to redesign all our products - fans, bag filters, rotary valves, everything, to meet the new norms concerning elastic resistance, plastic resistance and we had to pressure-test everything to destruction," said Mr Zaros. "We had to use special software developed by NASA in the US and we invested a lot of money in this. "This may seem like a relatively low-tech industry, but to design a safe, effective filter system is not easy. It is also not sufficient to check each component, but you must check the complete system with all components from all suppliers including spark detection/extinguishing, suppressors, control units, everything. We now know the exact limits of our products in every application." While the cost of compliance with ATEX regulations is considerable, as Mr Zaros pointed out, an explosion has the potential for enormous and very expensive damage. However, Mr Zaros acknowledged that some potential customers look only in the short-term - at the price. Rotary valves for low, medium or high pressure are designed in-house and built up from steel plates in the workshops, including the radial fans themselves. These are constructed from stainless steel when they are to be used in wet conditions, such as for wet chip transport in a panel mill. Fan impellers of course have to be accurately balanced and this is carried out on an electronic machine in the factory. "In positive pressure, we only make open fans because they do not get blocked by plastic bags, paper and other foreign material which may get sucked into the line," said Mr Zaros, explaining that in negative pressure situations where the material to be transported does not pass the fan, an ordinary fan can be used. The company manufactures four families of self-cleaning bag filters - two positive and two negative pressure. Cleaning is by compressed air pulses and reverse air pulses. The central section for bag filters is reinforced to ATEX norms. For those panel mills with pre-2003 bag filter systems, all is not lost. TVM can supply this central section, with diaphragms and explosion vents, to be inserted between the head and the hopper to upgrade the plant to meet current standards. For new bag filters, a different system is used, employing ATEX-certified vents. The company supplies its systems directly to the clients, or as part of the supply contract of other engineering companies - for instance Pal srl, which uses TVM equipment on its wood preparation lines. The woodyard is another area of application for TVM products - where wet bark needs to be transported for example. Having extracted all this wood 'waste', TVM can also offer a pellet plant to make use of it. Launched at the Xylexpo exhibition in Milan in May, the pellet press produces wood pellets from your wood 'waste', which can be burned to provide energy. In spite of the general global recession in recent years, Mr Zaros said TVM has seen demand for new plants maintaining an even keel and that the company has prospered.