Bernd Fischer and Winfried Schaefer of Roth Composite Machinery is a powerful new name in pleating and coating equipment for filter media.
More companies, more papers and more visitor footfall proved that Filtech is now well established as the comprehensive platform for the filtration industry in Europe – and growing all the time
By Adrian Wilson, European Correspondent
Pleating and nanofibers
Media manufacturers continue to develop new ways of making filters even more effective and the use of advanced pleating methods and nanofiber layers and coatings are two notable ongoing trends.
Ahlstrom, for example, has developed its NanoPulse nanofiber-coated cellulose and synthetic media for reverse-pulse gas turbine and industrial air applications.
Designed to remove high amounts of sub-micron sized contaminants, the nanofiber layer is securely adhered on the upstream side of the media to assure optimal dust cake release during reverse pulse cleaning. A deep grove with good shape retention helps to separate the media’s pleats, with smooth pleating assured even on rotor machines as a result of the strong and robust engineered base fabric.
A new name in nanofibers is Nxtgen, of Claremore, Oklahoma, which formed three years ago to meet a gap in the market and is now securing strategic partnerships with organizations in a variety of industries.
“We are first and foremost a high volume nanofiber manufacturer,” explained Nxtgen General Manager, Andy McDowell. “We saw the mismatch between the production rates industries would need and what was available, which led us to design and develop our own process for nanofiber production which we call HYPR – high yield production rate – spinning. With our method there is virtually zero polymer waste, which means no down time for machine spinning. We are producing at rates of up to 100 meters a minute, in excess of ten times more than other commercial nanofiber methods on the market, while still producing true nanofibers.”
Most applications, he added, require specialty polymer blends and fiber technologies.
“So we felt it necessary to design a system that could be rapidly tailored for unique products. We produce bicomponent nanofibers, gradient density and diameter nanofiber matrixes, multi-polymer nanofiber composites and even colored nanofibers. Our system makes this very easy and switching between products literally takes only a few minutes. We can produce nanofibers from practically any polymer and adhere to a vast array of carrier media where necessary.”
Porex, based in Fairburn, Georgia, introduced its tubular 20nm Ultrafilter for demanding applications such as wafer grinding, where fine abrasive silicon particles and colloidal silica gel particles range from 20-50nm and are very sharp, with the ability to quickly damage many types of membrane.
“The 20nm membranes incorporate the same robust bond to the substrate as standard Porex tubular membrane filters, which are engineered for high strength and durability,” said Director of Global Business Development, Doug Frick. “This makes them the ideal choice for wafer grinding applications.”
An entirely new type of 3D woven metal media has been developed by Haver & Boecker, based in Oelde, Germany, with the assistance of the Math2Market GeoDict simulation system.
“The traditional way of designing and testing filter prototypes is costly and time consuming,” said Andreas Wiegman of Math2Market, which is based in Kaiserslauten, Germany. “This is due to the complex interplay of the material properties of the filter media, the arrangement of fibers in the medium, the physical and chemical properties of the fluid being filtered and the characteristics of the particles in the fluid. GeoDict is a modular package developed for the simulation of filtration processes and its modules help gain insights into the behavior of existing filters, and beyond that, to develop new filter media.”
Speaking at the Filtech Conference, Haver & Boecker’s Vice President of Sales, Friedrich Edelmeier, said that the company’s RPD Hiflo-S material could achieve twice the throughput volume flow for a given pore size than traditionally woven structures as a result of its 3D structure.
Separating the wires
“Using the GeoDict simulation tool to predict performance we were able to optimize the 3D structure by separating the weft wires from one another so that the number of pores is doubled over a given surface area, but the pore size remains the same,” he said. “In addition, the pore sizes can be calibrated from between five and forty microns, which means that we can now carry out a sequence of orders in a single production run. In the past, these had to be made separately.”
In addition, the flow conditions are optimized and turbulence around the filter cloth is effectively avoided.
The new filter cloth can be manufactured from standard diameter wires with a positive effect on cost. The company can now also weave special materials and is able to offer a corrosion and temperature-resistant filter cloth with pore sizes below 40 µm for the first time.
The depth structure of RPD HIFLO-S offers a high separation effect without rapid blinding. Dirt holding capacity and cleaning capability have proven to be excellent.
Efficiency and dust holding capacity are no longer the most important properties in air filtration, said Germany’s Sandler. Energy efficiency during operation of the filter plant is gaining in importance and influencing testing standards and as a result, filter media are expected to contribute to lower energy consumption.
Sandler’s new synthetic enAIRsave media combines performance and reduced energy consumption and consists of three filter layers to provide optimum dust separation, not just in the fine fiber layer, but also across the entire width of the media. The particles are primarily deposited in the coarse meltblown layer as well as the pre-filter layer. As a result, air can still flow through the filter at a relatively low pressure and, consequently, with reduced energy consumption.
Pocket filters made from sawascreen enAIRsave are self-supporting even when loaded with dust and the pockets do not sag when the air stream is cut off.
For tight spaces
Increasingly, components containing nonwoven filter media such as air cleaners and air intake systems are being required to fit into reduced spaces in commercial vehicles.
The compact design of the vehicles, additional components for comfort and exhaust gas after-treatment systems are all putting further limits on available installation space.
In response to such challenges, Mann+Hummel, headquartered in Ludwigsburg, Germany, has developed two new flexible air cleaner concepts.
With its oval-conical shape, Exalife air cleaners are ideal for narrow and flat installation behind the driver’s cabin, for example, or on top of the engine under a long hood, as is typical in US trucks. These filters also excel due to significantly lower pressure loss than air cleaners with axial-flow used for similar applications. One big advantage here is the reliable radial sealing concept familiar from round filters. Mann+Hummel already has production capabilities for these filters in place worldwide.
With the VarioPleat air cleaner, meanwhile, pleat heights of up to 300mm can be achieved with the company’s proprietary nonwoven converting manufacturing technology. This allows the filter element to be optimally adapted to the available installation space and interfering contours, such as the wheel arch.
Painless PTFE coating
Finishing machinery specialist Monforts has recently delivered a number of its latest Montex 8500TT stenters to European filter media manufacturers.
“This is the first system on which it is possible to thermally set PTFE fabrics without oil greasing in the stenter chain and in the width adjustment,” said Jürgen Hanel, the company’s head of technical textiles. “This protects workers and the environment from harmful oil vapors and keeps the filter material clean. The guarantee of reaching 320°C with a very low temperature tolerance and with an excellent housing insulation is a major advantage, so that we never reach an outside temperature over 60°C at any position.”
In addition, the Monforts’ foam padder is able to run two different foams at each side of the material.
“For nonwoven applications this is recognized as a cost effective applicator while retaining the porosity of the materials being coated,” added Area Sales Manager, Thomas Päffgen. “With the foam solution our customers save drying costs and can run at much higher production speeds compared with a liquid padder. This applicator can, after modification, also be used for thick felts and woven materials.”
The Montex 8500TT stenter is ideal for the preparation of filter materials offering a stenter frame for the drying and finishing of both woven and nonwoven, with high stretching devices in both length and weft direction up to 10,000N and at high operating temperatures up to 320°C.
There was also a strong showing at Filtech 2016 from Italian companies, including Grezzana-based Alteco, which specializes in the production of stainless steel filter housings and installations for the food and beverage, industrial, chemical and pharmaceutical sectors.
With annual sales of around €5.4 million, Alteco achieves 25% of its turnover in Italy and 70% in the rest of Europe.
The family-owned company has been processing steel since 1955 and today its main customers are cartridge and filtration unit manufacturers and dealers, in addition to installation and machinery manufacturers.
“We can comply with any customer request and have the flexibility to meet customized requests, in addition to our ready-to-use and tailor-made products,” said director Matteo Albrigi. “All of our processes are based on lean production principles.”
SIFA Technology, based in Sassoferrato, meanwhile specializes in the supply of a range of materials and provides logistics and assistance to air and liquid filter manufacturers, meeting a real need in the market.
“We focus our attention exclusively on the air and liquid filter manufacturers and avoid any contact with the final product users in order to guarantee the highest standards,” explained company chief Fabrizio Perini. “We are experts in both nonwovens and PU adhesives and how to maximize the combination of the two. We are active in 45 countries worldwide and nobody can compete with our range of products.”
Gusbi, based in Vigevano, has drawn on its long experience in turn-key plants for the footwear industry as well as the technology of the food processing industry in the development of its automatic rotary machines for the molding of air and panel filters with polyurethane seals.
Each individual station within the system can produce up to 12 filters at once, with the total output of one installed line for the automotive aftersales market being up to 1,200 pieces an hour.
“The big advantage of our system, compared to conventional manufacturing lines based on conveyor lines, is its flexibility,” said General Manager, Giancarlo Bianchi. “The filter media and frame are also welded together without adhesives, making it a very sustainable process.”
Super Spark Blocker
In steelworks, foundries and other industrial works where non-ferrous metals are processed, high temperature particles and sparks can pose problems. In filtration systems, nonwoven filter media, especially those based on polyester, can be particularly vulnerable to damage.
To combat this, Testori, based in Novate Milanese, Italy, has developed its new Super Spark Blocker range of spark resistant needlefelts.
“The felts are based on the use of a special acrylic fiber blend and available in combination with both polyester and Nomex nonwovens,” explained business developer Lorenzo Balzaretti. “As a result of their chemical composition and high limiting oxygen index – LOI – Super Spark Blocker nonwovens are capable of withstanding even continued contact with incandescent particles, preventing holes in the filter bag by acting as a shield on the surface of the felt.”
Another interesting Testori product is the Solaft StarBag, which can significantly reduce costs and solve bag house capacity problems.
The filter’s unique pleated design can double the available filter area in the same place as traditional cylindrical and oval bags. The pleats are gathered at the top snap band so that the StarBag can fit in the same cell plate hole as a standard bag and horizontal bands sewn into the felt ensure it retains its pleats for its entire service life.
In addition to its manufacturing sites in Italy for wovens, nonwovens and filter bags, Testori has operated TTL in France since 2000. TTL specializes in multi-channel bags for the primary aluminum industry and also products for filtering gas using hi-tech fibers and those for wet filtration.
Testori has recently inaugurated two new plants outside Europe – a US company in Cincinnati that produces felts, and a second in Abu Dhabi that converts products for gas and liquid filtration.
The company refers to its strategy as “going glocal” – casting a wide international net, while having local expertise on the ground in each region – an approach that chimes with many of the companies at Filtech this year.