Archive for December, 2008

Ionisers Eliminate Static Packing Problem

Wednesday, December 10th, 2008

When adhesives, coatings and speciality films manufacturer Bemis ran into difficulties packing one of its advanced thermoplastic polyurethane films for use in the textiles industry, a pair of ionisers from static control specialist TBA Electro Conductive Products (ECP) sorted out the problem. Mark Lineker, TBA ECP’s static products manager explains.

Bemis is recognised worldwide as a technology leader in providing adhesives, coatings and speciality films for a myriad of industries and applications. From the automotive and aerospace industries, through textiles and building construction to woodwork in modern kitchen and bedroom furniture, Bemis’s diverse range of products can be found.

In the apparel industry, Bemis supplies a multitude of the world’s leading clothing manufacturers with a diverse range of materials from decorative emblems for sportswear to Sewfree� film adhesives for bonded garments that eliminate stitching. One of these materials, Clarense�, is a strong, lightweight, clear elastic film that was developed as a superior alternative to traditional elastics.

Considered to be at the cutting edge of apparel technology, Clarense is a versatile thermoplastic polyurethane film that can be used as an elastic or decorative component. As an elastic, it can improve the wear and fit of garments by being sewn into critical seams for reinforcement. Clarense features superior strength and elasticity, allowing for greater design flexibility because it is thinner than traditional woven or knitted elastics yet offering the elasticity that fabric tapes lack. In addition, being made from polyurethane, Clarense doesn’t cause irritation if it comes into contact with the wearer’s skin.

Bemis offers Clarense in various thicknesses and widths up to 142cm and it was in the process of producing thin strips that a problem developed. Bemis developed machinery to produce very narrow strips (3 to 5mm wide, 0.1 to 0.15mm thick) by slitting sheets of the stretchy elastic. At these sizes, the strips are very light and after running over rollers, the finished strips are dropped into plastic bags ready for delivery to garment makers’ production lines. However, it was found that the strips were becoming charged with static as they ran over the rollers and this was causing them to become tangled and stick to the plastic bags as they were being packed.

The result was an unacceptable reject rate from customers and a solution was urgently needed.

Terry Davey, Bemis’s Technical Services Manager comments, “The problem was fairly quickly diagnosed as being caused by build up of static due to the thin films running over the rollers so we needed to find some way of eliminating that situation.”

“Following a brief search on the Internet, we located TBA ECP as a potential supplier and they reacted promptly to our request. The company suggested using ionisation to eliminate the build up of static on the films and made some suggestions as to where we could mount the ion bars. Through some experimentation, we found the best positions on the slitting machine and have succeeded in eliminating the static. Consequently, we have seen a significant reduction in the number of rejects on this product – in fact, rejections due to the static problem have been eliminated completely.”

He concluded, “We also found that eliminating the static problem had a spin off benefit in that we were able to significantly increase the speed of the machine and thus improve productivity.”

TBA ECP’s static eliminator bars are designed for use in a wide range of industries where static is a problem.

Extruded in white FR ABS for strength and rigidity, the ion bar provides powerful long-range ionisation. Its “tear-drop” profile minimises air turbulence and enhances stiffness along the length of the bar. It also eliminates the dust traps that are so often a problem for similar equipment.

Ion bars provide a non-contact solution to the problems caused by electrostatic fields within electronics EPAs (electrostatic protection areas), cleanrooms and other industrial applications where static is a problem. Extremely effective in reducing quality defects resulting from ESD, the ion bars are ideal as part of an integrated electrostatic control system as described in BS IEC 61340-5-1 PT 1:1998.

Quick and easy to install, the ion bars complement TBA ECP’s extensive range of static control products that includes flooring, ionisers, packaging and storage systems, grounding products, work surfaces and workstations, instrumentation, coatings and complementary services such as quality audits. The company is capable of delivering floor-to-ceiling static control solutions encompassing everything required in ESD protection areas.

TBA Electro Conductive Products is a specialist manufacturer of high quality electro static protection (ESP) and electro magnetic interference (EMI) shielding products.

Cost Effective Vents For EMI/RFI Shielding

Monday, December 1st, 2008

Shielding vents provide effective shielding against electromagnetic and radio frequency interference EMI/RFI).

More than 80 standard sizes of vents are in the TBAECP range of EMI/RFI shielding. Designed as simple screw on panels, ECP 8000 series aluminium shielding vents are available with several styles of frame and allow designers and OEMs an easy solution for protecting airflow or lighting apertures. According to TBA ECP, the standard sizes are pre-tooled with either drilled holes or threaded inserts provided for fixing, enabling users to avoid the cost of special tooling that would be needed for a custom design. With 80-plus standard versions, users will be able to closely match their requirements by designing their aperture to fit the shielded vents available rather than designing a custom vent to fit the aperture.

Standard construction of all vents comprises an aluminium honeycomb in two 6.3mm thick layers with a 3mm cell diameter, laminated in a cross cell construction and contained in a peripheral extruded aluminium frame. Optional frame styles are flat or with groove depending on type of seal required.

A variety of finishes is available encompassing chromate, tin and nickel for standard honeycomb versions, providing attenuation levels from 60dB typical for chromate up to 115dB typical for nickel (1GHz plane wave). A chromate finish with cross cell honeycomb version provides 90dB typical attenuation (1GHz plane wave).

Fan apertures can be shielded with the ECP 8200 series standard shielded vents where enclosures require EMI shielding combined with maximum airflow. These vents feature a 6.4mm single honeycomb layer with 1.6 or 3mm diameter cells held in pre-drilled rigid aluminium frames with a conductive chromate finish. Five sizes are available to match popular standard fan sizes and these vents can be supplied with optional dust screens if required. Fan vents are also supplied fitted with the company’s ECP 625 beryllium copper gaskets as standard.

ECP 8300 series Quiet Vents are available in no fewer than 66 sizes and deliver an excellent low cost solution to the demanding cooling requirements of modern electronic equipment. The honeycomb panels feature rigid, extruded aluminium frames with optional captive fasteners or through-holes. Quiet Vents are supplied as standard with composite knitted gaskets that combine a neoprene gasket with wire mesh to provide efficient EMI/RFI shielding between the frame and mounting surface.

http://www.tbaecp.co.uk

TBA Electro Conductive Products Ltd.
Unit 3
Transpennine Trading Estate
Gorrells Way
Rochdale
Lancashire
England
OL11 2PX
UK
Lancashire OL12 7EY, UK
Tel: +44 (0)1706 647718
Fax: +44 (0)1706 646170