Archive for November, 2009

RoHS-compliant TPEs provide high level of flame retardance

Friday, November 13th, 2009

A new series of Elexar thermoplastic elastomer (TPE) compounds for wire and cable and molded products provides a combination of RoHS compliance, UL-V0 flame retardance and good performance over a wide range of end use conditions.

The Elexar High-Performance FR series includes six grades, with Shore A hardness ranging from 58 to 85, upper use temperature from 105 to 125 ºC., low-temperature flexibility down to -50 °C., very good UV resistance, and good oil resistance. For applications where appearance is critical, the compounds provide good colorability and non-blooming surfaces.

Elexar HPFR compounds embody a combination of end-use performance and compliance with the stringent standards required in the global marketplace. According to the company, conventional flame retardant TPEs not only fail to comply with the RoHS directives but are more limited in terms of flame test ratings and service temperatures. In addition, their flame retardant formulations often present the problem of blooming or surface staining.

The Elexar high-performance FR compounds are used in extrusion applications like insulation and jacketing for automation and control cables, fiber optic cables, specialty low-voltage power cables, appliance wire and flexible cord.

Heater Platen Delivers Faster Thermoforming Cycles

Friday, November 13th, 2009

A new tool-specific heater platen developed by GN Thermoforming Equipment provides higher output, better product clarity, and quicker tool changeovers for large-volume applications. It is the first of its kind for contact-heat, cut-in-place thermoforming machines, according to the company.

Depending on product design, the dedicated heater platen can reduce cycle time by 20% to 30%. In addition, greater product clarity is achieved and material distribution is more consistent due to the quicker forming times. The new platen system is designed to match a specific tool by pre-engineering heater and air channel locations within the platen to optimize the process.

Instead of heating the whole plate, now only dedicated areas are heated; and the same goes for the forming air. Each dedicated heater platen has a specific cut plate that matches the design of the tool cutting die layout. An air channel is located in the platen within 1 mm of where the cutting die touches the cutting plate, allowing a high volume of forming air to reach each cavity.  The channel provides significantly more air volume than the 0.4-mm holes located within the die perimeter on a standard GN Thermoforming cut plate. A retrofittable locating feature on the mold carrier beam keeps the heater platen accurately lined up with the tool. An aluminum insert within the die perimeter is micro drilled for venting and anodized for durability. It provides more consistent heating and a clearer product.
With its new dedicated heater platen, GN Thermoforming has test run 16-mil- thick APET sheet at 26 cycles/min. for production of 40-mm-high product. This is significantly faster than the 20 cycles/min rate on a traditional GN thermoformer.

While the tool-specific heater platen adds $12,000-$18,000 per tool set, the investment can be easily recouped due to the high production efficiencies, according to the company. The new product is being used in for food packaging applications.