Honeycomb-Based Sandwich Panel Reinforcements
Sandwich panels with honeycomb cores are a very lightweight approach to creating durable rolling stock interiors, and are used for doors, partition separators, and floors. Many panels have a structural component to increase their functionality, but due to the lightweight nature of their build-up, attachments that can carry loads cannot be created easily. Local reinforcements are created by filling the honeycomb cores with a potting. L&L products produce lightweight yet strong potting materials allowing sustainable attachment points
Unfortunately, honeycomb-based sandwich panels do not always come in the dimensions required for final application, and several panels need to be connected while maintaining a strong connection. L&L Core splice materials cure smoothly and require very limited post processing.
Honeycomb-based sandwich panels also require a solid close-off for the edges. L&L has developed a technology like 2K adhesive bonding, where the material is mixed by a nozzle and pumped smoothly onto the edge of the panel, where it can be smoothened/sculpted easily and cures rapidly. Compared to currently used manual mixing of such materials and their manual application in the edges, this technology is reproducible and results in much faster production processes. Due to the lower manual work, quality of the application is improved.
All products comply to the latest EN45545 – 2 FST and flame requirements.
Key solutions include:
- Low weight
- High strength and durability
- Increased safety (fire protection)
- Easy application, highly reproducible quality with reduced waste
The ignition and spread of fire in rail applications is considered one of the most important design problems rolling stock designers and producers need to deal with. It takes a significant amount of time to stop a running train and evacuate its passengers. This is even more difficult in tunnels and for metro applications. For this reason, rail engineers are always actively looking for materials that are flame-retardant in nature, but also able to reduce the spread of flames when ignition has already taken place.
L&L Products have designed a lightweight, extremely effective fire-blocking layer as part of its DECI-TEX® FST product line. This product is a fiber-based, non-woven layer, with weight as low as 135 grams/m2 that has passed even the most stringent Aerospace test requirements, like the oil-burning test. The product can be tailored to match rolling stock producer needs for sound and thermal insulation by using a layer approach or through adjustments of layer height and density. It is available in large-length rolls, 2 – 2.5 meters wide, as well as cut to size, and can easily be shaped in 2D or 3D forms without losing any of its properties. Since the layer is easy to cut with conventional industrial scissors, size adjustments can be made during assembly.
Key solutions include:
- Complies to all relevant flame-blocking and FST requirements in rail applications: E/I 30 or 45 are possible (EN45545 – 3)
- Survives temperatures up to 1150° C
- Safe to handle and work with
- No unnecessary waste, material available on rolls and cut to size
- Tunable thermal and sound insulation properties
Key applications include:
- Wagon insulation (side walls, roof, floor)
- Locomotive insulation (sound/fire)
- Underfloor fire protection