Maintaining national rail infrastructures is an extraordinarily difficult task. The U.S. rail network comprises almost 140,000 miles of track, encompassing freight, intercity, and passenger railroads. Each of these sees intensive daily use. As much as five million tons of freight and around 85,000 passengers are transported by rail every single day. That volume of traffic puts a significant strain on track components.


Why Use Spark Blankets?

A spark blanket is a type of fabricated part used in rail grinding, welding, and maintenance. Engineers may use spark blankets at multiple touchpoints from initial installation to eventual replacement of broken rails.  Spark blankets are also instrumental in reducing the risk of wildfire caused by the sparks created during the rail grinding process, and are key for regular maintenance to prevent environmental damage like pull aparts and sun kinks.

Understanding Rail Maintenance

Day-to-day upkeep is essential to ensuring that train operations continuously run smoothly and safely. An enduring issue in rail maintenance is the effect of seasonal variations; temperature fluctuations, and so on. Most railways today comprise continuous welded rail (CWR) with significantly fewer joints than conventional tracks. These are much easier to maintain – provided the CWR has been laid and fused at a stress-free temperature (SFT) within an accepted seasonal range. Tracks that have been installed outside that range will be prone to thermally-induced distortion caused by seasonal variations in temperature.

Extreme heat can cause steel tracks to expand which may ultimately lead to buckling (sun kinks). Conversely, extreme cold will lead to contraction which can cause embrittlement and cracking. To prevent costly temperature-related faults, rail engineers stress track components by heating them to their SFT. Plain line rails may be hydraulically stretched, but this is impossible for crossings and switches.

Rail heating is a viable option for plain line tracks, switches, and connectors. But elevating the track temperature to standard U.S. SFTs of 35—43C requires high-performance insulation capable of mitigating ambient temperatures. This is one of the key applications of fabricated spark blankets. Engineered for maximum durability in the field, spark blankets effectively contain and direct heat generated by stressing equipment into track components. Stressing segments of track, whether old or new, can subsequently be carried out faster and more efficiently, reducing downtime.

Spark Blankets from Mid-Mountain

At Mid-Mountain Materials, Inc., we have developed a wide range of high-performance fabricated parts based on precision thermal materials. We supply stress relieving blankets for rail maintenance and spark blankets for heavy duty track maintenance applications like welding and grinding. Want to learn more? Contact a member of the team today.