Photo Credit http://www.huffingtonpost.com/2014/03/31/yellowstone-national-park-earthquake_n_5060314.html
The story of the Yellowstone super volcano is a relatively well-known one- although it’s most recent super-eruption was more than 640,000 years ago, the terrestrial effects are still visible today in the form of geysers and the massive caldera, measuring 30×45 miles even after being filled in by lava flow. It’s been nearly 174,000 years since the last eruption, but seismic activity and the volcano itself are still monitored around the clock, with dozens of scientists carefully observing the minute details for any sign the volcano may be preparing to erupt again. While it doesn’t seem likely that it will in the near future, new evidence has been uncovered that the hotspot responsible for creating Yellowstone, which has traveled from the southern Idaho area to its current location, was also the creator of even larger, more devastating volcanoes in the past. Continue reading
Rotary and stationary slitter blades
There are tons of “behind the scenes” technologies that are used to manufacture the products we use in our daily lives and most go unnoticed by the average Joe. Entire careers and fields of study are built around things like figuring out how to stick two things together or understanding the best way to cut something apart. For example, in the world of printing and packaging there is an essential piece of technology that makes it possible to create the books, boxes, bags and magazines we use every day. It is called the slitter blade.
Before many products are made the raw materials to make them have to be rolled up onto a large roll (think of a paper roll used to make newspapers). This roll of material is then cut into smaller rolls or strips of material that are fed into further manufacturing processes like printing. Changing these large rolls into smaller ones or strips requires special equipment the can cut it properly. That is where the slitter blade comes in.
Slitter Rewinder – Image credit: convertingcurmudgeon.com
Slitter Blades are used in machines called slitter rewinders that take the large rolls unwind them through the blades and rewind the material into smaller rolls. Blades used on this type of machine are small (approximately 2” – 6” in length or diameter depending on the geometry) and come in two general types, straight and round. These blades are single edge blades (like razor blades) but, some of these blades, used for making perforations or other intermittent cuts in the material are not a continuous blade edge. There are there are a few types of machines that use multi-edge blades (like saw blades). This type of slitter cuts the entire rolled material at once with a large blade without unwinding the roll.
Large Blade Roll Slitter Diagram. Image credit: Rollrazor.com
The single edge blades are the most common and have been used for nearly 100 years in slitter rewinders to cut rolls of material. The round blades roll against a hard roller and cut the material as it moves between the between the two. The straight blades are stationary, and the rolled material (or web) is pulled through them causing it to part and split into two smaller webs. Both versions of single edge blades are very sharp and need to be replaced often to keep the material from being ripped during slitting.
The large saw blade slitters cut the material like cutting a log. This process is very similar to how a skill saw cuts wood except it is a roll of material and not a solid piece. As the rotating blade plunges into the roll it cuts through the layers of material until it reaches the center core and a smaller roll is parted from the end.
It takes a great deal of understanding to select the correct slitter type for the product you want to cut. There are specialty blades for cutting papers, films, metals and almost any other product you can put on a roll. (yes including toilet paper.) How do you think you get that small roll the fits onto the holder in your bathroom? Or, even that roll or paper towels you have in your kitchen. At some point in the process that roll was cut using a slitter blade. Now, I bet you never thought that there was a complete industry build around the ways to cut your toilet paper, but there is.
So next time you grab that roll of aluminum foil or paper towels, take a look at the edges, and you can tell someone that that was cut using a sitter blade.
This thing is awesome. I wish I worked on this project.
There are many compelling reasons why Hybrid Cars are becoming more popular, the main ones being:
- The high price of fuel that makes most ‘normal’ cars very expensive to run
- The fact that burning fossil fuels is causing many people to think very carefully about how this might be leading to climate change due to the build-up of CO₂ in the atmosphere.
With most of the big names in the Automobile Manufacturing industry having at least one Hybrid model in their range, you might be wondering how these vehicles work, giving more mpg with lower emissions. The simple answer is that these vehicles only burn gas when they absolutely need to, so they are extremely economical to run.
How a Hybrid Automobile Works
Hybrid vehicles combine an electric motor with a gasoline engine and some other clever technologies to increase fuel economy too.
- A smaller more efficient engine can be use in Hybrid vehicles, thanks to the electric motor that provides additional power for acceleration and steep inclines. These small, lightweight engines often of Aluminum construction, make use of variable valve timing to ensure the most efficient and complete utilization of fuel.
- The electric motor can be used on its own and is the primary source of power for town and city, low-speed, stop-start driving, the situations where these motors are more efficient than gas-powered engines.
- The automatic shutoff and restart feature is also useful in stop-start driving situations. The engine is automatically switched off when the vehicle stops so that energy is not wasted with the engine idling and the vehicle is not moving. The engine automatically restarts when the accelerator pedal is depressed.
- Regenerative braking converts the energy normally wasted during braking into electricity. It is able to do this because the wheels automatically engage to a generator. By doing so, additional load is created that assists in braking but also, by driving the generator, creates converts mechanical energy to electrical energy that can be stored in the batteries for later use by the electric motor in the vehicle.
Unlike purely electric vehicles, a Hybrid car will not need ‘plugging in’ to recharge the battery. The gas-powered engine will automatically engage when batteries become depleted to a certain level. This will recharge the batteries and power the electric motor if necessary. Many people do not realize that choosing a Hybrid vehicle will not limit them to being able to find charging points or being able to charge their vehicle overnight.
Have More Questions About Hybrid Vehicles?
If you want a one-stop reference source regarding hybrid car technology, take a look at this downloadable PDF, the Master’s Thesis of Gustaf Lagunoff and entitled Automotive Hybrid Technology – Status, Function and Development Tools (http://epubl.ltu.se/1402-1617/2008/217/LTU-EX-08217-SE.pdf). It is so comprehensive that it will answer every question you could ever think of!
Getting the Max MPG out of Your Hybrid!
If you would like some tips on driving technique for Hybrid vehicles to maximize fuel economy and vehicle efficiency, Toyota have a very helpful article on their blog. You may not have a Toyota, but the tips are relevant to most vehicles and there are even some on how to get more MPG out of a conventional gas-powered vehicle! (http://blog.toyota.co.uk/hybrid-driving-technique-toyotas-top-tips-for-achieving-the-best-fuel-economy-in-your-hybrid)
Sources & Related Info:
- http://auto.howstuffworks.com/hybrid-car.htm
- https://www.fueleconomy.gov/feg/hybridtech.shtml
- http://abcnews.go.com/Technology/Hybrid/story?id=97518