Category: Engineering

Press brake

Press brake

Press brake

10/07/16

“How can we using machines to bend metal to a specified shape?”

 

Metal is one of the most omnipresent materials used by humanity. However, before it can be used, it must be bent. And not only that, but to suit the quantity of our civilization’s needs, we must do it on an industrial scale. So, how can we accomplish this? Well, what if we were to use a machine dedicated to bending metal? This is the operating principle behind a Press brake. Press brakes work as follows. The machine will have two main components,  a platform for the sheet of metal to rest upon, and a brake that is used to bend the metal. The brake is powered by a servomotor. When activated, the brake will be lowered and apply a pressure to bend the sheet of metal into the user’s specifications. The platform will then move the sheet of metal along, to repeat the process to create a piece of metal designed to the user’s specifications. Press brakes can make all sorts of metals such as cold-formed steel.

Turbogenerators

Turbogenerators

Turbogenerators

10/09/16

“How can we use turbines for generating power?”
Turbines are excellent machines for extracting power. However, how can we use this knowledge to further apply it to generate large amounts of electric power? Well, let’s think about it. We know that turbines are able to produce mechanical energy when a fluid passes through their blades. And we also know that we can convert mechanical to electrical energy through the use of electric generators. So what if we hooked up a turbine to an electric generator? With this set-up, we would be able to extract large amounts of electric power. Due to the usefulness of such a contraption, it has become the operating principle behind wind turbines and hydroelectric power plants

Normal stress

Normal stress

Normal stress

10/08/16

“What happens when stress acts upon an area parallel to the axis of an object?”
The concept of stress is one of the premier foundations of all of engineering science. So, what happens when a stress is applied to an area that is parallel to the axis of the object? Well, this type of action is very simple. Since all of the stress acts through the axis of an object, the only deformations will be parallel to the axis as well. This type of stress would cause tensile or compressive deformations (depending on the direction and strength of materials). Scientists and Engineers have termed this phenomena normal stress. You can find the magnitude of normal stress very simply, as the stress is just the force distributed over the area that it is acting upon (we can represent this symbolically with the equation (sigma)=F/A, with being (sigma) the stress, F being the force, and A being the geometric area)

Eccentric loads

Eccentric loads

Eccentric loads

10/07/16

“What happens when a non-axial load occurs on a column?”

 

When working with  columns, we often have to analyze loads that impinge on the structure. However, what happens when a load acts in a direction not parallel to the axis? Well, what will happen is that the strength of the material will not be completely able to resist the force, thereby resulting in bending. Engineers have termed this type of load an eccentric load.

Cold formed steel

Cold formed steel

Cold formed steel

10/06/16

“Can we ever find a replacement for wood in construction”

 

Humanity is running into a problem. Wood, one of the most used materials in construction, is being depleted an exponential rate. Sooner or later, we must find a substitute for our needs. But what can possibly replace something as unanimous as wood? Well, luckily for us, engineers have already come up with another innovative solution, cold formed steel. But what exactly makes this material so special? Well, it all has to do with the fabrication process. Most steel is manufacturing using the hot formed procedure, in which the steel geometry is formed by being push baked at high temperatures. However, cold-formed steel gets it’s name due to the fact that is formed at room temperature. This greatly increases the yield strength of cold formed steel, makes it lighter in weight, smoothens its topology, and makes it more precise for detailing. But most importantly, cold formed steel is actually a recyclable material! And not only this, but it is also cheaper than lumber! Add on the fact that with steel you won’t have to worry about termites or rot, ad you’ve got yourself one amazing deal. In summation, cold formed steel is the way of the future, and it holds nearly limitless applications for future construction.

Shock absorbers

Shock absorbers

Shock absorbers

09/26/16

“How can we stop unexpected vibration from occurring?”

 

When working as an engineer, one has to look out for many unexpected vibrations occurring when designing a machine. With this in mind, how can make a system to integrate and solve this problem? Well, lets think about it for a moment. We know that vibrations have kinetic motion, which means that they have energy associated with them. And we also know that we can transfer this energy into other forms such as heat. So how about we create a device that transfers this vibrational energy into other forms of energy? This is the operating function behind a shock absorber. Shock absorbers work as follows. When a shock occurs to a machine, springs are attached to the part to absorb this energy and become compressed. Since this compression will store unbalanced potential energy, it must release itself. In order to prevent all of the energy from spilling out, the shock absorbers will now come into play. The shock absorbers will be constructed as a piston with oil in a tube, all inside of the spring. As the spring moves, it will cause a force on the piston, which will in turn cause oil to be forced through tiny holes in the piston that will precisely control the level of resistance to motion, therefore transferring much of the enegry in to heat. Automobiles make great use of shock absorbers, where they control the up and down motion of a wheels vehicles.

Screw thread

Screw thread

Screw thread

09/24/16

“What do those grooves on screws do?”

 

Have you ever wondered what those helical grooves on screws do? I mean, they need to have some sort of purpose, or else why would have mechanical engineers even have included them. Well, believe it or not, the functions of these groves, usually termed screw threads, is to convert between rotational and linear force, therefore enabling the entire operation of a screw!  This is as a result of the screw thread helical geometry, since the thread both wraps around and along cylinder, a rotation against object will cause it to be pushed into the object. The power of screw threads are contingent upon how close the grooves are to each other (called the pitch) and the diameter of the grooves (called the lead). When the lead undergoes a full rotation, the screw will move the size of the lead. Because of these properties are so important to functioning, screws are classified by the size of their pitch and lead.

Washers

Washers

Washers

09/23/16

“How can we distribute the loads of threaded fasteners in a simple way?”

 
When working in engineering, we often have to consider how the loads of threaded fasteners such as a nut will impact a project. Often times, these parts will cause damage onto surrounding objects due to their threaded nature. So, how could we prevent such problems from happening without having to add too much complexity to the system? Well, let’s use our engineering mindset to think about it for a moment. If we do some research, we can find out that circular geometries are superb ways to safely distribute a load due to their symmetric nature. Also, since nuts are usually on the very small scale, we don’t have to have too much weight to absorb the resulting load. So what if we were to create thin, ring-like materials to cover up the burden resulting from the fastener? This is the exact idea behind a very common piece used in engineering called a washer. Washers can be not only be used to intake loads from a fastener, but can also be used  spacers, springs, locking devices,  and vibration reducers. Different sizes of washers can be identified by the size of their inner hole and their outer diameter. All in all, washers are another example of the ingenuity of the human species.

Telescoping expansion joint

Telescoping expansion joint

Telescoping expansion joint

09/22/16

 

“How can we implement an expansion joint for tubular geometries?”

Expansion joints are very useful devices. However, how can we create affordable versions to implement on tubular geometries such as in pipes? First of all, let’s look at the problem at hand. Thermal expansion causes a material to change it’s size depending upon the surrounding temperature, and as such there needs to be “breath gaps” to ensure that a structure will not collapse. However, using something like a plaster or a soft filling will not be strong enough to sustain the expected pressures on a pipe, and having loose material might cause a leakage into the fluid flow. Therefore, we will have to think of an adjustable solid part. Well, how about we take some design inspiration from one of humanity’s greatest achievements, the telescope. Part of what makes telescopes the machines they are is the fact that they have a telescoping build, which means that solid parts are made so that they can slide past each other. Now, how about we take this mechanism and apply it to our thermal expansion joints?

 

Well, what we could do is have two concentric expansion tubes, one with a larger tube and the other with a smaller one. The smaller diameter tube will connect to the two joints of the mechanism, and will expand and contract upon need. The larger diameter tube will act as a fixed support in order to center the smaller diameter tube, and as such have a smaller diameter. You can analogize the larger diameter tubes as being like the “braces” of the smaller diameter tube. O-rings are often used to seal these parts to ensure that all operations are smooth. This layout is known as a telescoping expansion joint. Telescoping expansion joints are very useful due to their simple yet effective design, and the fact that they can be curated for tubular geometries.