Criticism / Suggestions » There exists for any rotating sh

No matter the gender Dallas Cowboys Color Rush Jerseys , we all want to stay sharp as we age. One of the biggest stressors people have about getting older is thinking about how we’ll be able to maintain our memory and more importantly, our overall function as we age, and not burden the kids. Well, it seems that once again, we’ve got a serious health concern seriously helped by regular exercise. Recent studies are showing that our memory may also depend on how fit we are physically. Here’s what that means. It is the brain’s hippocampus that is vital to certain types of memory, and like some other things, its size matters: studies have shown that a bigger hippocampus is better. Researchers have found that elderly adults who are more physically fit tend to have bigger hippocampi and better spatial memory than those who are less fit. A study published in Hippocampus journal shows that the hippocampus size in physically fit adults accounts for about 40 % of their advantage in spatial memory. Now, there are certain activities are believed to modify hippocampus size in humans; previous studies also have found that the hippocampus shrinks with age and coincides with cognitive declines at a rate that differs from person to person. In addition, earlier studies have shown that exercise increases hippocampus size and spatial memory in rodents. But most amazing is this new Hippocampus study which is the first to demonstrate that exercise can affect hippocampus size and memory in humans. The researchers found a significant association between an individual's fitness and his or her performance on certain spatial memory tests. This is pretty clinically significant because it supports the idea that your lifestyle choices and behaviors may influence brain shrinkage in old age—keeping you independent for longer! So folks, we shouldn’t have to hear it from anyone again, we just need to stay moving on a regular basis for optimal health, all around. One of the significant risks to the performance and life-cycle of a fan system is vibration of the equipment. The vibration level of a centrifugal fan will determine its mechanical condition. If the vibration is too intense then it can become serious threat to fan operation causing forced shutdown. There could be many reasons for a centrifugal fan to have vibration issues, from a simple mechanical defect such as mass unbalance to more complex shaft misalignment, bearing failures or resonance problems. A fan system requires regular checking to determine the right acceptance limits of vibration. If the vibration is above acceptance level, then the fan system needs an analysis to look into the problem for rectification.

Rotating devices such as fan systems suffer unequal distribution of mass due to their mechanical design, installation and operating conditions. Centrifugal fans can have some minor imperfections that can cause vibration to the equipment. Even small changes such as debris buildup, rotating part distortion or blockage can induce imbalance in the system leading to problems in fan components. Vibration is always present as a result of one or more exciting forces. If there are no exciting forces, there will be no vibration. The cause of vibration in a rotating equipment may be due to : 1) Unbalance 2) Looseness of parts 3) Misalignment 4) Bend shaft 5) Bend bearing, gear or belts 6) Weak support.

Mechanically loose connections

Centrifugal fans can have loose mechanical connections between bearing housing & pedestals or between the fan rotor & shaft. When centrifugal fans have higher rotation speeds, they exert force on the bearings due to unequal distribution of weight. In other cases, the fan may experience loosening of the setscrews due to fretting or corrosion. This will make the hub and the impeller to become displaced relative to the axis of rotation, resulting in extreme fan imbalance. To avoid this condition and ensure proper fan functioning, an interference fit is typically used between hub and shaft connections.

Cracks in shaft or impeller

A shaft or impeller crack is very common in centrifugal fans. The typical reasons for cracking of mechanical parts is the age and fatigue. When crack occurs in shaft or rotor, it can propagate and can cause imbalance in the components causing threat to fan operation. Fan systems that are suspected of having a crack in shaft must be treated in a timely manner before they propagate and become intense.

Rotor mass imbalance

Imbalance in rotor occurs when the center of rotor mass does not coincide with the center of rotation. The uneven distribution of rotor mass or the deterioration of fan rotor due to extreme operating conditions can cause misalignment resulting in fan imbalance and vibration. One way to reduce the level of vibration is by adding a weight to outer diameter of the rotor.

Motor shaft misalignment

Misalignment between a drive motor shaft and a fan shaft typically occurs during new fan installation or when shaftrotor assembly is replaced with a new equipment. When shafts are not straight, it can cause an unbalance and may force the bearings to twist in an oscillatory manner. This can lead to bearing defects, shaft breaking or cracking, coupling failures or excessive vibrations. Shaft misalignment can deteriorate the operating life span of a fan system. Hence it is important to have regular checks on alignment before startup of the fan and subsequently few months after installation.

Critical speed

There exists for any rotating shaft, rotor and bearing combination, a certain speed at which resonant vibration develops. The slightest unbalance will cause the shaft to bend, increasing the unbalance and bending without limit except for damping effects and loss of exact resonance. Thi. Cheap Jerseys Cheap Wholesale Jerseys Cheap Jerseys China Wholesale Cheap NFL Jerseys From China Cheap NFL Jerseys From China Cheap Jerseys China Wholesale Wholesale Jerseys Online Wholesale Jerseys Free Shipping Cheap Replica Soccer Jerseys Cheap Wholesale Jerseys China