File Name: cause and control of vibration .zip
Wide column spans along with the use of high strength material less of which would provide the needed structural integrity tend to make modern composite floors flexible and oscillatory. Human activities walking, running, dancing, etc.
Order your copy here. Vibration in the workplace affects the body in two distinct ways therefore it is classified as follows:. Regular exposure to hand-arm vibration can cause a range of conditions known as hand-arm vibration syndrome HAVS which includes vibration white finger and carpal tunnel syndrome. Around five million workers are exposed to hand-arm vibration in the workplace. Two million of these workers are exposed to levels of vibration where there are clear risks of developing a condition. Hand-arm vibration arises from the use of hand-held power tools and is the cause of significant ill health ie painful and disabling disorders of the blood vessels, nerves, joints and muscles of the hands and arms.
Easy-to-read, question-and-answer fact sheets covering a wide range of workplace health and safety topics, from hazards to diseases to ergonomics to workplace promotion. Download the free OSH Answers app. Search all fact sheets:. Vibration exposure direction is also important and is measured in defined directions. Vibration frequencies and duration of exposure are also determined. How hard a person grips a tool affects the amount of vibrational energy entering the hands; therefore, hand-grip force is another important factor in the exposure assessment.
Vibration isolation is the process of isolating an object, such as a piece of equipment, from the source of vibrations. Vibration is undesirable in many domains, primarily engineered systems and habitable spaces, and methods have been developed to prevent the transfer of vibration to such systems. Vibrations propagate via mechanical waves and certain mechanical linkages conduct vibrations more efficiently than others. Passive vibration isolation makes use of materials and mechanical linkages that absorb and damp these mechanical waves. Active vibration isolation involves sensors and actuators that produce disruptive interference that cancels-out incoming vibration. Passive vibration isolation is a vast subject, since there are many types of passive vibration isolators used for many different applications. A few of these applications are for industrial equipment such as pumps, motors, HVAC systems, or washing machines; isolation of civil engineering structures from earthquakes base isolation ,  sensitive laboratory equipment, valuable statuary, and high-end audio.
HAV is caused by regular exposure to high levels of vibration from hand held tools and equipment. It could also be caused by holding materials in contact with grinding or cutting operations. The vibration transmitted from the tools or materials to the hands and arms could damage sensory nerves, muscles and joints which is called hand arm vibration syndrome HAVS. This is a condition caused by damage to the circulatory system in the hands and fingers as a result of contact with vibrating tools. The symptoms are.
This article examines the causes of electrical machine vibration, the effects of vibration, and means taken to mitigate vibration. All rotating machines, no matter how well designed and manufactured, exhibit vibration of some form when operating. Excessive vibration can cause damage to the machine or reduce its lifetime, as well as damage to other items. The rotating machines concerned are electric motors and alternator-turbine combinations. Fixed speed machines such as alternators and synchronous motors lend themselves to relatively simple analysis and problem solution.
Easy-to-read, question-and-answer fact sheets covering a wide range of workplace health and safety topics, from hazards to diseases to ergonomics to workplace promotion. Download the free OSH Answers app. Search all fact sheets:. We can feel vibrations and know that people might be exposed to it. But we cannot determine if what we feel is going to be harmful.
Key words: methods of vibration reduction, automatic vibration control. Introduction The reasons of vibrations which disturb normal machines operation.
Beta This is a new way of showing guidance - your feedback will help us improve it. This page tells you how to control these risks and why. More detailed information is available on the main HSE vibration page. The Control of Vibration at Work Regulations says you must prevent or reduce risks from exposure to vibration at work.
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