ASSIGNMENT 2

ASSIGNMENT 2

Question 1.6

The support of thin steel strip on a cushion of air introduces exciting prospects for the processing and handling of coated steel strip. Develop a feasibility analysis for the concept.

1. Problem Statement

The finishing line surface of coated steel strip can experience surface defects and unstable running due to the vibration that exists during the process.To prevent the the effects from the vibration ,we need to make sure that the strip run steadily without vibration and without support by the rolls

2. Objectives

• To reduce the vibration on the strip.
• Get proper theory on the effect of the air cushion method on the prevention of the strip vibration
• To study the the processing and handling of coated steel strip.
• To find solution to make sure a stable running of a steel strip.

3. Explanation of existing solution

To lessen the vibration, engineers depend on air cushions. Designs for the most part utilize air cushion for end-of-stroke damping in these cases. There are two sorts of air cushioning, which are traditional and computerized. Air cushion are variable-opening air dashpots. As the barrel cycles, a spud on either side of the cylinder shuts an entry to the fundamental cylinder chamber. This traps air in the chamber end top and drains it off through a little port controlled by a needle valve. The barrel traps an altered volume of air every cycle. But since air is compressible, the weight, heap, and speed in the chamber all influence air-cushion execution.

4. Explanation Theory

In conventional air cushioning, these are not attach and-play equipment. Professionals maintenance specialists must conform the air-pad valves, and that relies on upon the barrel's working weight, speed, and load. The cushion will be needed to be reset if any of these parameters are changed or else it can decrease the productivity of the machine and experience failure due to overload impact.
Another kind of air cushion naturally adjusts to developing conditions, dispensing with the problems on manual modification. It can expand efficiency and lessen the costs. Self adjusting cushion has developed in purpose to eliminate the manual modification. The fact is, the only difference is that they work the same way as the air cushion, but the padding air depletes through indents in the padding cylinder, not past a movable needle valve.

5. Advantages

Self-adjusting end-position cushions offer several advantages over other designs. Manually adjusting the end-position damping of linear actuators is time consuming and can only be done effectively once the actuator is installed and operating under load. By then, the automation-equipment supplier is invariably under pressure to complete the task as quickly as possible.Adjustment also frequently involves two people — one to operate the appropriate pneumatic valve, the other to set the actuator’s damping characteristics. As with all moving parts, access can be potentially hazardous, so safety considerations dictate that only experienced personnel should perform these operations.And the reality is, different people set the valves differently. That often means actuators are less-than-perfectly adjusted. Underdamping results in higher end-position impacts, more noise, and increased wear; overdamping results in longer machine cycle times.

6. Disadvantages

Cannot be used when the cylinder is operated at its limits
(heavy loads, very high or low speeds).

7. Any other of possible solution

Another way to reduce vibration is by using the magnetic damping. Magnetic damping is a form of damping occurs when a magnetic field move across a conductor. The flow of the electrons in the conductor creates an opposing magnetic field and the movement of magnetic field induce an eddy current which result in damping of the magnet. Strong magnet can be produced if we use such a rare earth metal like neodymium as the source of magnet and we can clearly observe the magnetic damping phenomenon.