Wednesday, April 18, 2012

Evrim Berk 030060161 8th Week

1-) Engineering Release Control (organization)

Previous One

There is not any available previous answer

New One - better one

Using the meta-model and its principles of application shown, a process model for the analysis of a release management process at a large manufacturer was created.



The goal of the analysis was to identify improvement measures for the communication among the different organizationtal bodies along the principal process flow for a new product line based on the experience fom the other projects . Specifically, the following aspects were targeted to be improved:
  • Alignment of commities and organizational entities with process chains.
  • Improvement of the assignment of tasks to organizational entitites by reshuffling the work distribituon based o the process sequence, by the targeted deduction of interdependencies between organizational entities, and through the generation of suggestions for an improved organizational step.
(Kreimayer M. Lindemann U., Complexity Metrics in Engineering Design: Managing the Structure of Design Processes, pg: 130)

2-) High Speed Roll Sizing (manufacturing)

Previous One

The use of rolling machines and attachments to roll finish a variety of high volume of automotive,appliance, and electronic parts has proven the speed and reliability of that process. However, it has not been practical to achieve sizing improvements at the same time. The development of ultrastiff die systems and of size control by the feed back of true die position, which can be precisely controlled, opens up new roll sizing opportunities. This new capability, combined with the use of annular preformed surfaces on the parts, now makes it practical to size bearing mounts and other precision diameters to total tolerance ranges of 0.0003 in at production rates of as high as 30 per minute.

(Manufacturing Engineering Handbook, H. Geng, p. 22.60)

New One - better one

Rods or blades meter size onto two soft rolls, one about half the P&J hardness as the other, which form a pressure nip and carry a uniform film of size into the pressure zone for transfer to the sheet. High speed milling (HSM) is used increasingly for machining of sculptured surfaces in which economical cutting speeds of 2,000 m/min are attainable. Even strongly patterned surfaces for inner parts can still be machined with medium feed rates of around 5m/min. Cermets and special PVD-coated carbides are capable of attaining surface qualities of Rt = 10mm, which reduces the need for secondary manual polishing to a minimum.

The size press covers in this type of size press must have excellent abrasion and chemical resistance, and temperature and hardness stability to ensure optimum sizing and long runs between regrinds, while maintaining a suitable surface to uniformly release the sheet and prevent film splitting. The cover needs to hold the appropriate amount of starch/coating and readily transfer it to the sheet.

(Schuler Metal Forming Handbook, 1998, pg:136)

3-) In-Die Staking ( manufacturing)

Previous One - better one

Staking of any hardware is another such operation that could only benefit from automation. Manual staking, similarly to hardware insertion, is cumbersome and slow when done in a separate assembly operation. The inserted hardware is not always large enough for the operator’s fingers to handle, and may often fall down, or be inserted the wrong way, and this way both the sheet-metal part and the hardware may end up in the scrap bin.In-die staking utilizes a standard bowl feeding equipment as well, along with a customized transfer mechanism. The delivery of parts into the die is done via compressed air. A dual escapement bowl feeder can be used when placing two kinds of hardware at a time. The bowl feeder and its PLC controls are positioned on a portable cart, which allows for mobility from press to press. Designed for a quick change, standardized locators are utilized to attach the portable cart to the press, with quick disconnects for stud insertion and PLC controls. To control the process and to monitor the quality of the parts, sensors are being used in the die. The sensors monitor whether or not The material was properly fed The studs are present after staking The alignment of the studs is correct The part is properly ejectedIn this case, proximity sensors are implemented to detect the stud presence; photoelectric through beam sensors are there to verify the stock has fed properly. Another photoelectric sensor oversees the parts’ ejection. And all sensors are integrated with the press controls, to prevent any problems during production.( Ivana Suchy, Handbook of Die Design, McGraw Hill Pub., 2006, Second Edition, p.503-504)

New One

It is a method of fastening two parts termanently. It's a substitute to drilling or punching. In this method, a shaped punch is forced into the top of a projection of one of the parts to be fastened. This indentation action of punch deforms the metal sufficiently to squezze it tightly against the second component so that they are firmly located together.

( Rajput R.K., A t-Textbook of Manufacturing Technology, pg. 207)

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