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Lot Size

Lot Size refers to the quantity to be ordered or produced. This is an important decision fot any manufacturing facility. Lot sizes generally vary with the type of manufacturing process used. In job shops the lot sizes tend to much smaller; a lot size of  one unit is not uncommon. In line production the lot sizes could be much larger.
     Many mathematical models have been developed to compute optimal or near optimal lot sizes to minimize cost or maximize the revenue or to provide desired level of service. Generally the models take into the account the cost of inventory if what is produced connot be consumed or shipped to consumers immediately. If lot sizes become very small, than the need for frequent setup of production facilities or the need for placing several orders with suppliers increase. This may lead into increased setup or order cost. Mathematical models balance these and and other costs to compute an optimal model.
      Under just in time production or lean production lot sizes tend to be small and not exceed the immediate demand. This philosophy prevents inverntory buildup and costs associated with inventory holding and inventory management.
Paul M. Swamidass, Encylopedia of Production and Manufacturing Management, P. 381-382

High Cycle Fatigue

High numbers of cycles to produce fatigue failure, It is called High Cycle Fatigue.  High Cycle Fatigue occurs when the numbers of cycles are greater than about 10^4 or 10^5 cycles.
Jack A. Collins, Failure Of Materials In Mechanical Desing : Analysis, Prediction, Prevnetion P.179

Computer aided production management

Computer aided production management  is the use of computers to improve the efficiency and the effectiveness of the production management. It is concerned with what to manufacture, in which order and by when.
   CAPM as being:
concerned with the executing of costumers' orders, efficiently, economically. Its concerned with.
1. Knowing at all times what delivery dates can be offered realistically, taking account of existing commitments.
2. Planing future capacity to meet sales opportunities
3. Ensuring te right materials are ordered.
4. ensuring that work in progress proceeds through the manufacturing stages in the righ sequence.
5. providing the flexibility to meet changing costumer requirements or priorities without incuring excess inventory.
Stephen J. Childe, An Introduction to computer aided production management. P.34


Durometer Hardness Test
This test method is based on the speciment indentor , forced into the material under specified conditions. The indentation of hardness is inversly related to penetration and is dependent on elastic modulus and visco elastic behavior of material.

 A. B. Mathur,I. S. Bhardwaj, Testing and Evalutation of Plastics, P.160


to be continued...