Fabric scheduling

Review shop fabrication schedules and observe progress of work in the shops and receipt of outside purchased equipment. Evaluate and determine if the shop scheduled versus actual work performance by the manufacturer is meeting the overall schedule. 

In recent years a great amount of work has been done on wafer fabrication scheduling (see Hadavi and Voigt 1987). The reason for this activity is that equipment as well as products are extremely expensive. There is a great deal of randomness in the process machines break down often and processing times are random. The machine environment can be considered as a job shop or as a flowshop with recirculation. 

Additional operator training has been rescheduled from April to mid-May or June because of fabrication schedules at Scientific Measurements. 

The economic studies first performed in connection with this work indicated significant advantages for large quantity fabricating schedules. Recognizing a need for this type of equipment, it was decided to consider fabrication schedules to give production quantities sufficient to meet large requirements of many potential users. 

The results of the morphological study were used to outline an improved fabrication schedule for Zircaloy-2 [132]. This schedule has been used successfully by commercial fabricators while more complete fabrication studies are being made. The material obtained from this procedure has a microstructure such as that shown in Fig. 5-21. It is essentially free of stringers, contains little or no intcrmetallic precipitate, and has small equiaxed grains with essentially a random orientation as seen under polarized light. 

Air cleaning (dust collection) can be cost effective for LVHV systems handling valuable dusts. Care must be taken when handling potentially toxic dusts from air cleaners. Regular, routine reconditioning of fabric filters (e.g., by automatic shaking or pneumatic pulsing) is impottant. This can be accomplished on a set maintenance schedule or as a function of pressure drop across the fabric filter. It is not recommended to recirculate airflow back to the workplace because of the low air volume and potential hazards in the event of filter failures. 

Physical realizability is often the most difficult of the above three corollary questions to answer. In general, to answer this question it is necessary to know 1) whether the materials and components required by the engineering design are available and 2) whether the manufacturing (and/or fabrication) techniques and skilled craftsmen needed to fabricate the product are also available. These two assessments are difficult to make because they often involve the projection of future technological developments. Technological developments usually do not occur according to schedule. 

Material and service schedules for important items of material or installed equipment indicating deadlines for such steps as preparation of shop drawings or samples, beginning of fabrication, date of shipment and date needed at the job site. 

On August 14, 2002, a 1-in chlorine transfer hose (CTH) used in a rail-car offloading operation at DPC Enterprises in Festus, Missouri, catastrophically ruptured and initiated a sequence of events that led to the release of 48,000 lb of chlorine into neighboring areas. The material of construction of the ruptured hose was incorrect. The distributor fabricated bulk CTH with Schedule 80 Monel 400 end fittings and a high-density polyethylene spiral guard. Three hoses were shipped directly to the Festus facility from the distributor two were put into service on June 15, 2002. The hose involved in the incident failed after 59 days in service. 

Blast resistant doors arc not "off the shelf items, They are built to order and manufacturers generally require 6 to 8 weeks after notification of approval of the shop drawings and design data to schedule and fabricate low-range doors, 10-12 weeks for mid-range doors, and 12 weeks or more for high-range doors. 

Involves a detail review of planning, design, procurement, fabrication, and installation functions to achieve the best overall project safety performance, lowest CAPEX, and the shortest reasonable schedule... 

Recommendation 3-la. The Army should develop criteria and a schedule for resolving design and operational issues raised in the 1998 report, Using Supercritical Water Oxidation to Treat Hydrolysate from VX Neutralization, that have not yet been resolved for supercritical water oxidation operation at Newport. These issues include materials of construction, fabrication methods, system plugging, pressure let-down, and the duration of successful continuous pilot-scale operations. 

Another factor to be considered is the time required to fabricate additional liners if the initial supply is depleted. Recently, General Atomics claimed it was able to fabricate 20-mil thick liners of the required diameter for the reactor. General Atomics plans to float a precious-metal liner in a cylindrical Hastelloy pressure vessel and use cooled elastomeric O-rings that have performed satisfactorily on other SCWO systems to form the SCWO reactor. The annular space between the liner and the vessel wall will be monitored for leaks to indicate when change-out of the liner is required. No decision has been made yet on whether to use platinum or Pt-20%Ir. Because they have markedly different mechanical properties, these two liner materials may require significantly different fabrication methods. Platinum is relatively weak and very ductile Pt-20%Ir is less ductile but 10 times stronger. Final selection of the liner material for use at the NECDF was scheduled for early 2000. Fabrication... 

The required heat-transfer area of 19.5 m2 is based on an overall heat-transfer coefficient of 102 W/(m2 K). The best exchanger geometry for this application includes six internal baffles, one shell-side pass and two tube-side passes. The shell is fabricated from standard carbon steel piping of nominal pipe size 30, schedule number 80. The 112 tubes required are each 1.83 m long and 38.1 mm (1.5 in.) o.d. (BWG 12). The tubes must be fabricated from stainless steel type 250 for reasons of temperature tolerance. 

The shell is constructed from carbon steel and will be fabricated from standard pipe of nominal size 30, schedule number 80. The 112 tubes required are 1.83 m (6ft) lengths and standard BWG 12. The tubes are made from stainless steel type 250 as recommended in the Australian Design Code AS1548 Design of Boilers and Pressure Vessels. 

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