Assembly problems

Make shaft stiffen by supporting it with intermediate plates welded to both shaft and shell. Alignment and assembly problems and higher cost. 

When toleranees are mentioned in terms of meehanieal assemblies, one eonsiders toleranee or assembly staek models used to determine the final assembly toleranee eapability for a given set of eomponent toleranees. Worst ease or statistieal equations are eommonly used for optimization purposes, as diseussed in detail in Chapter 3. However, this ean be eonfusing, as a toleranee ean exist on a eomponent eharaeteristie, but the eomponent itself may not neeessarily be eapable of being assembled to form the assembly toleranee. This may be due to one or more features of the eomponents being assembled preventing effeetive and repeatable plaeement. If this oeeurs then the produet suffers not only from an assembly problem, but also a toleranee problem. 

I also wish to express my appreciation to David Strasfeld, Gil Nathanson, John Harriman, and (particularly) Bob Bird, who suggested helpful improvements to an early draft to Mark Wendt, who prepared the rendered graphics for the cover and Figure 11.1 and to John Herbert, Phillip Thomas, and David Strasfeld (all former teaching assistants in Chem 561), who assembled problems and exercises to accompany the book. 

The alignment of discrete detectors for each input is no less a difficult task than the source assembly problem. The extra traces associated with connecting discrete field effect transistors (FETs), PIN diodes, or avalanche photodiodes leads to degradation of signal, lower reliability, and greater cost. The integration of photo FETs onto the IC does provide a way to simplify the detector side of the problem, unfortunately at the... 

The blockage of spray nozzles causes many problems, especially for slurry feed. Usually, the earlier the problem is identified, the easier it is to unplug the nozzle. It is always a good idea to use simple nozzles to eliminate assembly problems. Nozzles that can be cleaned in-situ or easily removed are preferable. 

Any assembly problems should be resolved before the system is released for Development Testing. If necessary, assembly procedures should be revised with any necessary corrections. Packaged computer systems do not need to be disassembled during Development Testing or User Qualification so long as assembled hardware units are sealed. 

There is merit in the view that forces and entropy are important. There is merit in the view that geometry is a determining factor in self-assembly. But there have been few attempts at model self-assembly problems which embrace both views. The aim of this paper is to develop a simple theory dealing with one area of self-assembly, the spontaneous aggregation of one-component lipid suspensions, where the fusion of both notions results in a unification of a multiplicity of diverse observations. 

Error Laser scanning assembly problem. Test and replace, if necessary. Printer will not print as long as this error exists. 

Before you unclamp the pieces, mark each piece so that you will know exactly which piece goes where, when you are ready for final assembly. This is very important, as minor variations can cause assembly problems if the holes don t match exactly. 

The global sequence assembly problem can be divided into three steps ... 

Ensure manufacturability at reasonable cost. Check for tooling adequacy and assembly problems. 

Two approaches to the problem were considered an integral lining and a bladder-type lining. Each has its advantages, but reduced assembly problems and prospectively more reliable fitting and attachment installation pointed to the integrally lined tank as the more feasible approach. 

As part dimensions decrease, it becomes increasingly difficult to handle them by traditional methods. Instead, at the microscale, many systems are made with little or no assembly of submillimeter components. To do this, each process and material used in manufacturing the system must be compatible with all the previous processes. When it works, this approach avoids the assembly problem, but it comes with penalties in cost and performance. 

The number, duration and complexity of the tasks necessary to fully rebuild a used hoist are frequently underestimated. Table 1 provides a listing of some of the refurbishment tasks and their relative costs as a percent of the total hoist cost. Figure 1 shows a modern production facility for new hoists, where parts tracking and assembly are tightly controlled. Figure 2 show parts as received for an overhaul project. The part identification was not ideal and led to assembly problems and cost overruns. The most cost effective time to repair a hoist is during the refurbishment phase so it is critical to ensure that necessary rework is identified and completed prior to rebuilding the hoist Once the hoist has been rebuilt and installed, repairs become extremely expensive. 

Nagarajan, M. and Bassok, Y. (2002). A bargaining framework in supply chains-the assembly problem. Technical report, Marshall School of Business, University of Southern California, Los Angeles, CA. 

Component heating or the use of slow-curing adhesives will solve most of the assembly problems of very large interference fitted parts. Another satisfactory approach is to use tapered components. 

Thickness. When PCBs had all through hole components, solder mask thickness was not of much concern. However, with the advent of surface-mount technology in the 1980s, excessive solder mask thickness caused assembly problems, including ... 

In general, assembly problems are caused by a number of factors ... 

Under these conditions, a chemist s approach to polymers allows a specific solution to be offered to virtually any assembly problem. Whether this solution will be applicable or not depends afterwards on the correlations between structural and morphological characteristics of the raw polymer materials, physical properties, the mechanics or thermo-mechanics of the formulations, and the characteristics of the joint (via the characteristics of the assemblies). In this regard, we know that ... 

The design condition requires that the joint is totally filled with the adhesive and that none is extruded from the joint which may contaminate the surfaces of the assembly, produce an unacceptable visual condition, form a water or mud trap or contaminate the production tooling, resulting in costly cleaning operations and the risk of contaminating subsequent assemblies. Problems of this type cannot be tolerated in a mass production environment. 

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