Fill time quality

Sample balancing problem. Let us consider the multi-cavity injection molding process shown in Fig. 6.54. To achieve equal part quality, the filling time for all cavities must be balanced. For the case in question, we need to balance the cavities by solving for the runner radius R2. For a balanced runner system, the flow rates into all cavities must match. For a given flow rate Q, length L, and radius R, solve for the pressures at the runner system junctures. Assume an isothermal flow of a non-Newtonian shear thinning polymer. Compute the radius R2 for a part molded of polystyrene with a consistency index (m) of 2.8 x 104 Pa-s" and a power law index (n) of 0.28. Use values of L = 10 cm, R = 3 mm, and Q = 20 cm3/s. 

The process parameters that affect the quality of injection molding products include cooling time, injection pressure, injection speed, injection time, filling time, melt temperature, ejecting pressure, mold temperature, mold geometry shape, material property of melt, melt speed, and heat transfer action of flow field. 

The fill time is the time necessary to fill the mold. The fill time is dependent upon the shot size or dosage stroke and the injection rate. Plastic materials have different injection rates associated with them. The pack or hold time is needed to control the part warpage. Likewise, cool time is needed to minimize part warpage due to shrinkage of the plastic material. The time for filling the mold, packing the part, and cooling the part can be optimized to improve the quality of the plastic part and to minimize cycle time. 

Audits of practice against procedure or policy should be recorded as they are observed and you can either do this in note form to be written up later or directly onto observation forms especially designed for the purpose. Some auditors prefer to fill in the forms after the audit and others during the audit. The weakness with the former approach is that there may be some dispute as to the facts if presented some time later. It is therefore safer to get the auditee s endorsement to the facts at the time they are observed. In other types of audits there may not be an auditee present. Audits of procedure against policy can be carried out at a desk. You can check whether the documents of the quality system satisfy all the clauses of the standard at a desk without walking around the site, but you can t check whether the system is documented unless you examine the operations in practice. There may be many activities which make the system work that are not documented. 

The most difficult materials to study by NMR microscopy are those with short T2 or T2 relaxation times and/or with low concentrations of the nudear spins, which normally result in poor NMR signal intensities. One possibility for improving the image quality is to adapt the shape and size of the rf coils to the size of the objects in order to achieve the best possible filling factor and therefore the best sensitivity [1]. In addition, methods with short echo or detection times have been developed, such... 

A variety of detectors is used in the field of X-ray scattering. In fact, the proper choice of the detector (as well as the sample thickness) is essential for good quality of the recorded data, whereas the intensity of the synchrotron radiation determines the minimum cycle time between two snapshots - if a modern CCD detector is used. Gas-filled detectors cannot be used to record high-intensity scattering patterns. Image plates need a minimum time of 2 min for read-out and erasure. 

Electrodeposition of metal onto structured objects, such as circuits, is controlled in part by a template. At the same time, the deposit must fill all the recesses uniformly and seamlessly, the texture and crystal structure must fall within tolerances, and the quality of the features must be sustained over a large workpiece. The distribution of material within recesses or onto widely separated portions of the workpiece is subject to a limited number of macroscopic control-parameters such as applied potential and plating bath composition. Success therefore depends on exploitation of the natural pathways of the process. The spontaneous and unconstrained development of structure must be taken into consideration in the production of highly organized and functional patterns. 

Third, processing times may require special modeling in chemical industry. While in discrete manufacturing processing times for a certain lot are usually dependent on the lot size, i.e., the number of units to be produced, this is often not true in the chemical industry. Here, processing times are often constant, irrespective of whether a reactor is filled to 70% or 90% of its capacity. This is often referred to as batch production [5], On the other hand, the quality of the material produced may depend on resource utilization. Certain reactions may not even be feasible, if a minimum bound of the procured material is not exceeded. This implies additional restrictions regarding the resource utilization level on the planning situation. 

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