Factory production quality control

The aggregate material produced for the construction of unbound layers should be periodically tested in order to ensure constant quality and compliance throughout the factory s production period. 

The tests required for determining the aggregates general properties and the minimum required test frequencies can be found in Table C.l of CEN EN 13242 (2007). 

The requirements for graded aggregate material for unbound bases or sub-bases according to American standards are determined by ASTM D 2940 (2009) or AASHTO M 147 (2012). 

Unbound mix Type III (open graded) Type IV (with asphalt arisings)  

Note SDV = suppiier-deciared vaiue grading range (S) Toierance = permitted toierance,from suppiier-deciared vaiue. 

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In the feed and forage industries NIR methods have been used extensively. NIR factory-based quality control schemes have been implemented which enhance the economy with which feed components are used, and the quality and consistency of the final product. Moisture, crude protein, and acid detergent fiber analyses of feeds are being steered through the AO AC (Association of Official Analytical Chemists) validation process. NIR is also used widely in the US tobacco industry for measuring nicotine and other process parameters both on- and offline. 

The first chapter in this section provides a unique account of the ecology, i.e. distribution, survival and life-style, of microorganisms in the factory environment, and should enable process designers, controllers and quality control personnel to comprehend, trace and eradicate the sources of failure due to extraneous microbial contaminants in the finished product. Much of the information given here is applicable to hospital manufacture also, and this is extended in a contribution (Chapter 19) dealing with contamination in hospital pharmaceutical products and in the home. 

Thirty year s ago there would have been a limited set of equipment in the quality control laboratory of the majority of fruit juice and soft dr inks factories. This would probably have consisted of a reffactometer, a burette, a spectrophotometer, an instrument to measure the level of carbonation and some equipment for checking the microbiological integrity of the product. However, with the move to larger... 

Quality control at the factory gate precedes the final release of materials into the production process. Depending on the raw materials and the tests to be carried out, all factories are equipped witii the necessary control systems and facilities. 

In practice in Britain the CMC lead azide is manufactured in a government ordnance factory, so process control is relatively easy. Even though no mention is made of a required output from the azide in the British specification, it is understood that it should perform to a certain standard. In the United States no process is specified for the lead azide, except that it be precipitated in the presence of CMC the batch size is also specified. The process used by independent manufacturers closely resembles the British RD 1333 process [21], and its significance is perhaps best illustrated by the fact that up to 1970 155,000 lb of azide was produced and utilized in the production of nearly one billion detonators and igniters. However, at the time (about 1964) when large quantities of RD 1333 lead azide were being manufactured for the first time in the United States, there remained the question whether small process differences affect the safety and quality of the product. 

The first activated carbon produced in America was developed accidently from an endeavor to find utility for leached black-ash, a waste product in the manufacture of soda pulp.26 When pulverized, black-ash resembles lamp black, and a factory was erected to process it into a pigment. Because of certain cblor characteristics, however, the finished pigment was not generally accepted by the paint and ink industries. Vigorous efforts to find other sales outlets were of no avail and the factory was about to be abandoned, when, quite by accident, one of the workers stumbled on the discovery that black-ash has decolorizing power. The product, now named Filtchar, was sold as a substitute for bone char and fuller s earth. Marketing difficulties soon developed because of uneven quality of the product some batches were satisfactory, others were not. Very few tests were then available to measure decolorizing power and none were suitable for quality control of the Filtchar. 

Every pharmaceutical factory shall have appointed a responsible person with specified responsibilities. This person will have at least fifteen years experience in the scientific and operational areas of drug manufacture. Cooperating with this person shall be a pharmacist in charge of production and another pharmacist in charge of quality control. These personnel (production and quality) shall not report to each other. Each person shall have suitable scientific and technical skills and not less than ten years experience in their areas. 

Often, in the laboratory, one is limited by the amount of material available, and at least there is then the excuse that the tests relate only to the material available at the time. In a factory, where the whole output is available, the problem is a different one. Here the quality control manager has to decide not only what is adequate, but also what is reasonable. bearing in mind the production schedule and the profitability of the operation. 

Quality eontrol embraces the monitoring of incoming materials, the control of the manufacturing processes, and checks of materials and products produced, so as to ensure and maintain the quality of the output from the factory. Physical testing methods are important in this regime, and most of the standardized test methods are intended for quality eontrol use it is probable that the majority of tests carried out are undertaken in the first place for quality assurance purposes. However, this book is about testing and is not a quality eontrol manual, so discussion here is restricted to the quality control of the testing process. 

Mass, dimensions, and density are also important in the factory, being factors in the costing of products and in quality control, from routine checking on dimensional accuracy of components to a simple control measure for the consistency of polymer compounds. 

Small-scale laboratory tests for rubber are used in material and product specifications and for such activities as compound development, component design, factory quality control, and life prediction. Many of these tests have been shaped by the distinguishing features of rubber, rubber products, and their means of manufacture. Such features can conveniently be grouped as follows ... 

Applying procedures and conducting quality control tests at the mixing plant during production will help ensure that the above is achieved. According to the European standard CEN EN 13108-21 (2008), this stage is called Evaluation of Conformity (EC) of all bituminous mixtures produced under specifications. The EC is composed of the Initial Type Testing (ITT) and the Factory Production Control (FPC). 

Inspection can be classified according to who is responsible for the activity there are usually many levels to this chain. Typically, there may be the inspectors of the project management and engineering team, the quality department of the procured item suppliers and contractors (and, separately, their factory production workers, using inspection as a production control tool), and a chain of sub-component and raw material suppliers and their quality departments. 

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