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Marking out equipment

In order to establish a datum from which all measurements are made a reference surface is required. This reference surface takes the form of a large flat surface called a surface table (Fig. 3.6) upon which the measuring equipment is used. [Pg.48]

Surface plates (Fig. 3.7) are smaller reference surfaces and are placed on a bench for use with smaller workpieces. For general use, both surface tables and surface plates are made from cast iron machined to various grades of accuracy. For high-accuracy inspection work and for use in standards rooms, surface tables and plates made from granite are available. [Pg.48]

The workpiece can be set on parallels to raise it off the reference surface and still maintain paraUelism. Parallels are made in pairs to precisely the same dimensions, from hardened steel, finish ground, with their opposite faces parallel and adjacent faces square. A variety of sizes should be available for use when marking out. [Pg.48]

When the workpiece has to be positioned at 90° to the reference surface, it can be clamped to an angle plate (Fig. 3.10). Angle plates are usually made from cast iron and the edges and faces are accurately machined flat, square and parallel. Slots are provided in the faces for easy clamping of the workpiece. Angle plates may be plain or adjustable. [Pg.49]

The combination set consists of a graduated hardened steel rule on which any of three separate heads - protractor, square or centre head -can be mounted. The rule has a slot in which each head slides and can be locked at any position along its length. [Pg.50]


The main use of surface plates and tables is as a reference or datum surface upon which inspection and marking-out equipment are used. [Pg.82]

The driver equipment compliance check should be used to record results of motor vehicle inspections conducted by authorized FHWA personnel. Motor vehicles declared out-of-service should not be used until fixed. Authorized personnel will declare and mark out-of-service on any motor vehicle that by reason of its mechanical condition or loading would likely cause an accident or a breakdown. An out-of-service vehicle sticker should be used to mark such vehicles. No motor vehicle carrier will require or permit any person to operate, nor will any person operate any motor vehicle declared and marked out-of-service, until all required repairs have been satisfactorily completed. The term operate as used in this section should include towing the vehicle however, vehicles marked out-of-service may be towed away by means of a crane or hoist. A vehicle combination consisting of an emergency towing vehicle and an out-of-service vehicle should not be operated unless such a combination meets the performance requirements of the driver equipment compliance check. [Pg.82]

Where conformity assessment involves intervention of third party, that task is normally carried out by the notified body. The pressure equipment directive enables in addition the national authorities to authorise in their territory user inspectorates for the carrying out of conformity assessment procedures which relate to product verification. These inspectorates shall act exclusively on behalf of the group of which they are part. The placing on the market and putting into service of equipment which has undergone such assessment is however limited to the territory of the authorising Member State and to those Member States which have also proceeded to such authorisation. The equipment concerned shall therefore not bear the CE-marking. [Pg.943]

Another example is the purification of a P-lactam antibiotic, where process-scale reversed-phase separations began to be used around 1983 when suitable, high pressure process-scale equipment became available. A reversed-phase microparticulate (55—105 p.m particle size) C g siUca column, with a mobile phase of aqueous methanol having 0.1 Af ammonium phosphate at pH 5.3, was able to fractionate out impurities not readily removed by hquid—hquid extraction (37). Optimization of the separation resulted in recovery of product at 93% purity and 95% yield. This type of separation differs markedly from protein purification in feed concentration ( i 50 200 g/L for cefonicid vs 1 to 10 g/L for protein), molecular weight of impurities (<5000 compared to 10,000—100,000 for proteins), and throughputs ( i l-2 mg/(g stationary phasemin) compared to 0.01—0.1 mg/(gmin) for proteins). [Pg.55]

Determining the number of theoretical and actual trays in a distillation column is only part of the design necessary to ensure system performance. The interpretation of distillation, absorption, or stripping requirements into a mechanical vessel with internal components (trays or packing, see Chapter 9) to carry out the function requires use of theoretical and empirical data. The costs of this equipment are markedly influenced by the column diameter and the intricacies of the trays, such as caps, risers, weirs, downcomers, perforations, etc. Calcvdated tray efficiencies for determination of actual trays can be lost by any unbalanced and improperly designed tray. [Pg.122]

In the electronics industry, a large number of relatively small firms play a key role in generating new process concepts and equipment. These firms face important research problems in fundamental science and engineering that would benefit markedly from the insights of academic chemical engineering researchers. Academic researchers should seek out and forge links to these small firms that stand at the crucial step between laboratory research and production processes. Potential mechanisms for accomplishing this are described in Chapter 10. [Pg.72]

Safety signs of approved types, available from laboratory supply houses and safety equipment dealers, should be posted in appropriate spots. The door leading out of the laboratory should be marked EXIT, while the door to a back room should be marked NO EXIT. The location of a fire extinguisher must be clearly marked. Signs are available for every type of hazard. Homemade signs not conforming to official standards should not be considered. [Pg.54]

Experiments to examine rhizodeposition can vary markedly in scale and complexity depending on the information required, the equipment available, and the plants concerned. In general, experiments to study exudates and other material lost from young roots are the simplest and are carried out in the laboratory under controlled conditions. Plants are grown in nutrient solution culture, sometimes with sand or other solid support systems, and compounds released into the culture solution are collected and analyzed chemically. The experiments are mainly short-term and the roots can be kept sterile if required. Techniques are also available to label plants growing in these systems with C and to monitor the presence of the isotopes in the rhizodeposits. [Pg.374]

No equipment lasts forever. Therefore, if it is defective or its operation is out of the specified limits, it has to be marked as out of service . There must be regulations in the quality manual on how this should be done, what must be arranged, who has to be informed and who is responsible for looking for a replacement. [Pg.152]

Cotton or wood cellulose is introduced into an iron box 1 equipped with a metal mesh bottom occupying the outside position. By means of a chain and sprocket mechanism the box is moved in position 2 and later to the position 3. Meanwhile another box 1 is loaded and so on. Finally the box from position 3 is transferred to the neighbouring chamber, position 4, to be shifted gradually downwards to the positions 5 and 6, and thereafter to the position 1 and outside again. There the dried cotton is unloaded and replaced by a fresh batch. Drying cellulose in chamber (I) is co-current process, while in the chamber (II) a counter-current process is carried out. The movement of shelves carrying the cellulose is marked as a thick line, while a thin line indicates the direction of air. [Pg.370]

Analytical laboratories have absorbed developments in the automation of laboratory equipment that has markedly influenced the way that they are managed for over thirty years. In the last ten years, automation has spread to the synthetic laboratories of chemical companies and is also making a big impact on the way both product research and process development are carried out. These developments have consequences for R D Managers, which are discussed in this Section. [Pg.66]

Manipulator. To test the residual moisture in a product in addition to the measurement of desorption rate, the freeze dryer could be equipped with a manipulator (Figure 31) and a vacuum lock, which permits one to take out the sample or to close marked vials with a stopper inside the chamber. [Pg.115]

Marks should be awarded for tidiness, economy in the use of glass tubing, and efficiency in setting out the equipment before the, practical work begins and clearing everything away when it is finished. [Pg.111]

The influence of the sulfite concentration on ip is seen in Fig. 10b. As previously shown, the specific absorption rate decreases as the Na2S03 concentration increases (curve a). However, experiments carried out keeping the initial sulfite plus sulfate concentration constant by the addition of Na2S04 show a less marked decrease (curve b). More careful analysis reveals that the specific rate of absorption is independent of sulfite concentration when the experiments are carried out keeping a constant total sulfite plus sulfate concentration. This is demonstrated by recycling a solution partially oxidized into sulfate through the equipment (curve c). This interpretation may explain the different values of n published in the literature. [Pg.60]


See other pages where Marking out equipment is mentioned: [Pg.48]    [Pg.46]    [Pg.336]    [Pg.48]    [Pg.46]    [Pg.336]    [Pg.47]    [Pg.296]    [Pg.306]    [Pg.72]    [Pg.35]    [Pg.143]    [Pg.364]    [Pg.91]    [Pg.575]    [Pg.194]    [Pg.112]    [Pg.164]    [Pg.65]    [Pg.167]    [Pg.125]    [Pg.60]    [Pg.564]    [Pg.3]    [Pg.80]    [Pg.437]    [Pg.986]    [Pg.143]    [Pg.135]    [Pg.100]    [Pg.80]    [Pg.280]    [Pg.229]    [Pg.1009]    [Pg.154]   


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Marking out

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