Dispensing equipment

Allow for clean application without the need for specialty dispensing equipment or special cure/drying cycles. 

With the exception of fillers, the raw materials used in two-component urethanes are all liquids. The two components have an isocyanate side and a polyol side. The raw materials are combined in various ways in order to produce with liquids that are combined at a 1 1 volume ratio, preferably, thus keeping the dispensing equipment as simple as possible. Fixed ratios of 3 2 or 1 2 are also commonly used. Ratios other than these are possible, but require the use of a... 

Pressure Pressure feed pumping equipment req d mold halves clamped (methods range from clamp frame to pressure pod) None Lows pressure press, capable of 50 psi (hydraulic or pneumatic mechanical) resin dispensing equipment not req d but recommended Hydraulic press, normal range of 100-500 psi (0.69-3.05 MPa) Hydraulic as high as 2,000 psi (138 MPa)... 

D. G. Pope, Specialized Dose Dispensing Equipment, in Formulation of Veterinary Dosage Forms (J. Blodinger, ed.), Marcel Dekker, Inc., New York, 1983, p. 99. 

Liquid ingredient weighing can be an area of considerable problem when accuracy of addition is vital and dispensing equipment, fitted with heaters where required are very necessary to reduce compound variability. 

Rapid cleaning of dispensing equipment when changing the target shade... 

One of the major sources of problems encountered in spin-coating hardware is the dispensing equipment. Frequently it has been recommended that the resist be dispensed directly from the bottle thereby avoiding all mechanical pumps, syringes, or additional filtering equipment. Provided the resist solution has been adequately filtered prior to dispensing, direct application from the bottle should yield the lowest defect films possible. 

CMP slurry is typically shipped to user sites in 20-liter (5-gal) pails for R D evaluation or 200-liter (55-gal) drums or 1000-liter (265-gal) totes for manufacturing. The difference in handling ease of each container varies due to the size, shape, and weight of the container the number, size, and location of openings in the container and the need to insert stirrers, diptubes, or other devices into the container. The variety and nonstandardization of containers present a challenge for slurry distribution equipment manufacturers and additional cost for users every different container potentially requires a different type of connection to the dispense equipment. 

In this section, information on the operational aspects pertaining to the use of admixtures in the field is presented. In addition to details concerned directly with the physical aspects of batching and dispensing equipment and their operation, considerable attention is directed to the material-related problems that arise in the use of admixtures both in mainstream and special applications. It also offers guidance in the selection, use and control of uniformity of the product. Most of the issues discussed here apply equally to the three major fields of concrete construction, namely, site-batched and -placed concrete, ready-mixed concrete, and precast concrete. 

The arrangement of the piping system in the dispensing equipment requires careful attention to ensure that variable amounts of material are not trapped in the lines. 

Simple manual dispensing systems designed for low-volume concrete plants depend solely on the care of the concrete plant operator in batching the proper amount of admixture into a calibration tube and discharging it into the batch. These types of dispensing equipment are used in small-scale operations where admixtures are only occasionally used. For small and occasional additions, hand-dispensing equipment may be used to measure reasonably accurate quantities. A hand-operated plunger can be used to... 

A checklist for monitoring dispensing equipment and procedures should include ... 

Modern systems use BiB packaging for syrups. A double bag is used the inner bag is blended polymers (for example LDPE and EVA) and the outer protective bag is a laminate with an inner layer of metallised polyester sandwiched between LDPE. The bags are sealed with a coupling valve designed to connect only to the drink manufacturer s dispensing equipment and after filling are dropped into cardboard outer boxes. 

More and more pharmacies are using automated dispensing equipment. 

The addition of the correct quantity of each ingredient is important. The dispensing equipment must be suitably sized to cope with the various weight ranges involved. 

The manufacturer s instructions should be carefully followed when using admixtures. Specific effects produced in concrete by admixtures are dependent on the instructions provided by the manufacturer of the admixture and a number of factors such as cement composition, aggregate characteristics, the presence of other admixtures and ambient conditions. The interaction of the selected admixture with these factors and the extent of the side effects should be verified prior to field use. The desired effect should not be too sensitive to small variations in the amount of admixture used, or in the amounts of other concrete constituents used. Since the effects produced may vary with the point of addition in the mixing cycle, a standard mixing sequence should be established and admixtures must not be added during transportation, placing or compaction. Admixtures of all classes may be available in either powder or liquid form and since relatively small quantities are used, it is important that suitable and accurately adjusted dispensing equipment be employed. All liquids, particularly emulsion types, should be protected from exposure to drastic temperatures. 

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