Mixer, heavy-duty

Segments. Segments for heavy-duty use such as for medium-sized tmcks ate produced by a dry-mix process. The fiber, modifiers, and a dry novolak resin are mixed in an appropriate mixer. The blend is then formed into about a 60 by 90 cm preform (or briquet) at 3—4 MPa (400—600 psi). The briquets are hot-pressed for 3—10 min at 140—160°C and then cooled. The resin is only partially cured at this point to be thermoplastic when subsequently reheated for bending. The hot-pressed preforms are then cut to desired size and bent at 170—190°C and cured in curved molds for 4—8 h at 220—280°C. Final grinding produces the finished segments. 

Top entering mixers are heavy duty equipment. They are usually fixed to a rigid structure or tank mounting. Either radial flow or axial flow turbines may be used. Speeds vary from 50 to 100 rpm and usually require a double set of helical gearing or a single set of worm gears to achieve these low speeds. Therefore, they are more expensive than single reduction mixers. 

The second path in Fig. 3 outlines the approach to a more robust tape designed by Drew [21]. Here the milled rubber and filler are combined with tackifiers and other additives/stabilizers in an intensive dispersing step, such as a Mogul or Banbury mixer. Next, a phenolic resin or an alternative crosslinker is added and allowed to react with the rubber crosslinker to a point somewhat short of crosslinking. The compounded mixture is then charged to a heavy duty chum and dissolved in a suitable solvent like mineral spirits. To prepare a masking tape. 

Mixing. Nitrocellulose is introduced into the process as alcohol-wet material in a lumpy condition. Depending on the needs of the subsequent process, it may be subjected to agitation in heavy duty mixers to reduce the size of the lumps. 

Heavy Duty Laboratory Mixer Emulsifier, Model L4RT-A, Silverson Machines Ltd., Waterside Chesham, Bucks., England, HP5 1PQ. 

In the standard wet granulating method used to produce tablet feed in the pharmaceutical industry, sigma blade or heavy duty planetary mixers are often employed [12]. These machines may handle 220 or 440 lb (100 or 200 kg) batches and employ 7 to 10 hp (5.2 to 7.5 kW) drives to knead and... 

New pilot and commercial-scale equipment has been developed to blend and apply the composites and to determine total system costs (Figure 3). Several commercial-sized units based on the pilot design are now under construction. Each has a 500-gal capacity. They are fitted with a hot-oil heating system, heavy-duty mixers, and heated hoses that can deliver up to 200 lb/min of sulfur composite. They are designed to operate typically at 250°-300°F and at spray pressures of 20-100 psi. Each is self-contained except for electrical power which is provided by a stationary source or a portable generator. 

Figure 7.15 (a) Blade for a heavy duty mixer, (b) Troughs of a heavy duty mixer. 

Rubber premixes made using bale rubber are processed in high-intensity Banbury mixers that are widely used in the rubber processing industry. The mixer uses two heavy-duty counterrotating mixer blades to intimately mix fillers and fibers into the rubber. The product of Banbury mixers are either directly formed in a cure press or used as an ingredient in a friction formulation after size reduction. 

The phosphate solution was prepared from reacting analytical grade 85% HjPO and 50% NaOH in a heavy duty mixer. After the temperature of the phosphate solution was cooled to the desired level, the specific amounts of hypochlorite solution at a temperature of 20 C were added. The mixture was mixed for a predetermined time... 

Since the premix is a viscous composition, an intensive heavy duty mixer is required. The vehicle and then the pigment are added to the mixer. Sufficient vehicle to wet the entire pigment load must be used, and there must be enough vehicle so that the paste is fluid enough to charge the mill. The pigments must be thoroughly wet and free from lumps. 

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