Plate compactors

Vibrating-plate compactor Mass per square metre of base plate > 1400 kg up to 1800 kg 8 Unsuitable Unsuitable... 

The replaced unbound material should be laid in layers of not more than 100 to 150 mm, for the unbound material, or 50 to 100 mm, for asphalt. Compaction should also be sufficient using a vibratory plate compactor, for small patches, or a vibratory/static roller, for larger areas. 

Pneumatic-tyred roller below 1500 kg per wheel Vibrating roller Vibrating plate compactor Vibro-tamper Sheepsfoot roller Smooth-wheeled roller Pneumatic-tyred roller Vibratory roller over 70 kg per 100 mm roll Vibratory plate compactor over 1400 kg rrr of baseplate Vibro-tamper Power rammer... 

Describe the hazards associated with the use of a pedestrian-operated plate compactor being used on a highway. 

Various types of equipment are available single-drum vibratory rollers, towed single-drum vibratory rollers, vibratory tandem rollers, hand-held tampers and vibratory plate compactors. Most of the vibratory rollers have a smooth drum and are suitable for granular material only. Vibratory rollers have weights that typically range between 4 and 25 tonnes and generally move at speeds not exceeding 6 km/hr. 

Vertical-plate extractor. Exemplified by the Bonotto extractor (Fig. 18-79), this consists of a column divided into cylindrical compartments by equispaced horizontal plates. Each plate has a radial opening staggered 180° from the openings of the plates immediately above and below it, and each is wiped by a rotating radial blade. Alternatively, the plates may be mounted on a coaxial shaft and rotated past stationary blades. The solids, fed to the top plate, thus are caused to fall to each lower plate in succession. The solids fall as a curtain into solvent which flows upward through the tower. They are discharged by a screw conveyor and compactor. Like the Bollman extractor, the Bonotto has been virtually displaced by horizontal belt or tray percolators for the extraction of oil seeds. 

In many instances the flow coat or electrocoat primer serves as the finish coat as in dryer drums and bulkheads, air conditioner cabinets and trash compactor boxes, back plates, and other small parts. 

Elimination of screen (10) Since fines separated at this point amount to only 10% (mostly leakage from the compactor cheek plates) screen (10) may be eliminated. However, crusher screen (13) and/or primary granulator (22), if applicable, may be less efficient. 

A novel stainless steel encasing that leads to the compactor rolls encloses the variable-speed auger screws. Just before the nip area, a pair of sintered stainless steel segments are assembled within the horizontal auger feed system, which can operate under partial vacuum. A small, self-contained vacuum pump draws negative pressure through a dry filter and a stainless steel line connected to the sintered assembly plates. The partial vacuum is adjustable from —0.1 to 0.8 bars. The compaction rolls... 

Figure 17 Compactor side view of auger feed screw system and sintered plate segment. (From Ref. 13.)...

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