Lifts and hoists

Generally same as the crane motors, but eompartitively silent in running and have a very low vibration level. For general requirements of other types of lifting and hoisting applications see Table 7.1. 

Maintenance of work equipment in good repair - from simple checks on hand tools such as loose hammer heads to specific checks on lifts and hoists. When maintenance work is carried out it should be done in safety and without risk to health. 

The other types of lifting equipment to be considered are cranes (mobile overhead and jib), lifts and hoists and lifting tackle. A sample risk assessment for the use of lifting equipment is given in Appendix 13.3. 

The equipment should be inspected at suitable intervals between thorough examinations. The frequency and the extent of the inspection is determined by the level of risk presented by the lifting equipment. A report or record should be made of the inspection which should be kept until the next inspection. Unless stated otherwise, lifts and hoists should be inspected every week. 

Summarise project requirements for operators of lifting and hoisting equipment to hold training and competence certificates ... 

Skip Hoists These hoists, which operate on a batch rather than continuous principle, are not so widely used as in the past. However, for high lifts and extremely lumpy or hot materials, the skip hoist is still an economical and practical device. 

With the application of solid-state technology, however, as di.scussed above, the potential energy of the loads in hoists, lifts and conveyors during descents can be saved and fed back to the source. 

This means repeated short-duration application of power to the motor to cause small movements of the shaft from rest to perform certain load requirements. The motor may normally not reach its full speed, nor at times complete even one full revolution, and can be rotated in either direction. Likely applications may relate to lifting or hoisting which may call for delicate handling and a rather slow, smooth and more accurate final movement for exact positioning, lifting or unloading etc. 

Define the process time of each operation and set the hoist to dip. lift and carry the job to the next tank etc. 

Inspection by independent persons or bodies for safety purposes goes back to the middle of the nineteenth century. At that time, the focus of concern was the explosion of steam boilers, and this hazard was most prevalent in the textile industry. Consequently, a group of public-spirited individuals formed the Manchester Steam Users Association for the Prevention of Boiler Explosion. This body carried out boiler examinations and later added insurance as an inducement to the plant owners. By the beginning of the twentieth century steam and gas engines and electrical machines had been added, followed by lifts, cranes and hoisting machines. 

Fig. 2.56. Freeze drying plant, type CONRAD 800, as shown in Fig. 2.54. In this plant, two trays are pushed in parallel through the tunnel. The two heating systems can be seen, and in front of these are the two lifts, which hoist the tray to required level. The two locks for the trays are on the left and right side, in the lower part of the tunnel. This plant produces approx. 3000 tonnes of freeze dried coffee granulate per year (photograph Atlas Industries A/S, DK-2750 Ballerup).

Chicago boom Boom mounted to existing structure which acts as mast, and to which is attached boom topping lift and pivoting boom support bracket. Load lines operated from independent hoist. Swing angle from 180 to 270deg (3.14 to 4.71 rad). function of support structure... 

In friction lifting mine, Hoisting System run by the friction between the head rope and the friction wheel, the safety and reliability of the first line directly affect safety. According to coal mine safety rules , the head rope needs to be replaced every 2 years, if broken wire, corrosion, wear is overrun, rope diameter shrinkage exceed limit, and so on appeared on the head rope, it must be replaced in time, even if less than two years. 

Do not violate any statutory regulations—lifting devices, chain pulley blocks, and hoisting cranes shall be regularly tested as per instructions. 

The lift and load capacity of hoist and belt conveyor systems depend on the strength and weight properties of the hoist ropes and conveyor belts. This paper presents an analysis of the cmrent limits of appHcation of steel wire ropes and steel cord conveyor belts for haulage in imderground mass mining operations. These limits of application are illustrated with reference to a beyond super haulcige system duty of 2000 m 60 Mt/a, i.e., 10000 t/h 6000 h/a. 

The lift and load capacity of hoist and belt conveyor systems depend on the strength and weight properties of hoist ropes and conveyor belts. 

HOISTS AND BELT CONVEYORS—LIMITS OF LIFT AND PRODUCTION... 

As project experience has been gained with the super-deep single lift shafts, a munber of realities have emerged. The hoisting plants associated with these single-lift and deep shafts are very expensive to construct, install and maintain. This is especially true of very specialized systems such as the Blair hoisting systems, when employed to depths exceeding 2500 meters. 

Failure Effect 4. Sudden disengagement of the main hoist gear reduction assembly would result in the loss of the torque used for lifting and/or holding the load. The result would be a loss of the load (the suspended boat could drop). Possible personnel injury or death and severe equipment or property damage or loss. 

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