Lift trucks, types

The many options available for lift trucks f l into two classes vehicle specialties, which include controls, transmissions, guards, etc. and accessories, which are devices that handle specific types of loads (Fig. 21-55). Included in this second category are high-lift masts, up to 7 m (24 ft) handhng attachments for circular products, such as drums and roll goods attachments such as carton clamps and the fork side-to-side shifting mechanism. 

Materials-handling equipment is logically divided into continuous and batch types, and into classes for the handling of liquids, solids, and gases. Liquids and gases are handled by means of pumps and blowers in pipes, flumes, and ducts and in containers such as drums, cylinders, and tank cars. Solids may be handled by conveyors, bucket elevators, chutes, lift trucks, and pneumatic systems. The selection of materials-handling equipment depends upon the cost and the work to be done. Factors that must be considered in selecting such equipment include ... 

Two different fuel cell power plants have been tested. The alkaline type demonstrated good performance during its trouble-free operation, but due to repeated repair work, it was later stopped. Since 1993, a PAFC power plant of 79 kW(e) is in operation which also allows cogeneration of 180 °C heat. It is fueled with either hydrogen or natural gas to be converted to hydrogen in an upstream steam reformer. A 10 kW PEM fuel cell is operating a standard electric fork lift truck... 

The most versatile power truck is the fork-lift truck which may be powered by an internal combustion engine or batteries. The basic unit is equipped with two forks attached to uprights for lifting standard pallets, but a variety of special-purpose arrangements may be fitted, such as drum grabs and pushing devices. The use of pallets, which are load boards for the assembly of a number of containers to form a unit load , is now almost universal in chemical factories. They are constructed in wood, steel, or light alloy. The most common type is the double-decked pallet which is illustrated in Fig. 2.S. 

Care should be taken to match the size, type and capacity of the truck to the job it is to do. In service, the manufacturer s maintenance schedules should be followed with any necessary repairs being carried out promptly. High-lift trucks should have an overhead guard and those used to load trailers and lorries should have a guard behind the driver (Figure 27.6). 

Robinson Trolley. A circular trolley, weighing 68.1 2.3 kg with three equally-spaced wheels, which can be fitted with various types of rim or tyre. It is rotated over a 4ft x 4ft (1.23 x 1.23 m) test panel of floor tiles to assess resistance to wear or damage by smallwheeled vehicles such as fork-lift trucks, (ASTM C627-76). 

Equipment within the workplace which is used for lifting will vary considerably depending on the type of industry and the load which is to be lifted. For example, in the construction industry, cranes and slings are predominantly used to lift loads. Other industries often use fork-lift trucks to lift and move loads. Lifting devices should be selected to suit the job or task required. For this reason, lifting equipment has limitations on the load weight it may safely lift and the conditions in which it can be used. Enviromnental factors may play an important part in the selection of equipment. 

Many of the hazards and controls required for vehicle movements on construction sites have been covered earlier in this chapter. Common vehicles found on construction sites include site dumper trucks, fork lift trucks with telescopic handlers, all terrain and rough terrain vehicles, excavators and tipper lorries. On larger construction sites various types of earth moving equipment may also be used. 

Applications for materials such as these are in boat hulls, architectural panels and structures, vehicle components, swimming pools and filter parts, athletic equipment, housings for products like computers, office-, business-, medical-, testing-, and display equipment, and storage tanks. Further uses include agricultural fertilizer and feed hoppers, pig and other animal stalls, furniture, bathroom components like shower stalls and modular tub-wall segments, aircraft primary and secondary structures, toys, and many products that must exist in all types of corrosive environments. Pultruded parts include electrical insulators, boom arms for aerial-lift trucks, luggage racks, channels, beams, solid rods, and L beams. 

Shipping and receiving docks are an important factor in warehouse planning because inefficient layouts may use too many lift trucks and personnel to achieve the necessary loading/ unloading rates. Of prime importance is the number of docks and type of equipment needed. Recently, dock management software has been developed to track dock performance and interface with other software. 

Another means of protecting against the explosion hazard in flammable atmospheres is to employ gas detectors. The principle is that the gas detectors detect flammable gas/air mixtures at a low percentage, typically 10%, of the LEL and cause an alarm to sound. If the concentration reaches 25% or so of the LEL, the system automatically initiates a shutdown of the process. This type of technique is commonly used in process plants such as oil and gas refineries, LEG storage tank farms, chlorine doping rooms in water treatment plants, and on vehicles such as electric fork lift trucks operating in Zone 1 and 2 areas. 

A planned maintenance programme should apply to fork-lift trucks. Where trucks will operate in enclosed areas, such as within building structures, or confined spaces, adequate ventilation must be ensured. Public and operatives access to vehicle routes should be limited where practicable. Selection of trucks is required roll-over protection (ROPS) is required where there is a risk of the truck rolling or toppling over. Type of truck should be checked to ensure suitability for the loads to be moved and ground conditions. 

Motive power lead-acid batteries are the power source used in every kind of electric vehicle from road transport to fork lift trucks in industry. Many manufacturers throughout the world supply these types of batteries and it would be impossible to review all their products. Instead, the products of one major UK-based international producer. Chloride Motive Power, are considered in some detail. The applications of these types of batteries are considered in Part 4. 

Figure 9-4. Lift trucks with wing-type seats offer more protection to operators. Always wear your seatbelt.

Industrial trucks can be powered by electric batteries, liquid propane gas (LPG), gasoline, diesel fuel, and compressed natural gas (CNG). Some types of lift trucks should not be used in the presence of certain chemicals or conditions. The current OSHA regulation, 1910.178 for powered industrial trucks, contains descriptions of the various divisions, classes, and groups of classified hazardous areas. The hazardous materials that determine which lift trucks can be used are also listed in the regulation. Since OSHA was promulgated, the number of substances that contribute to fire and/or explosion has greatly increased. 

Each powered industrial truck model and type has its own operating characteristics. When the training of operators is taking place, it is important to discuss the models and types of lift trucks that they will be operating. Controls and safety features may not be the same for each manufacturer s models. Functions, controls, and placement of controls can vary from manufacturer to manufacturer. 

CO emissions taken from a tailpipe of a propane lift truck normally range from 5,000 to 7,500 PPM. When a forklift is operating at full power, these same readings will produce readings of 2,000 to 5,000 PPM. The forklift must be properly maintained and the fuel system must be properly sized and tuned. If the lift truck is poorly maintained, vehicles can yield readings of CO in excess of 10,000 PPM regardless of the type of fuel used. Studies at sites that involved serious CO exposures measured tailpipe emission levels up to 88,000 PPM. Air monitors mounted within the building will help to measure air quality in the warehouse. 

Electric-powered industrial trucks offer a very good solution to the carbon monoxide problem. However, even though electric lift trucks do not produce carbon monoxide, they do present other hazards such as exposure to corrosive battery acid and an explosive atmosphere from the hydrogen gases emitted by the electric truck battery. Each type of powered industrial truck poses its own set of potential problems. 

Despite the type of fuel or power used on lift trucks, safety precautions must be in place. Each source of power has both positive and negative points. Battery-powered vehicles do not produce carbon monoxide but can expose employees to sulfuric acid, the danger of explosion, electricity from chargers, and back injuries from pulling or pushing batteries into place. 

Hydraulic fluids are a very large class of materials that are used in machines and equipment to transfer pressure from one point to another. They are used in many ways including all fluids for car automatic transmissions, brakes, and power steering. Hydraulic fluids are also used in many machines like tractors and other farm equipment, forklift trucks, bulldozers, and other construction equipment, and airplanes. In industry, hydraulic fluids are used in machines that push, lift, pull, turn, and hold things. This profile covers only three of the many types of... 

Compressed Gas Tanks Should be Properly Moved. Compressed gas tanks should never be dragged, slid, or allowed to bang against one another. One should use a proper hand-truck or other suitable device for transporting the specific type of compressed gas tank. Compressed gas tanks should never be lifted by their caps, by magnets, or by ropes, chains, or slings unless the manufacturer has provided attachments (such as lugs) on the tanks. 

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