When designing intrashop and interdepartmental transport, it is necessary, in all possible cases, to provide for a single transport process with the movement of processed materials and products from warehouses to processing sites by one mode of transport. At the same time, overloading from the inter-shop transport to the intra-shop transport is excluded. The type of intrashop and interdepartmental transport of the enterprise is selected on the basis of technical and economic comparisons of options, taking into account the use of vehicles and equipment that are optimal for a given production.
At the same time, it is recommended to give preference to automobile and battery loaders, electric and autocars, tractors, motorized carriages, automobile, pneumatic, hydraulic transport, belt conveyors, overhead ropes and single-rail roads, hermetic augers and elevators.
For loads up to 5 tons inclusive, it is recommended to use overhead lifting and transport equipment in the form of conveyors, monorails, cranes, and, where appropriate, pneumatic and hydraulic transport.
Intrashop transport is designed to move goods inside industrial buildings - from warehouses to equipment, between departments of a shop, unit groups, from car to car.
Intrashop transport is subdivided into separate types:
- by the nature of the transported goods (bulk or piece);
- by the method of movement (pneumatic and mechanical);
- in the direction of movement (vertical and horizontal).
By the time of action, the transport is divided into two main groups: periodic and continuous action.
Intermittent transport
Floor transport. It moves directly on the floor, delivers goods to any point in the workshop. Does not affect the building construction, with the exception of the floor structure. Leads to loss of production space. Divided into rail, trackless and trailed. This is the most flexible form of transport.
Rail transport moves on a track, the construction of which requires significant construction work. This includes gantry (portal) cranes, trolleys, platforms, the control of which can be manual or motorized.
Roadless transport - lift trucks, carts, platforms - manual or motorized, equipped with devices for loading and unloading, or without them. Carrying capacity - up to 700 kg, speed - up to 10 km / h.
Trailed transport consists of a tractor unit with trailed bogies or platforms forming a train. Tractors can be with auto or electric motors.
Overhead cranes move loads of different weight and shape in three mutually perpendicular directions. They consist of a bridge formed by beams or trusses, the support ends of which are equipped with rollers or wheels for movement along crane runways. A trolley with a mechanism for moving loads moves along the upper belt of the bridge. Lifting mechanisms are equipped with hooks or other devices that ensure the capture of the load.
Bridge cranes with a lifting capacity of 15 to 350 t are equipped with two hooks and two winches, one of which has a large lifting capacity (main hoist mechanism), the other - a smaller one for lifting light loads (auxiliary hoist mechanism). Power supply of cranes with current is carried out using trolley wires suspended from crane beams or the lower belt of the roof trusses. In the latter case, a free space of at least 400 m is provided above the crane trolley. In other cases, the distance from the crane to the supporting structures of the frame must be at least 100 mm. These cranes are classified into heavy duty, medium duty and light duty.
In buildings equipped with cranes, the height from the floor to the top of the crane runway is taken depending on the size of the equipment, the dimensions of the transported goods, the method of transportation, the nature of production, the presence of a railway input and safety measures.
With a small weight of the loads being lifted, single-girder cranes should be used, consisting of a steel I-beam equipped at the ends with rollers moving along the lower flanges of I-beams suspended from the roof trusses (overhead transport). Crane rollers are arranged on a long base to avoid distortions when moving along the span. An electric winch (telpher) moves along the bottom shelf of the crane beam, controlled by switches suspended from it.
Suspended monorail tracks are a reel electric winch moving along the lower flange of a monorail attached to the supporting structures of the pavement. It serves only a narrow strip of the working space located under it, which is a disadvantage and limits its scope. Carrying capacity - 1; 2; 3; 5 and 10 t.
Continuous transport
Belt conveyors (conveyors) are used for intrashop movement of piece or bulk cargo in horizontal and inclined directions. Conveyor - rubberized, steel or mesh belt moving along guide rollers. The main advantage is the ability to load and unload at any point. Cranes are stationary, portable and mobile.
Performance decreases with increasing tilt angle. Maximum slope angles for coal, clay, gravel, limestone - 18 °; for coke, sand, ash, cement - 20 °.
Lamellar conveyors are installed similarly to belt conveyors, but with the replacement of the belt with metal plates. They are used to move heavy rigid loads and loads with high temperatures.
Scraper or bucket conveyors are a fixed chute along which material is moved by scrapers attached to an endless chain or cable. Loading and unloading of material can be done anywhere through the holes in its bottom or cover, closed with special valves. On inclined and vertical sections of the conveyor, the scrapers are replaced by buckets, which in the lower horizontal sections pick up the load, lift it up and there it is poured into receiving devices.
Suspended chain conveyors can have any trajectory.
Closed ring chain conveyors can serve work areas at any level.
Freight conveyors are moving carts with a load located on them. They have a spatial arrangement in the form of a closed curve. They are used in assembly, molding and casting lines.
Elevators are used to lift cargo vertically or at an angle. There are bucket, shelf and cradle. Bucket and cradle lift bulk or small materials; shelf - separate products.
Roller conveyors, or roller tables, consist of a frame, inclined towards the movement of goods, with freely rotating rollers fixed on it with a diameter of 100-150 mm for heavy goods and 65-75 mm for light ones. The inclination of the conveyor depends on the nature and weight of the transported cargo.
Screw conveyors, or augers, consist of a chute, a screw, inlet and outlet nozzles, a drive and support structures. Produce rectilinear, horizontal and oblique movement of various bulk materials: pulverized, powdery, granular and small-sized. They can be from 4 to 60 m in length.
Road transport should be provided whenever possible, taking into account the weight and dimensions of the transported goods.
Conveyor, hydraulic and cable-overhead modes of transport should be used, as a rule, with a continuous supply of materials, finished products
or waste from mining sites directly to the consumer, processing points and dumps.
Continuous transport in domestic transport should be used with constant and significant freight flows between workshops and when transferring bulk cargo from warehouses to workshops.
In this case, it is recommended to provide:
- belt conveyors for supplying coal (to boiler houses of CHP and GGS), ore, concentrate, limestone, agglomerate, bulk materials, etc .;
- pneumatic transport for the supply of bulk materials (molding mixtures, sand, cement, pulverized coal, alumina, fine shavings, catalysts, powdered lime, etc.) and granular materials from warehouses to production workshops, etc .;
- hydrotransportation for moving (cleaning) ash and slag (from boilers and thermal power plants), as well as sludge, granulated slag, etc .;
- overhead chain pushing address conveyors, as well as conventional overhead conveyors with automatic loading and unloading in the form of a single system of intrashop and interdepartmental transport for the transfer of bulk piece cargo (with a sufficient size and constant direction of cargo flow), blanks from blanks to processing shops, feeding units, semi-finished products and parts for assembly lines and finished products for testing;
- pipeline transport for supplying liquid chemicals, oil, fuel oil, gasoline, kerosene, gas from the warehouse to the production shops with their significant consumption.
Railway transport for interdepartmental transportation is allowed to be used only for transportation of hot and heavy oversized cargo, as well as in other cases with a proper feasibility study.
If it is impossible to replace railway transport with other modes of transport, it is allowed to arrange railway inputs into all production facilities, regardless of the category of production facilities located in them. At the same time, the entry of traction rolling stock into premises with production facilities of categories A and B, as well as steam locomotives with a fire chamber (except for locomotives with explosion-proof motors) into premises with production facilities of category Viv premises, regardless of the categories of production located in them, with open combustible coating structures and no overlaps are allowed.
The width of intrashop production passages for roadless transport and the dimensions of the openings of the gates (doors) should be taken depending on the dimensions of vehicles and transported goods.
The height of in-shop production passages from the floor level to the protruding structural elements of galleries and platforms crossing the passages, or to the lowest point of goods transported by lifting and transport devices crossing the passages, must be at least 3.6 m.
If the passage is not intended for the movement of vehicles, the height of the passage can be reduced to 2.4 m.
Indoor railway tracks should be arranged so that the top of the rail heads is at the level of the finished floor. In the absence of trackless transport in the premises and mass movement of people through the tracks, it is allowed to place the rails and the upper structure of the track both below and above the level of the clean floor. In the latter case, in the main aisles, it is recommended to provide transition platforms with a flooring device at the same level as the rail head. The railroad tracks in premises 1.5 m wide from the normal track axis and 0.9 m wide from the narrow track track axis should be covered with floors of an easily disassembled structure.