Topic: General information on lifting equipment. Gantry and semi-cooled cranes

Lecture 1. General about lifting equipment Objective: Explore the appointment and composition of lifting equipment, mechanisms and elements of lifting machines, general information about the cranes. Educational questions: 1. Purpose and composition of lifting equipment 2. Mechanisms and elements of lifting machines 3. Automotive cranes 4. Bridge cranes

Literature: 1. "Rules of the device and safe operation of load-lifting cranes" PB (approved by the decision of the Gosgortkhnadzor of the Russian Federation from G. 098) 2. "Inter-sectoral rules for labor protection during loading and unloading work and the placement of goods" Pot PM (approved by the Decree of the Ministry of Labor and Social Development Russian Federation dated March 20, 1998 16) 3. Fedoseev V.N. Instruments and safety devices for lifting machines: directory. - M.: Mechanical Engineering, - 320c. 4. Navy E.M. Lifting equipment: Tutorial. - Perm: PV RV, p.

Purpose and composition of lifting equipment Lifting equipment is part of Technological equipment and is intended for carrying out loading and unloading, assembly and dismantling work. Lifting equipment includes loading machines (GPM) and shipping devices (GZP). GPM are intended for lifting and moving in the space of various goods. The GPP is used to connect the hook of GPM with the lifted cargo (cargo lines) of the GIM are divided into three groups: the simplest lifting machines (jacks, winches, hoists), lifts, lifting cranes (boom and bridge types) GZP can be divided into two groups: removable shrouded On the hook of the crane, and removable, fixed on the lifted cargo. GZP are not accessories of GPM and are independent products of repeated use

Jacks are designed to raise goods for a small height (up to 1.0 m). Used in repair and installation work. The jack drive can be manual or machine. According to the type of mechanism, allowing to obtain a power gain, the jacks are divided into screw, robes, hydraulic and chamber jacks: A - screw: 1-nut; 2-screw; b - wheels: 1-gear rail; 2-gear associated with a handle; B - hydraulic: 1-plungers; G - Chamber: 1-fitting compressed air from compressor, cylinder, foot pump

Winchs are designed for rectilinear movement of goods. The lifting winches used for the vertical lift of freely suspended cargo, and traction, which serve to move the cargo or truck with a cargo in the horizontal direction of the winch: A - Tract: 1-actuator; 2-drum; 3-rope; 4-load; b - lifting: 1-actuator; 2-drum; 3-rope; 4-load; 5-deviating block

Tali is lifting suspended winches. Mobile hoists are equipped with movement mechanisms on suspended paths. The hoists are part of the crane beam as a cargo lifting mechanism. Tali: A - manual: 1-beam; 2-manual winch; 3-chain; B - mobile electric: 1-beam; 2-electric winch

Lifts are load-lifting devices of cyclic action for lifting goods and people in special load-rigging devices (centers, cabins, platforms) Lifts: A - Mine: 1-winch; 2-cab (crate); 3 mines; B - rack: 1-deviating unit; 2-cargo platform; 3-rack; 4-winch

Lifting cranes These are load-lifting cyclic action machines intended for lifting and moving in the space of various goods suspended with the hook. These are the most common GPM, having a very diverse constructive performance Classification of lifting cranes

The main mechanisms of lifting machines The functional purpose of the GPM is to move the cargo from one point of the workspace to another. It is quite obvious that for this, the GPM should be able to move the goods according to three mutually perpendicular directions, i.e. Have three portable degrees of mobility of the shipping organ (hook). In arrovar cranes, this is achieved by the load-lifting mechanism (MPG), a mechanism for changing the arrows (MIVS) and the mechanism of rotation of the platform (MPP). In the bridge cranes, the three portable degrees of hook mobility are provided by the cargo lifting mechanism (MPG), the movement mechanism of the bridge (MPM) and the movement mechanism cargo truck (MPGT) The degree of mobility of the shipping organ: a - boom crane: 1 - arrow; B - bridge crane: 1 - cargo truck; 2 - Most

Structural schemes of the mechanisms of lifting machines Structural scheme: A - MPG and MIVS: 1.3 - brake; 2 - engine; 4, 6-couplings; 5 - gearbox; 7-drum; 8 - cargo (boom) polyspaster; B - MPP: 1 - brake; 2-engine; 3, 5 - couplings; 4 - gearbox; 6 - gear; 7 - gear crown of the reference circle; B - MPM and MPGT: 1 - brake; 2 - engine; 3, 5 - couplings; 4 - gearbox; 6 - running wheel; 7 - Rail

Elements of lifting machines are loading organs, steel ropes, blocks, hook suspensions, polyaste. The airproof organ is the device for hanging, capturing the cargo. The largest distribution received freight hooks hooks hooks: A - single-legged: 1-shank, 2-fused lock, 3-eyed hook; b - twiny

Polyspast is a system consisting of moving and stationary blocks enhanced by a rope. The block whose axis moves in space, is called mobile, and the unit whose axis does not move in space - fixed. There are freight and boom polyspars. The cargo polyspast is part of the MPG, and the boom - in MIVS polyspers: a - single: 1-rope; 2-drum; 3-fixed part of the GPM design; 4-cut drum; B - dual: 1- rope; 2-drum; 3-equation block; 4-counter cutting drum

The main parameters of automotive cranes are the values \u200b\u200bthat characterize the technical capabilities of the departure of the arrow L - the distance horizontally from the axis of rotation of the rotary part of the crane to the center of the throat. The magnitude of the departure is inconsistent, it depends on the length of the boom and the angle of tilt the height of the hook Hook - the distance from the level of the crane parking to the center of the hook in the extreme upper position. N value depends on the length and angle of inclination of the arrow The depth of the hook H - the distance from the level of the crane parking to the center of the throat of a hook in the extreme position

The speed of lifting and lowering the load - the speed of vertical movement of the load landing speed - the smallest rate of lowering the maximum admissible cargo When installing or laying the speed of rotation of the rotary part - the speed of the rotary part per unit of time The working speed of the crane movement is the speed of movement of the crane on the working platform with the boom equipment, which is in the working position, and with a suspended cargo, if movement with a load on the hook cargo vehicle Crane movement - the speed of movement of the crane, the boom equipment of which is in the transport position The total mass of the crane is the mass of the crane with the boom equipment and the counterweight with full fuel refueling and lubricant materials The main dimensions of the crane: the greatest length, height, width and distance between remote supports. dimensions Determine the possibility of working and movement of the crane in crane conditions

The diagram of the two-bang bridge crane of the reference type two-bit pavement crane type: 1 - main beams; 2 - end beams; 3 - separate drive of the moves of the transport mechanism of the bridge; 4 - cargo truck; 5 is the main mechanism of lifting cargo; 6 - auxiliary cargo lifting mechanism; 7- mechanism for the movement of the cargo truck; 8 - control cabin; 9 - trolls; inspections 10 - cabin for trolls; 11 - flexible electrical cable; 12 - Wire Holding Electric Cable

See also:
• Bratykov D.E., Orlov A.N. Special lifting machines (document)
• Special lifting machines. Portal, ship and floating cranes (document)
• Currency Project - Bridge Crane (Course)
• Navar Yu.V. Load lifting machines (document)
• Alexandrov M.P. Load lifting machines (document)
• Alexandrov N.P., Kolobov L.N., Lobov N.A. and others. Lifting machines (document)
• Kuzmin V.V. Calculation and design of vacuum machines and installations (document)
• Savitsky V.P. Lifting machines (course design) (document)
• RTM 24.090.32-77 cranes lifting. Steel structures. Calculation Methods (Document)
• Course project - Crane with swivel tower (exchange rate)
• Zeldovich E.A. Romayor Machine Design and Maintenance (Document)
• Abstract - lifting machines. Bridge cranes (abstract)

n1.DOC.

Technological lifting machines.

Chapter 1. Overview of the designs of lifting machines.

§one. Lifting machines with flexible cargo suspension.

Advantages.

1. 
   The possibility of lifting the cargo to a very large height.
2. 
   Steel wire ropes are used as a flexible cargo element. Rope, being a elastic element, softens the loads of the load.
3. 
   The mechanism of lifting the cargo can be completed, largely from standard and normalized elements.

1. 
   The need for rigging operations (mooring and swinging the cargo).
2. 
   When horizontal movement, the cargo swinging onto the rope, therefore, an increase in the time of acceleration and braking and reducing the movement rate is necessary.

1. Tali.

Figure 1.1, and is one of the options for the Tali design,

but
In fig. 1.1, b - appearance Tali.

but)

From the electric motor 1, rotation is transmitted through the coupling 2 to the speedless shaft 4 of the gear cylindrical two-stage coaxial gearbox and then through two pairs of gear wheels 15.10 and 8.9 to the cable drum 13. The drum 13 is installed in the housing 5 of the thaw on two radial bearings 3 and 6 . When rotating the drum in one side or another, the rope 12 is wound on the drum and raises the hook suspension 7 or watched from the drum and lowers the suspension. At the right end of the shaft 4, a disc brake is installed 11. The Tal is suspended to the trolley 16, which moves on the wheels 14 along the suspension of the heated beam17.

1. Stationary rotary cranes.

2.1. Wall swivel cranes.

Fig.1.2.1-stubborn bearing; 2.4- radial bearings; 3-metal constructions of the 5-column of the crane; 6 - Lifting mechanism; 7 - rope; 8 - deflecting unit; 9 - hook suspension; 10- Handle for turning the crane.

Column 5 crane is installed in two supports. The lower support is combined with radial 2 and resistant 1 bearings, and the upper support is floating with radial bearing 4.

Usually self-aligning bearings are used in the supports of rotary cranes, capable of compensating for the inconsistency and mutual skewers of the axes of the planting holes in the supports of the supports.

Figure 1.3 shows a wall swivel tap with a bulk type metal and variable departure. On the metal structures 1, Tal 2 moves.

Fig.1.3.

2.2. Cranes with a rotating column.

Figure 1.4 shows a crane with a rotating column 7 welded with an arrow of the beam type 9. The tal 10 moves on arrows 9. The lower support of the column 7 is made combined with radial 11 and resistant 12 bearings, and the upper support is floating with radial bearing 8.

The turn of the crane is carried out by a mechanism consisting of an electric motor 1, couplings 2, brakes 3, worm gear 13, a safety clutch 5 and an open gear of 4, 6. The gear 4 is installed on a low-speed shaft of the gearbox 13, and the gear wheel 6 is on the column 7.

Service area for a full-turn crane is a ring, for non-pervert - part of the ring.

2.3. Cranes on a fixed column.

Cranes are with a constant and variable departure, with the metal structures of the truss and beam type, full-turn and non-filler; Turning is carried out manually or mechanisms.

Figure 1.5 shows a crane on a fixed column with a constant departure and with metal structures of a beam type. The metal structure consists of a rotating column 7 and bonded with a beam boom 10. Metal structures relies on fixed column 6.

The upper support is combined with radial 9 and resistant 8 bearings, and the lower support is floating with a radial bearing 5. Much more often the lower support is performed in the form of rollers rolling along a fixed column 6.

The turn of the crane is carried out by a mechanism consisting of a gearbox 1, a safety clutch 2 and an open gear, including gear 3 and a gear wheel 4. The gear gear is installed on the output shaft - gearbox 1, and the wheel 4 - on the column 6. Service area for A full-turn crane is a narrow ring, for incomplete - part of a narrow ring.

1. Bridge cranes.

3.1. Single bull taps with stall (faucets).

The main beam 2 (2-way) was welded with two end beams 1. The main beam moves the electrode 3. The crane itself moves along the workshop on wheels 5 by rails 4. Service area is a rectangle, stretched along the workshop.

3.2. Electric bridge cranes.

3.3. Gantry and semi-coal cranes.

§2. Lifting machines with rigid cargo capture.

Advantages.

1. 
   Lack of rigging operations, because The load is captured by a special grasp, and the operator controls the machine from the remote.
2. 
   With horizontal movement, the cargo does not swing.

Figure 1.7, and shows a rotary hydraulic crane. In a fixed column 4, a rotating column is installed 5. The upper support of the column 5 is made combined with radial 6 and resistant 7 bearings, and the lower support - floating with radial bearing 3. A variant of the top support with one radial-resistant bearing is possible.

From the hydraulic motor 1, the rotation is transmitted via the coupling 2 of the column 5. The booming of the boom 9 performs the hydraulic cylinder 8, the cargo capture is grabs 12, and the vertical movement of the cargo is a telescopic hydraulic cylinder 11. When the boom is swing 9, the hydraulic cylinder 11 deviates from the vertical position. To eliminate this disadvantage, auxiliary hydraulic cylinder 10 is used, the work of which is coordinated with the operation of the hydraulic cylinder 8 in such a way that the hydraulic cylinder 11 is always in a vertical position. The vertical position of the hydraulic cylinder 11 can be ensured by performing an arrow 9 as a pantograph (Fig. 1.7, b.).

Figure 1.8 shows a mobile hydraulic crane.

The main beam 1 of the boxed section was welded with two end beams 2. On the main beam on three pairs of rinks 3, 6 and 7, the carriage 4 moves. Vertical move The cargo carries out a telescopic hydraulic cylinder 5. The crane itself moves along the wheels on wheels 9 by rails 8.