Exchange rate project for calculation of tower crane

Contents

Introduction of pages

1. Analysis of existing designs of mass-produced machines

1.1.Basic features of the proposed design

1.2. Description of machine operation

2. Design and calculation part

2.1Compute cargo lifting mechanism

2.1.1.Elect rope

2.1.2.Define basic dimensions of blocks and drum

2.1.3.Selection of engine

2.1.4.Selection of coupling

2.1.5.Selection of brake

2.1.6. Engine check by acceleration

2.1.7.Provision of brake by acceleration

2.1.8.Check the engine for heating

2. 2. Calculation of crane movement mechanism

2.2.1. Determination of geometrical and mass characteristics of the crane

2.2.2. Selection of movement mechanism

2.2.3.Selection of engines and running trolleys

2.2.4.Check of engine by torque

2.2.5.Selection of brake

2.3.2.Check of brake by torque

List of used literature

Application

Introduction

Tower construction cranes are designed for construction, installation and loading and unloading.

The tower crane consists of a tower (column), boom, support part, support-turning device, driver's cab, load lifting mechanisms, boom turn, departure change, safety devices (load capacity limiters, load lifting height, cargo trolley movement, boom turning and lifting). All mechanisms of the crane are controlled by the driver from the cockpit, in which the control equipment is located.

According to the design, tower cranes are divided into cranes with a rotating platform and a non-rotating tower. For cranes with a rotary platform, working mechanisms are installed on a rotary platform to which the tower is attached. Cranes with a non-rotating tower, in addition to the main parts, have a rotary tip, to which a counterweight cantilever with a counterweight (counterweight) at the end is attached to balance the rotary part. Cargo and boom winches are installed on the counterweight cantilever.

If possible, the tower cranes are divided into mobile, attachment, stationary and self-lifting.

Support part of movable tower cranes includes running bogies attached to lower frame. In some cranes with a non-rotating tower, running trolleys are attached to the tower through a portal. Running bogies on steel running wheels move along rail crane track by means of crane movement mechanism.

Support part of stationary tower cranes is frame installed on monolithic base. At high height, tower cranes are additionally attached to the erected structure. Such cranes are called attachment cranes. In some cases, an attachment crane up to a certain height can work as a mobile one. Then it is universal and has a support part in the form of a running device similar to mobile cranes.

The change of the departure at the tower cranes is carried out either by changing the angle of inclination of the boom by means of a boom winch and a boom polyspast, or by moving the cargo trolley (carriage) along the boom by means of a pull winch. Depending on the method of changing the departure and type of boom, tower cranes are divided into two groups: with lifting and beam booms.

The tower cranes have a multi-engine electric drive powered by an external network through a cable and a current collector and perform the following movements: lifting the load, changing the departure, turning, and mobile cranes, in addition, moving. The combination of these movements allows you to transport cargo to any point in the working area, as well as service the territory of the warehouse, unload goods from vehicles.

To ensure stability of mobile tower cranes, ballast is laid on a rotary platform or in the lower part of a non-rotating tower.

The advantages of tower cranes are a good view by the crane operator of the installation area, the location of the boom at high altitude, as a result of which it does not cross the structures of the object under construction, simplicity and reliability in operation, large linear dimensions of the working area.

Disadvantages include the need to arrange crane tracks for the movement of cranes, as well as the installation and dismantling of the crane during its relocation.

The main parameters of the basic crane models are regulated by GOST 13556-85, according to which the following designation of tower cranes is adopted: KB20040R - tower crane, load moment 200 t • m (1960 kNm), lifting height 40 m, rail; KB320150P - tower crane, load torque 320 t • m (3136 kNm), lifting height 150 m, attachment.

The indexation system of tower cranes produced by the plants of the Ministry of Construction and Construction is provided with the first digit to denote the number of the three-dimensional group, the second and third digits are the structural features of the crane, the letter is the serial number of the model, the last digit is the modification number. Climatic performance is indicated by the letters: CL - northern, T - tropical and TV - for humid tropics.

Four dimension groups were installed: 3, 4, 5 and 6, for which the crane load torque is respectively up to 980, 980-1960, I960-2940, 2940-4900 kNm. The second and third digits in the crane brand are a number that, in the range from 01 to 70, characterizes a crane with a rotary platform, and 71-90 - with a non-rotating tower. For example, KB674A5 - tower crane, cargo moment more than 2940 kNm, with a non-rotating tower, first model, fifth version; KB401B - tower crane, load moment more than 980 kNm, with a rotary platform, the second model.

Valve KB401 (KB160.2) has lifting boom. When departure changes, the load moves along a trajectory close to horizontal, which is ensured by kinematic connection of the cargo and boom winches. Designed for the construction of multi-storey residential and civil buildings up to 16 floors high. In the usual version, it can work in winter at a temperature of up to - 25 ° C. When using a brake fluid of the AMG10 and PG271 type in hydraulic pushers, the crane can operate at a temperature of up to - 40 ° C. The height of the tower changes by growing as the structure is erected. The load characteristic depends on the number of sections in the tower and the installation area