When referring to cranes and maneuvers that are carried out to assemble, disassemble and hoist a tower crane must comply with the protection and safety manuals; adhering to strict control in each of the steps to be taken.

Crane tower assembly

Once the components of the tower crane have been unloaded on the construction site, it is assembled.

This process consists of erecting and mounting the crane on its site and foundations, in such a way that it can be able to provide the function for which it was designed.

Assembly required

The assembly and disassembly personnel must respect all the recommendations contained in the manufacturer’s manual, which must be complemented with the instructions given in writing by the professional responsible for the assembly (university professional or technician with experience in the assembly of tower cranes). Special care must be taken with prevailing weather conditions.

The written order emanating from the professional in charge must contain at least the following information about the crane:

• Brand, type and model.
• Mounting heights, initial and final, expressed in m.
• Pen and counter-feather length expressed in m.
• A number of elements, position, dimensions, and mass of the necessary air counterweight.
• Characteristics of the initial and final weights (geometry, dimensions, mass, and ordering).
• A number of branches of the lifting cable.
• Supply voltage and a section of the conductors.
• The bracing program, if applicable, in case the height of autonomy is exceeded.

How are cranes set up?

Stability Conditions:

With regard to the fact that the cranes and maneuvers need stability conditions, before starting the assembly of a tower crane, the following must be done:

A study of the soil mechanics of foundation.

The construction of the basal ballasts and aerial counterweights according to the technical specifications of the assembly manual can be metallic, concrete or bulk materials, in which case they must be contained in a closed and sealed metallic box.

The counterweights and ballasts formed by blocks must bear a mark printed in easily legible and indelible characters, indicating the mass of the same. Each time the crane is assembled, the mass of the counterweight to be used must be verified, and these must always be secured to the structure of the tower crane.

The correct construction of the anchors and their consolidation.

The construction of foundations that adequately transmit maximum gas to the ground, these must be calculated and designed by competent university professionals.

The rails and other elements that are part of the road must be installed according to the provisions of the manufacturer, the fastening of rails must be appropriate to the materials of the structure that supports them.

Tower crane safety precautions

For the use of cranes and maneuvers, the tolerances admitted in the initial installation of the straight and horizontal roads will be the following:

Longitudinal leveling: The surface of translation of the same line of rails, must not present irregularities of a level higher than 1/1000 of the width of the track.

Transverse leveling: The difference of the height between the two lines of rails of the same track, should not be greater than 1/1000 of the width of the track.

How to build a tower crane?

Distance between axis:

The gauge and the tolerances must correspond to those specified in the manuals of the crane manufacturer, the head of each rail must be between two parallel vertical planes, whose separation is equal to the nominal width of the said head plus 5 mm.

• The slope between rail joints: Must be 2 mm maximum
• Separation of rail joints: Determined according to the dilatation calculation of the rail
• Transverse leveling of the foot of each rail: It should be 3 / 1,000 maximum, with respect to a horizontal plane
• State of the track of translation: The flat surface of the head of the rail, must be centered with respect to the plane of symmetry of the same.

Rolling tower cranes must have adequate means of immobilization to avoid any movement when exposed to the action of the wind. These means must be established according to the specifications contained in the manufacturer’s manuals.

Tower crane jacking process

Assembly Procedure:

In general, the process begins with the assembly of the base of the tower, then the first section is placed, with the diagonals that join it to the base and a part of the basal ballast, then the slide is installed on top of it. locate the tower head and the cabin.

Then the pen and counter jib are placed. The final counterweight is mounted and more basal ballast is added. New sections are installed with the help of the boom of the crane until reaching its final height.

Another way to increase the height is by means of a system in which the tower-cabin-head unit is smaller in section than the rest of the shaft. The new section that has an open side is superimposed on the tower surrounding the upper unit.

Then it goes up inside this new section, newly armed.

Steps for the assembly of a tower crane

• After the assembly of the cart and the basal ballast, the climbing equipment is prepared.
• The climbing equipment is mounted on the base section of the tower.
• The rotating part is assembled, including turning track, cabin, tower head and climbing section, joining the assembly tower.
• The counter jib is placed.
• With the hook of the crane, the tower section is placed on the mounting crosspiece.
• The elements of the climbing system. The assembly tower, the hydraulic equipment, and the support sleeper

The assembly systems have improved remarkably over time, in order to make it faster, more comfortable and simpler, thus reducing the cost of this operation.

The assembly of all the assemblies is done by means of quick joints that do not require the previous alignment.

In addition, the climbing is done by the hydraulic drive and the operators perform all their work from safe and robust platforms, making the whole process even in large capacity cranes very fast.

Operating conditions

Forms of Operation: There are basically three possibilities of operating a tower crane:

• Through keypad
• Joystick
• Using joystick built into the command chair

The first two systems allow remote operation; that is to say; they allow the operator to move to the same point where the work is done, thus achieving greater security in a certain operation.

Usually, when visibility permits, it is operated directly from the command cabin, moving either the keypad or command box of it. And with the help of the signalman, it is possible to make the required movements.

The lever command systems indicated above have the following operating movements:

• Start-up of the crane
• Warning horn
• Load upload (First, Second and Third speed)
• Lowering of load (First, Second and Third speed)
• Translating the distributor car forward (First and Second Speed)
• Translation of the distributor car backward (First and Second speed)
• Turn to the right (First and Second speed)
• Turn to the left (First and Second speed)
• Translation on rails forward
• Translation on rails backward
• Emergency stop

Crane operator

The operation of a tower crane must be carried out by a person who duly certifies his professional capacity. Requirements to be a crane operator:

The operator of a tower crane must have a basic knowledge of the assembly, operation, safety and maintenance conditions of a tower crane, as well as the knowledge necessary to interpret the manual and other technical documents provided by the manufacturer of the tower crane, to enable it :

• interpret a load chart
• know clearly the importance of the safety mechanisms of each crane
• its function and its normal location
• know the importance and behavior of steel cables and know how to put the crane into service correctly.

It is recommended that the handling of the crane is only entrusted to people over 18 years of age, who have a minimum level of schooling, who have passed a psychometric test, equivalent to the driver class A2, absence of diseases incompatible with work, have a high degree of vision and hearing, insensitivity to vertigo and good reflexes.

They must also attend a training course (in Operators and Requirements and responsibility, it was established that the operators that have more than one year of duly accredited professional experience, will be able to opt for the corresponding training or professional accreditation of 25 hours and the operators 25 that have been started after 1999 must attend a course of 150 hours, after which they will obtain a card) and undergo periodic medical examinations (worrying exams).

Crane operator responsibilities

At the beginning of the working day, the operator must make and record the following verifications:

• Check that the rails are aligned and correctly secured.
• See that the road is free of obstacles.
• Control the consolidation and alignment of the basal ballast and the counterweights.
• Observe possible oil leaks in the gearboxes.
• Check the operation of the controls of the tower crane, operating it without load.
• Check the good condition of the travel limiters of the carriage and the hook.
• Check the condition of the steel cables.
• Verify the proper functioning of the safety lock of the hook.
• Verify that the handle of the straps has not suffered wear or deterioration in the weld
• that the components of the closing of the gate of the mats work correctly, verifying especially, the absence of round fluted construction iron in any supporting element.
• Verify that the flanges do not have cuts or other damages.
• Inspect the metal structure to detect possible bends or deformations of its components.
• You should worry about the order and cleanliness of the cabin, the walkways, the ladders, and the rails.

In case of any anomaly or damage, the crane operator must stop the tower crane and immediately inform his superior.

During the execution of the entire work, a daily report must be kept in which the time worked and the operational news is recorded.

Crane operation safety

When the conditions of vision are not optimal for the operator, he must obligatorily request a signalman to the work for the help of the cranes and maneuvers.

The signalman must know the international code of signals for the operation with tower cranes, which is based on indications with hands and arms.

The signals of this code are regulated by the Tower Cranes Standard. Operating conditions and to be directly understood with the operator of the tower crane.

This code is formed by simple signals, easy to execute and interpret and that also does not produce physical exhaustion since the movements are natural and logical.

Crane safety procedures

Signal Technique: When crane and maneuvers are used, the technique of these signals is mainly based on the following:

• A hand on the waist indicates working at normal speeds, in any maneuver.
• A hand on the chest indicates working at slow speed, in any maneuver.
• The two hands up to indicate normal stopping.
• The two hands on the sides mean stop immediately.
• All signals must be executed calmly and safely, any doubt or acceleration of a signal will only confuse the operator.
• The signalman must be careful to always be in sight of the operator of the crane.

Crane safety signs

The signals that are normally used are:

• I take the command.
• Upload normal.
• Upload slowly.
• Download normal.
• Normal right turn.
• Right turn slow
• Truck on the right with normal speed.
• Truck on the right with high speed.
• Normal detention
• Car on the left with normal speed.
• Car on the left with high speed.
• High of urgency.
• Change of branch.
• End of command.

In important works, it is also recommended to have a radio communication system, to complement the corresponding orders to the operator as far as the tasks to be done and their correlative order; in this way, the isolation is avoided when the operator works in the cabin.

Tower crane safety

Interruption of work: The cranes and maneuvers, are very sensitive to the wind and whenever this exceeds the speed of 64 km/hr, or even if the wind has a lower speed and loads of large surface are handled, the work must be paralyzed, leaving the pen in ” weathervane “, so that it does not resist the wind and, therefore, its overturning does not occur.

The work of the crane must be interrupted in the face of adverse weather conditions such as presence of frost, when it represents an overweight due to accumulation in the structure or hinders the descent of the hook when it is empty; also when there is no good visibility due to the presence of fog and the proximity of an electrical storm.

Reasons: The work of the crane must also be interrupted by anomalies in the installation or in the operation, such as:

• A bad condition of the lifting cable or flanges.
• The poor winding of the lifting cable in the drum.
• Intermittent power supply and/or loss of phase symmetry.
• Defects in the braking operations of some movement of the crane.
• Loss of lead in the structure.
• Lack of adequate lighting.

Tower crane maintenance

Maintenance work must always be carried out with the crane disconnected. Maintenance work that can not be carried out from the ground, must be done from scaffolding or appropriate platforms.

If the maintenance work can only be carried out with the crane in operation, it must be ensured that:

• There is no risk of a person being trapped or falling.
• The people who must carry out this work move away from elements through which the electric current passes.
• These people can communicate with the crane operator by word or by means of signals.

Tower crane safety checklist

Verifications:

The cranes and maneuvers that are made with electrical energy must be verified by a specialist before the first putting into service or before being put back into service after having been subject to major modifications. Cranes with a load capacity greater than 1000 Kg must also be verified.

The verification prior to the initial commissioning of a new crane is not necessary if the crane has already been verified beforehand and is accompanied by the corresponding documentation.

According to their own characteristics and local circumstances, the cranes must be checked by a specialist at regular intervals, but at least once a year. In addition, tower cranes must be inspected by authorized persons whenever they are assembled or when their characteristics change.

Registration of verifications The results of the verifications according to the above must be recorded in a verification book that can be consulted at the request of the researcher.

Maintenance costs have always been a concern and progress is being made on a continuous basis in the reduction of lubrication points and in the placement of materials that allow space to be maximized in maintenance operations and incorporating components that do not require maintenance.

Tower crane disassembly

To start the dismantling of this crane we must first have the right personnel to carry out this work, that is to say, that each person has the relevant safety talks, safety elements, and work disposition.

Once the supervisor has checked the conditions of the ground, you can determine with what support crane you should proceed to do this work considering the height and the radius.

Once you have all the aforementioned, the first thing to do is to dismantle the tower crane the number of sections, which are necessary for the reach of the auxiliary crane.

With the lifting cable of the tower crane, the pass must be made that allows the aerial ballast to be removed. Depending on the length of the boom of the tower crane, a ballast is left or not in the counter boom.

Then the lifting and carriage cables are removed to leave the boom released from these elements, then the passes are made with the lifting cable between the boom and the turret.

Crane outrigger safety

Auxiliary crane:

With the cranes and maneuvers you must have an auxiliary crane, that the pen has to be locked in the points that allow the balance of this piece, when it is fully in the air it must be hoisted a bit with the auxiliary crane in such a way, that it releases a little the traction exerted by the piece due to weight effect.

Then with the lifting of the crane must be tensioned to remove the pins that join the strut of the pen with the turret, achieved this lowers the elevation until the strap is completely housed on the back of the pen, at that time you can remove the fastening pins.

So that the feather is totally in the air, ready to lower it to earth, and in this way make its subsequent disarming and loading on trucks.

Disarmament and carriage

Then the air ballast should be removed according to the length of the pen should be left, so that this serves as a counterweight before removing the pen, then removed the counter-feather, stroking this piece with the auxiliary crane stands up to remove the pins of the braces and then remove the pins of subjection of the counterjib, and take it to earth for its later disarming and loading.

After the turret was broken in the upper part, the connecting bolts of sections are removed and this piece is ready to take it to earth.

Next, the scaffolding and the hydraulic pump must be removed from the center of the tower, then the track seat or cabin section of the upper part must be damaged, the bolts must be removed, and this piece must be grounded. After this, the tower sections can be removed according to the need and capacity that is required at that moment.

Now we proceed to remove the basal weights, if the tower crane is in the simply supported version, then the diagonals are removed joined by a pin at each end, this way the basal section is left free, to remove this piece and able to carry out the dismantling of the chassis that is also joined by tower connection bolts.

Finally, the connection is made from the earth that is usually on one side of the crane chassis, an evaluation of the work is made and a report is finally drawn up for this work.

Applications of cranes and maneuvers

There are different systems and sizes of cranes and the technical requirements that these cranes must meet are not the same in all countries.

The most commonly used cranes are the quick application cranes that move as a compact unit and can be assembled without the need for other auxiliary means.

Tower crane manufacturers

Tower cranes in the world:

• Europe and Germany represent the largest construction market.
• In Southeast Asia and the Far East market, almost exclusively turntable cranes with needle boom or articulated boom are used almost exclusively.
• In the construction of tall buildings, telescopic cranes are preferred, since in this field it is almost impossible to use a tower crane and its complicated assembly is not so relevant since labor is less expensive in this region.

How do you assemble a tower crane?

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In the distance, you can see these huge loading machines, very similar to each other and fulfilling the same function; be combined vertical and horizontal transport equipment, however, when looking at them carefully, it can be verified that in fact, the types of tower cranes are very different from each other.

Types of construction cranes

Classification of tower cranes: How many types of tower cranes are there and what are they? Due to the reach and height, they can develop they are used a lot in the construction of tall structures. Tower cranes can be classified according to:

The way it is assembled

Automatic Crane

Automatic Crane (GA): It is the one that comes with its folded tower and boom, with the separated cable runs, with their counterweights generally placed. You just have to level it, deploy it and at the time it is armed, it can be calibrated.

Tower crane: It is one that is assembled by sections, helped in its first part by a motorcycle crane. Then we continue adding cloths through an assembly operation.

Mobile Tower Crane

It is the combination of the previous two and in addition, you can add some sections. The use of this type of cranes in the construction of small heights and open spaces has already become very popular.

Generally, small capacity models have been used. Nowadays, however, there is a wide range that includes cranes up to 140m / t.

These cranes are easily portable since they can be sent as compact units in a trailer, with their counterweights, even large capacity ones.

This type of cranes has incorporated the possibility of climbing to achieve greater heights of employment, so that the advantages of a rapid movement from one place to another, is added the possibility of using them in higher constructions.

The development trends of these cranes have been aimed at achieving greater possibilities of installation and assembly that can be summarized in the following:

• Easily save obstacles such as antennas, chimneys, and adjacent buildings, by using the crane by raising the boom at an angle of 45º.
• Reduce the radius of rotation of the base by modifying the design of the base and the counterweights.
• Allow the assembly of them boom to be carried out in increasingly reduced spaces by means of joints and folding of the same.
• Achieve higher heights through simple and fast climbing processes.

For the form of support of the crane

Rolling Tower

It is the crane model most used for the construction of blocks of apartments and in buildings of isolated towers, they allow to move the crane with a load on a previously studied and installed on-site road. Given the importance of the routes of translation for a good performance of these teams, it is convenient to respect all the security measures that are adopted in these cases.

Fixed Tower Crane

In this version, the crane is located static at a point, on a chassis and distributed in the circle area encompassed by the boom. The assembly of this lifting equipment on site can be through the following procedures:

The embedding of a concrete block of dimensions according to the resistance of the ground and the weight of the ballast. Normally this solution is used in those works where the crane chassis cannot be assembled, due to lack of space. In general, its height of autonomy decreases.

On the base chassis, without wheels, resting on a resistant slab, with convenient base ballast.

Bolted the base chassis to some slab or beams of adequate strength. In the case of cranes of climbing version, on their frames or rings conveniently fastened to the floors.

Crane climbing

It is a mounting system that allows the tower crane to increase in height by moving inside the building as it increases in height. All its horizontal and vertical loading efforts are transmitted to the building through supporting structures.

This type of system has a drawback in its disassembly, which is slower because it is done on the terrace of the building, which is generally of variable geometry, in this area you have to anchor the equipment necessary for disassembly, which must be calculated and designed in advance. Nowadays this type of fixed tower crane is little used.

Stationary crane

Crane Tower Anchored to the Building or Braced:

When a tower crane exceeds its rolling height determined by its stability, in work and out of service, exposed to excessive wind speed, it is necessary to secure it, anchor it, if the crane is close to a building, and braking it by means of winds if The crane is in a clear work.

Tower crane truck

This type of crane, a combination of an automobile crane and a tower crane, represents a practical alternative to the conventional truck crane since the advantage of the higher starting height of the boom is added to the same speed of transfer between different work points. that has the incorporation of the crane.

By the shape of the Crane boom

Horizontal boom tower

Currently, tower cranes of 4000 m / t are available, which can operate with freestanding heights of up to 300 m. A crane of this size can lift 37 tons at a radius of 80 m and its maximum load is 80 tons. Even modern engineering allows installing a second auxiliary crane on the counter jib of these giant cranes.

Tower crane with articulated boom

This type of crane allows varying the geometry of the use of the boom, being able to be used in a horizontal position, obtuse angle, and straight.

This characteristic makes them especially suitable for certain constructions, such as cooling towers and TV towers. Its design allows maximum height and a smaller number of bracing for similar towers.

Tower crane with a folding boom

This type of crane is especially suitable for use in narrow areas and in areas where there can be no interference between installed cranes. The possibility of moving the jib between angles of 15º and 70º allows clearing the obstacles of its radius of action in a very simple way.

Concreting towers

As a variant of the use of interest, this application can be pointed out, since by eliminating the jib and the counter-feather from the standard models, there remains a rotating mobile tower in its upper part.

Adapting to this set a concrete pump, it is possible to unite for the distribution of the concrete, the advantages that concur in the two means employed. Even this variant of use is possible using the crane in the double application, as a tower crane, and as a support for the concrete pump.

City Crane

Crane city “City Crane”:

This type of cranes is being used especially for the construction work in places already built, such as in the renovation of buildings in the old areas of the cities, close blocks to each other, restoration of facades, timbered historic buildings.

Cranes are needed with a technology capable of solving the specific problems of this type of construction and for example are: little space between the building and the street with a very small sidewalk, very narrow streets, mounts to be made in courtyards, elevator shafts or opposite side of the street and this with additional difficulties such as traffic cannot be closed completely or for a very short time, floors with low capacity to support loads, etc.

These cranes are specially designed to be assembled with a very small number of sequences and must offer the following basic characteristics:

• The base that occupies a small space and that is also capable of supporting the loads per corner to which they must be subjected. These bases usually have a cross shape and should be easily convertible into a cart to install on track.
• Towers of the reduced and compact section to allow their installation in very small holes and to save transport space

By the way of Giro

Crane Tower of the basal turn

It is the one in which the turn occurs in the lower part. Its height is limited.

Tow crane Tower top

It is the most frequently used, its rotation occurs at the top and allows to achieve a greater height.

The constant demand for this type of cranes has produced a considerable advance in the techniques of drive and control. The application of display systems in relation to electronic function packages and system solutions has brought with it, new dimensions for performance and safety.

How do cranes get to the top of skyscrapers?

Tower Crane Pictures

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The tower crane is composed of several parts that are fundamental to perform the work in the construction of a work, these parts are:

Tower crane mast

It is a metal lattice structure with a normally square section, whose main mission is to provide the tower crane with sufficient height.

Normally it is formed by lattice modules that facilitate the transport of the crane. For assembly, these modules will be joined by screws, all of which will be connected to the projected height. Its shape and dimension vary according to the necessary characteristics of weight and height.

In the upper part of the mast is the rotating are which gives the crane a 360º horizontal movement. Also depending on the model, you can have a cabin for its operation by an operator.

Tower crane jib

It is a metal lattice structure of a normally triangular section, whose main mission is to provide the crane with the necessary radius or range. It is also called a jib. Like the mast, it usually has a modular structure to facilitate its transport.

To move the specialized personnel during the assembly, revision, and maintenance work along the jib, there will be a longitudinal element, a safety cable, to which the safety belt carabiner can be attached.

Tower crane counter jib

The length of the counter-jib oscillates between 30 and 35 of the length of the pen. At the end of the counter-jib, the counterweights are placed. It is attached to the mast in the area opposite the union with the jib.

It is formed a robust base formed by several metal profiles, forming on them a kind of catwalk to facilitate the passage of personnel from the mast to the counterweights. The sections of the profiles will depend on the counterweights that will be placed.

Tower crane counterweight

They are structures of concrete prefabricated that are placed to stabilize the weight and inertia that occurs in the jib of the crane. They must stabilize the crane both at rest and in operation. Both these blocks and those that form the ballast must have identified their weight legibly and indelibly.

Tower crane ballast

It can be formed by a buried shoe or by several pieces of prefabricated concrete at the base of the crane.

Its mission is to stabilize the crane against its weight, the weight it can transfer, and the adverse environmental conditions

Tower crane trolley

It consists of a car that moves along the jib through some lanes. This movement gives the necessary maneuverability in the tower crane. It is metallic so that it supports the weight to be lifted.

Tower crane hook

The lifting cable is one of the most delicate parts of the crane and, to give an adequate performance, it must be used and maintained correctly.

It must be perfectly tensioned and a periodic follow-up will be carried out so that, during its winding in the drum, it does not cross over, as it would cause crushing.

Operator Cabin

The movement of the crane is controlled from the operator’s cabin. Within the cabin, you’ll find the operator’s chair with joystick controls, electronic monitoring devices, and communication systems. Many cabins come with climate control to ensure a comfortable work environment. The operator cab is part of the slewing assembly.

Slewing Ring

The slew ring drives the rotational movement of the slewing unit (jib, counter-jib, cab, and tower top). Powered by the slewing gear drive, the slew ring is fixed to a ball track and is made up of several hundred precisely machined gear teeth. The slewing ring is capable of enormous torque, yet precise movement.

Tower crane erector

Top Climbing Unit

The top climbing unit is an essential piece of any tower crane. It enables tower crane sections to be inserted and connected to the tower. A large hydraulic jack then lifts the Slewing Assembly, Jib, and Counterjib one tower section higher. Another section can then be inserted. The top climbing unit adds tower sections to the tower crane; the bottom climbing unit keeps the tower at the same height but raises the whole crane up, repositioning it at a higher point inside the building.

Bottom Climbing Unit

Climbing inside buildings is made possible by the bottom climbing unit. Climbing collars are used with a hydraulic power pack to lift the tower sections upward. The crane is completely supported by the structure of the building it is constructing. This leaves the lower levels of a building accessible for finishing work.

Bolts and Pins

Secure connections are an essential component of any tower crane. Anchor bolts must be of high tensile strength and pins and other bolts should be routinely re-torqued according to manufacturer specifications.

Tie-in

A tie-in secures the tower mast to a structure or framework and provides stability when the crane is under load or experiencing wind forces. The number of tie anchors is calculated by taking into account such factors as the type of crane, jib length, height under hook, and maximum out-of-service wind speed.

Tower crane spare parts

Parts of the tower crane that need spare parts and maintenance:

• Fixing Angle For Tower Crane
• High-Quality Tower Crane Spare Parts Anchorage Frame
• Tower Crane Slewing Control Panel
• Mast Section
• Tower Crane Trolley Control Panel
• Tower Crane Hoisting Control Panel
• Crane Travelling Mechanism
• Tower Crane Trolley Mechanism
• Tower Crane Hoist Mechanism

Tower Crane Costs

Costs vs Savings: Tower cranes are expensive, but when used properly, they can save contractors 50% of their material-handling budget. When compared to mobile cranes, a popular alternative, tower cranes offer a significantly wider radius and easier, compact placement.

For contractors who cannot afford a tower crane, these cranes are also available to rent.

Tower Crane Safety

Operation & Safety: Tower cranes regularly come under scrutiny due to their large size, perch, and prominence in the construction field. This scrutiny is especially heightened after accidents and other incidences. Many of these situations typically involve equipment defects, and inadequately-trained crane service personnel or operators.

Scrutiny needs to be handled proactively through safe, and informed operational procedures, like having an extra man on hand to avoid tower crane collisions when more than one crane is present. Another preventative safety measure mandates crane service personnel to be properly trained to recognize defects, damage, and other hazardous potentialities.

Anchoring

Anchoring & Training

Most all cranes are heavy, but tower cranes are specifically top-heavy. This top-heavy structure requires precise, strong, and well-maintained anchoring to a steady foundation. In order to keep this anchoring secure, the crane operator must be well-trained and experienced, as jerk movements, side and shock loading, fast swinging, and abrupt stopping can all cause the crane, anchor, and concrete to prematurely wear due to stress.

Tower Crane Repair

Repair & Maintenance: Crane service maintenance and repair are often looked at as a troublesome expense when they should be considered a cost saver. If you’ve ever had a tower crane break down or been involved in an accident, then you understand why. Finding fully-trained technicians who know to spot defects before they happen, who know which tools to use, and who can properly inspect their welds, is much easier said than done

What are the Parts of a tower crane and their functions?

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Self-Erecting Crane: Self-erecting tower cranes have long been commonplace in Europe. Their versatility and reliability have made them a mainstay on the European Jobsite. That same versatility and reliability are now practical for the Canadian market. Roblin Crane Services can provide you with self-erecting cranes for all your lifting needs.

Self erecting cranes

Self Erecting Crane: What Is a Self erecting Tower Crane?

A self-erector is a tower crane that is designed to be easily and rapidly transported and erected without the assistance of a large hydraulic crane.

A range of models with varying capacities exist. In the hierarchy of cranes, their capacities are below those of larger “city” tower cranes and are viable for residential and commercial projects six stories and under.

A self erecting tower crane “folds up” upon itself — generally in four or more sections — when being readied for transport.

The tower typically folds into two sections and the jib, depending on its length, will fold into two or more sections. When folded up, the crane’s size is such that it is ready and legal for transport, either on its own mounted highway axles or via flatbed transport.

From the time crane erection begins until the crane is fully unfolded is typically between fifteen and thirty minutes.

Calibration and testing must be done once the crane is erected and prior to use, but the overall duration from the time erection begins until the crane can be in use is a matter of hours — typically two to three.

Smaller self-erectors hold and are transported with their full requirement of ballast, or counterweight permanently attached. Most, beyond the smallest, have additional ballast that is transported and set in place separately. Cranes that have their full requirement of ballast permanently attached are referred to as “self-contained”.

Self erecting crane specifications

Self erecting Crane Features

• operable on tight-boundaries job sites and impassable job sites where other material handlers (like all-terrain forklifts or telehandlers) cannot perform
• excellent reach (from 80 feet and up, depending on model)
• minimal erection and set-up time
• effective material lifting capacity (tip loads from 1,000 pounds and up, and maximum loads from 2,000 pounds and up, depending on crane model)
• useful clearance (hook heights from 55 feet and up, depending on crane model)
• minimal Jobsite “footprint” — between a 10-foot x 10-foot footprint and 14-foot x 14 foot, depending on crane model
• quiet operation (they run on electricity)
• operates on 480v three-phase electricity
• stationary once erected
• environmentally friendly
• easy to operate, with a short learning curve
• radio remote control
• minimal maintenance
• virtually no downtime
• safe operating techniques
• very affordable to rent, and operate
• high-value retention and long useful life

Construction crane

Self erecting Crane Benefits:

The ultimate benefit of self erecting crane usage is, quite simply, value — savings (in construction costs resulting from using the crane) that outweigh the cost (to rent and operate the crane).

Crane users generally report a reduction in manual labor hours equivalent to four or more persons. They also report shortened job completion times — primarily during the framing cycle — of 15% or more, and reduced need for multiple pieces of material handling equipment. And these cranes are much less impactful to the environment as well.

The benefits that drive these results to follow, and are accomplished by the crane features and uses described previously.

Self erecting crane hire

Self Erecting Crane: Improved Efficiency and Productivity.

• for crews that rely on their carpenters to perform the requisite manual labor to get their jobs done, a crane can remove much of the manual labor performed by carpenters freeing them up to focus on what you pay them to do — carpentry; the result is an improvement in productivity that also improves carpenters’ morale and leaves them much fresher at the end of a long day
• use of dedicated staging areas results in a more efficient assembly of construction components (wall sections, roof sections, built-up beams, etc.); materials required in the staging area can be placed in the staging area when needed, and, since navigation of other material handling equipment (like telehandlers) is not necessary, the staging areas do not continually have to be moved or
  disturbed to allow passable access for that equipment
• crane does not require a dedicated operator; rigging and operating can be done by a single person and, with the use of the remote control, the operator can move with the load, reducing the need for someone to “guide” the operator
• the single-person operation for many tasks that otherwise would
  require multiple people (lifting and setting trusses, lifting and
  setting rafters, etc.)
• the minimal footprint of crane leaves much more room on Jobsite for
  material storage, staging areas, etc.
• materials do not need to be handled or moved multiple times to make way for mobile equipment; material can be initially delivered to a “receiving” location and then dispersed a single time to the location of need when needed — the right material, the right quantity, when needed, delivered once

Tower crane uses

Self erecting Crane Uses:

Self erecting crane has many users on the Jobsite. These cranes represent a new and different way to handle Jobsite material handling and hoisting tasks. Therefore, you will find new and different uses for these cranes beyond your customary techniques. In fact, our customers come up with new uses for these cranes on nearly a daily basis. Here is a sample of uses:

• placing Jobsite material (lumber, engineered floor joists, trusses, masonry, etc.)
• raising complete wall sections (first level, lower level, upper levels, interior, exterior, etc.)
• hoisting, positioning, and setting trusses and/or roof rafters
• after you assign dedicated staging/assembly areas, the crane can be used to place materials into those areas, and then remove and position assemblies in place; assemblies include exterior wall sections, interior wall sections, roof sections, gables, dormers, built-up wood, and microlaminated LVL beam sections, etc.
• setting of steel beams, wood, and micro-laminated LVL beams, & interior structural and decorative timbers
• picking up trash receptacles and dumping them directly into your Jobsite dumpster
• placement of roof sheeting
• placement of roofing shingle bundles
• positioning workers, via a “man basket”, to set windows, install siding, install exterior trim, paint, install and/or clean gutters, clean windows, etc.
• access hard-to-reach areas to place or work on assemblies like chimney tops, cupolas, high eaves, gutters, etc.
• placement of concrete via a concrete skip

This is just a sampling of these cranes’ uses. You will continually innovate and find new uses that improve job site efficiency and safety.

Self erecting tower crane for sale

“Once erected, these machines take up a very small footprint, much less than a mobile crane”, “They cover a large area of a project from one location, and don’t require an expensive concrete foundation.”

But first, it’s important to break down the mechanics of a self-erecting tower crane.

“Self-erecting tower cranes swing from the bottom, hence they are bottom slewing tower cranes”. “They are also set up on outriggers, so instead of using a concrete foundation, they are set up much like a mobile crane does, and you can adjust the height of the outriggers to get the crane perfectly level.

Another big difference is that there is no counter jib. So with these cranes, the jibs are held up by the suspension going up the rear of the tower instead of a large counter jib sticking out the back.”

These cranes also typically use wireless remote controls, or wired remote controls, depending on the model. But one of the most impressive attributes of a self-erecting tower crane is it folds up into the size of a semi-trailer, making it easy to transport going down the road.

Self-erecting tower cranes are safer and more cost-effective when compared to other crane and material handling options.

Self erecting tower crane rental

Estimated that the machine population in the U.S. is sitting between 500 and 600, compared to 15,000 self-erecting tower cranes in Germany alone. But while self-erecting tower cranes are not as heavily utilized in North America as they are in Europe, the market is improving as more users see their advantages on the Jobsite. With significant cost savings to customers, a self-erecting tower crane provides a strong return on investment.

Ranging from smaller units (approximately 80-foot radius) to extra-large (around 160-foot radius), the versatility of self-erectors plays a huge role in their benefits. Small models often have self-contained counterweights, and axle sets are possible with the smaller range, making fast erection and onsite moves possible. Small self-erectors are ideal for two- to three-story apartments with multiple buildings.

Mini self erecting tower crane

Small self-erecting tower cranes are easy to train operators to erect and dismantle, and in most cases are cheaper and safer than a boom truck. Estimated that a two-month-long project costs around $55,000 with a boom truck, while an 85-foot self-erecting tower crane with a full-time operator costs only $25,000, with 75 percent of this cost going to the operator. The crane only ends up costing as little as $30 per hour over this period of time.

Counterweight jib crane

A medium-sized self-erecting tower crane comes with counterweights and the axle set, but it is not permanently attached to the axle set. Medium-sized units can be erected in just two hours with three men and two semi-trucks. They have a radius of up to about 130 feet. These machines are ideal for three- to six-story wood-framed structures. They can be moved on the Jobsite in three to four hours. For this size range, Hadland provided the example of a self-erecting tower crane in comparison to a forklift.

Tower crane cost

Self Erecting Crane : Decreased Equipment and Labour Costs

• a single self erecting crane eliminates the need for multiple pieces of material handling equipment like mobile cranes, telehandlers or all-terrain forklifts, boom trucks, etc.
• reduced fuel costs to operate material handling equipment
• can be used on job sites with tight boundaries or impassable terrain where the only real material handling option typically is manual labor
• a crane is a “model employee”:
  • it is on-time to work
  • it doesn’t talk back
  • it is reliable and dependable
  • it never gets tired
  • it won’t ever file a workers’ comp claim
• for crews that employ dedicated laborers, the many cranes use (trash removal, material handling, and lifting, etc.) reduce much of the need for laborers
• the ability to place materials and assemblies anywhere on the Jobsite, including inside the structure (and not just at the perimeter, a limitation of telehandlers for instance), reduces the need for manual labor to perform that task
• quick, easy setup
• jobsite safety is improved due to the decreased need for manual tasks, also drastically reducing workers’ comp claims

• Environmental Benefits
  • operate on electricity from a generator
  • does not leave deep ruts or disturb surrounding terrain as a result of machinery navigating the job site.

Self erecting Crane manufacturers

Tower crane manufacturers – Self Erecting Crane manufacturers:

• Liebherr self-erecting tower crane
• Terex self-erecting tower cranes
• Potain self-erecting crane
• Manitowoc tower cranes

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What is a tower crane? – Tower cranes are widely used for lifting operations in the construction industry. Tower cranes are a common fixture at any major construction site. They are pretty hard to miss… they often rise hundreds of feet into the air and can reach out just as far. The construction crew uses the tower crane to lift steel, concrete, large tools – like acetylene torches and generators, and a wide variety of other building materials.

What are tower cranes used for?

The operating characteristics of a tower crane are largely determined by its type of mounting, type of tower and type of jib.

Static tower crane

A tower crane with a static base only occupies a limited area but is able to cover, from its fixed position, all points at which loads are to be handled within the maximum slewing radius. They can be set at varying heights up to their maximum free-standing height. They can also be extended beyond this limit by tying the crane back to the supporting structure.

Rail mounted tower crane

Rail-mounted tower cranes have a larger area of coverage as they can travel along their tracks carrying their rated loads. However, the height requirement should not exceed the free-standing height as recommended by the manufacturer.

On the other hand, the crane service would be disrupted whenever work must be done on or near the track. The advantage of mobile tower cranes lies in great inward reach without the long jib which would normally be required to reach over the top of the structure.

Self erecting crane

Generally, truck-mounted tower cranes are completely self-contained and can be driven along roads. They are generally capable of comparatively rapid erection and dismantling. They are however generally unable to travel in their fully erected state and cannot handle loads while traveling.

Crawling tower crane

Crawler-mounted tower cranes are required to be transported on a low-loader or towed on special road axles when traveling on public roads. Inside the workplace, some can travel over a firm, flat, level ground carrying loads up to a specified proportion of their rated loads.

They are also able to travel in a partially erected state but without load over unprepared ground provided it is within certain limits of level and compaction.

Tower crane jib

A horizontal trolley jib usually has a smaller minimum operating radius than the equivalent luffing jib and is thus able to handle loads closer to the tower of the crane. For a given height of the tower, however, a greater height of lift is available with a luffing jib, and the jib can be raised or lowered to clear obstacles. One advantage of a fixed luff jib is that its extra height at the jib head enables it to clear objects that would obstruct a horizontal trolley jib. The advantage of a rear-pivoted luffing jib is that it has a smaller minimum hook radius than an ordinary luffing jib.

Articulated jib crane

For articulated jibs, some designs are not required to weather vane. In this case, the crane is made to withstand storm winds with the jib drawn into minimum radius; there is then no need for a 360° obstruction-free slewing path. One type of this crane has a hinged jib arranged so that the outer portion remains horizontal. As the jib is folded, the outer portion rises, giving increased height and the ability to pass over obstructions.

What type of crane do I need?

The selection of a crane for any job should be made only after a thorough examination of all the factors involved. In general, it is good practice to select a machine that has a working margin in respect of the load capacity and other anticipated requirements.

The crane should have a permanent durable plate bearing the manufacturer’s name, machine model, serial number, year of manufacture and weight of the unit for identification purposes.

Every major structural, electrical and mechanical component of the machine should have a permanent durable plate or a clear indication bearing the manufacturers’ name, machine model number, serial number, year of an original sale by the manufacturer and weight of the unit.

Besides, identification numbers should be clearly marked on all basic removable components and attachments of the machine (such as counterweights, etc.) to show that they belong to that machine. It is important that these components should be used only on that machine or identical models or equipment for which they were specifically intended by the manufacturer.

What is a tower crane?

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Radio remote controls are now standard equipment on most self-erecting tower cranes and are even becoming common in some parts of Europe for a flat-top tower crane.

Almost all self-erecting tower cranes come with remote control. A growing number of top-slewing tower cranes use them as well.

“In Europe, remote controls are used only with small top-slewing tower cranes, up to 100tm or 120tm,” The limiting factor, he says, is that operators of larger cranes need to feel the crane reacting to the load so they do not operate too roughly.

Tower Crane remote controls

With digital readouts wedged in between the controls, remote controls have started to look more and more like the load-moment indicator inside the cabin of a mobile crane. They tell users how much the load weighs, and what percentage of the maximum it is, how high the load is, and even how strong the wind is blowing.

What is remarkable is how quickly this has happened. Tower cranes have moved from simple electric machines to computer-control in about 20 years- perhaps half the development time of mobile cranes.

Remote controls have played a key role in this development. Early on, crane owners realized that small cranes are not busy all the time, and so operators who use remote controls can help out with rigging and other site jobs during downtime. Although of course, it costs more, adding a remote control could save an entire salary.

Tower crane joystick

“Sometimes nothing is happening, and then it is possible for the driver to do other things. If you have a remote control, you can walk beside the load. If you have to put a load down softly, you can stand beside the load, and see everything very well.”

These early remote controls would have only replicated the main levers of the crane. Remote controls were an aftermarket business.

Remote controls have evolved away from being a specialty thing

“Twenty years ago, a crane operated by remote without a cable was some kind of magic. Now it is becoming standard for all crane applications, especially tower cranes, and loader cranes and mobile crushers.”

Hetronic remote control

A key milestone was the manufacturers’ decision to start to work directly with remote control vendors in the development of the crane. In 2000, Potain teamed up with German remote control manufacturer Hetronic, according to Potain global product manager.

About the same time, Liebherr’s Biberach tower crane factory also started working closely with HBC-Radiomatic.

The decision was taken with the Igo range in 2000, that because of the evolution in the market toward radio remote controls, we should offer it as standard. It was then a gradual process to roll out standard remote controls.

“This was not about cost; the market was pulling for a solution, and we thought we should follow.”

This move was important because it integrated the remote control into the technical architecture of the crane. Since the manufacturers were buying one unit for every crane, remote control manufacturers could expect much larger orders. By moving from an aftermarket addition to an OEM business, radio remote controls reached the mainstream.

RC Tower crane

PLC remote control

The other feature of this new arrangement was technical cooperation. When OEMs started to work together with radio remote design engineers, remotes became many higher-performance products.

The trend in the industry is for radio remotes to move from being simply transmitter-receivers to going toward the receiver having the features of a PLC, referring to a programmable logic controller (a computer). Receivers need to become more intelligent, and programmable.

“It is necessary to have a long-term partner,” Frech at Liebherr says. “You have to give many things to the partner so that they can provide control signals to the PLC, and give them the possibility to log into our control system. You don’t give someone you don’t know such access.”

A remote control unit based on a computer is also more efficient to manufacture. Instead of having to make 50 different circuit boards for different customers, Hetronic can, for argument’s sake, make five, and adapt each one of those 10 different ways using its H-Link configuration software. The H-Link software can assign buttons to outputs, and program speed increases or decreases, for example.

The next generation of remotes will be even more programmable.

Remote controlled tower crane

Remote control construction crane

The stage looks set to make tower cranes more computer-controlled in the future. “If you look at the market generally, there wasn’t a computer network on the crane; there wasn’t CAN-Bus architecture.”

In the old days, if an operator was unsure of the weight of a load, he would try to raise it on the crane. If the crane’s limit switches to cut out the hoisting motion, then he would know that it was too heavy to lift. Now, control software available in the Potain Igo T and MCT ranges will interpret the crane’s load chart and warn the operator before the limit switches to cut out.

This same software will help crane operators determine how far they can trolley out a given load on the hook.

Now, on the latest cranes, there is, and optional extras such as site signaling lamps or zone limits can be slotted in without detailed set-up, extra programming, or complex troubleshooting.

“That is pretty recent, and I have not seen that elsewhere on self-erectors.” Tooled-up end-users or dealers will configure the crane using an input screen inside the electrical cabinet of the crane itself.

Describes the interface as similar to a mobile phone’s menu-type system.

Potain tower crane

The Hetronic control for the Potain T85 displays trolley radius, hook height, weight, percentage capacity remaining, battery power, signal strength, wind speed, whether the crane is in two-fall or four-fall configuration, and warnings at 90% and 100% of crane capacity.

The first models displayed one piece of information; now screens display all of it.

Remotes with data feedback have become something more than just levers connected to the crane by a wireless radio link. Now a computer- or several computers – sit between the levers and the crane motors. The software that interprets the signals that display the information also moderate the crane operator’s actions.

“What is most interesting in tower cranes now is the control system,” “A tower crane is a steel construction, but there are more and more control and monitoring systems.”

Tower crane design

The main objective of the project is to design robust, fast, and practical controllers for tower cranes to transfer loads from point to point in a short time as fast as possible and at the same time, keep the load swing small during the transfer process and completely eliminate it at the load destination.

Moreover, variations of the system parameters, such as the load weight are taken into account.

A tower crane is one of the major items of equipment used in the construction of high-rise buildings. However, crane operators do not receive adequate information, such as the target space conditions and the material being lifted, to control the crane. This limitation degrades productivity and safety. This study describes a prototype of a tower crane equipped with wireless control (IR remote control) technology.

With these advanced technologies, the tower crane can provide the crane operator with an enhanced view of the workspace and various other functions providing up-to-date material status. The tower crane can also provide faster information flow with greater accuracy and improved driving efficiency.

The tower crane was used to test its performance. The main objective of the project is to design robust, fast, and practical controllers for tower cranes to transfer loads from point to point in a short time as fast as possible and at the same time, keep the load swing small during the transfer process and completely eliminate it at the load destination.

Moreover, variations of the system parameters, such as the load weight are taken into account. The results confirmed considerable improvement in operational speed and significantly enhanced performance in workplace safety and communication efficiency.

Remote Control Tower Crane

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