Rubber Tyred Gantry Cranes for Container Terminals

RTG, the rubber tyred cranes are mobile cranes employed for lifting, moving and for staking the standard containers in stacking terminals in the specified staking areas. These cranes serve to stake many rows of containers in these container yards for rail or road, for achieving the maximum sorage density because of limited space in container terminals

Normally, a container loading crane moves on rails rather than rubber tyres. A RTG and a straddle carrrier are almost similar in appearance when viewed from the side. RTG has a moveable crane on its top. RTG, rubber tyred gantry cranes are especially used equipemt at the container yards for handling the normal 20 and 40 feet containers. These cranes are used almost all over the world at different largest container terminals for performing this specific job of handling the millions of containers annually. RTGs serve in most econoimical manner for straddiling of multi lane containers at rail or a road yard to get the maximum sorage density.

One example of well designed and successfully used RTG cranes is Konecranes which has been innovated very intelligently by its designers. The machine employs the components which have proven their performance and require the least amount of maintenance with utmost dependability. These cranes provide the performance consistent to the customers’ expectations.

Konecranes RTG cranes have many additional features over and above the standard specifications of these gantry cranes. These additioanl features add to the performance substantially and help to considerably reduce the maintenance costs and down time of this equipemtn

The additional features are as follows:

1. The crane has its exclusively designed sway prevention system that prevents the sway of spreader rather than only dampening the sway.
2. The spreader has a horizontal fine positioning that enables to move it 300 mm without movement of trolley in the direction of trolley movement.
3. Spreader trim along with its hoist mechanisam eliminates the need of an additional trim mechanism.
4. This gantry crane has sixteen wheels and reduces the cost of civil works in container yards by causing minimum damages in the area of operation.
5. Gantry drive is direct and there is no chain or wheels with sprokets. This feature imparts smooth movement to gantry and even the maintancne is lowest.
6. It does not have any hydraulic mechanism for even wheel steering or for micromotion of antisway spreader. These RTG machine mostly work in marine environment, they perform most reliably owing to this feature with least maintenance cost.

Construction and use of traveling gantry cranes

Gantry cranes are the most commonly used for lifting, raising, lowering down and shifting of heavy loads in industry or shipyards from different locations. The gantry cranes have steel fabricated structures in their main parts.

Construction of travelling gantry cranes:

Gantry cranes lift a load with the help of a hoist. The hoist is fixed to a movable trolley, which moves horizontally on rails fitted to a beam on the wheels under it. The crane has uprights supports and can move on the wheels. These cranes are more suitable for handling heavy loads. Huge gantry cranes are used in various industries like shipbuilding or for moving heavy loads in other industries. The gantry crane with tires or caster wheels is used in many industries. These movable gantry cranes are named workstation gantry cranes used for moving the materials, parts, and products between different workstations. These cranes may have I-beam, tracks or other extruded metal sections in their mechanism for lifting of loads. Many cranes do not move when lifting the loads. They move only in unloaded condition. The load capacity of a gantry crane is dependent on design and structure of the cranes.

Use of travelling gantry cranes:

Very common use of the travelling gantry cranes are there in rail yards, shipping docks and industries for loading, unloading and movement containers and of loads. In industry, they are employed for moving the items from floor to floor for production and assembly operations of products. In production and assembly operations, the material, parts, sub assemblies, or assemblies need to be frequently moved from one workstation to another. The loads are so heavy that it is impossible to handle them manually without the aid of material handling equipment. The gantry cranes help in the mobility efficiently. Final products are much heavier than the parts and require lifting and transferring them with the help of gantry cranes.

Parts of a mobile gantry crane.

Let us discuss about the various parts of a gantry crane. Two steel structured vertical columns support a horizontal beam at its ends. The beam carries a moveable lifting hanging mechanism called a spreader on it. The lifting mechanism can travel along the horizontal beam. The lifting mechanism is employed for lifting the load. The gantry cranes are mounted on four wheels at the corners for movement of crane. Two wheels are used for steering the crane while other two are driven by motor for movement over the floor. These wheels may be lined with rubber on the rim. The operator can move the crane to proper position, lift and raise the load and move the load to another location. It is difficult to control the movement of load due to swing resulting from the crane mechanism. It becomes more difficult, if the floor is filled with many machines and items and crane cannot move easily because of the obstructions to move it.

How useful are small gantry cranes

Gantry cranes are overhead cranes with a bridge and a trolley attached to a hoist. The load is lifted with the overhead hoist connected to the crossbeam. Crossbeam is mounted on rails or on wheels. In small gantry cranes, wheels are more preferred. After lifting the load, it is possible to move the load from one station to another in a factory or shipping yard.

The load can be moved along the rails or wheels as well as across the crossbeam. The gantry cranes are produced in many sizes- one small for normal use in a warehouse and to that huge size used in a dock to load ships. In industry, for example, a typical use can be lifting an automobile engine with a gantry crane. More powerful and larger cranes are used in many other industries for handling variety of products and materials.

Two largest gantry cranes are located in Belfast in Northern Ireland in a dry dock. These mark the history of largest cranes named Goliath manufactured in 1969. Samson had erected it in 1974. These exemplify the power and versatility of gantry cranes.

In fact, gantry cranes are smaller than Samson and Goliath cranes. Most of these cranes are portable cranes, which are not mounted on rails. In industry, mostly cost effective medium or small gantry cranes are used. The uprights are fixed on polyurethane caster wheels for maximum maneuverability and the cranes can handle up to 5-ton load easily.

Gorbal is a good quality portable gantry crane traded by Ergonomic Partners. It is provided with bolted attachment between uprights and cross beams for maximum safety. The Gorbal cranes are either operated with an electric or manually operated hoist. Other manufacturers also build similar cranes that can be operated either way. If you need to lift heavy loads less frequently or lift heavy loads more frequently at different locations, portable gantry cranes are more useful for their inherent flexibility for use.

Portable small gantry cranes:

Generally, portable gantry cranes are built with a load capacity between 1 and 5 tons and crossbeam span of 30 feet. The design may vary with end use and some of the cranes may not need a full runway. ASCE rail can be successfully use on portable gantry cranes. ASCE rail is just like steel rail and it can be installed on floor for moving the crane. In case the crone is to be frequently used at various places within the industry, a portable gantry crane without tracks is ideal alternative. The crane can move on tires or on caster wheel that are lockable.

Portable gantry cranes are more safe and cost effective compared to forklift trucks. They are more powerful and versatile. Gorbal is the pioneer for manufacturing of portable gantry cranes renowned for their strength, durability, and safety. Gorbal has facilities to manufacture small portable cranes in Alabama and Network, USA. There is option to buy the cranes with fixed or adjustable widths and heights as guaranteed reliable products guaranteed for five years.

Types and Advantages of Steel Portable Gantry Cranes

Advantages of Steel Portable Gantry Cranes:

You may need a variety of equipment with different load capacities and range for lifting and handling different heavy loads and materials for different jobs in your factory. It will require a battery of steel portable gantry cranes readily available inside the factory or warehouse so that your trained staff can carry out the work efficiently in minimum time with the most suitable equipment.

You have several benefits from steel portable gantry cranes rather than using only fixed type expensive cranes. The portable cranes are suitable for almost all sizes of the business and can be very useful for hauling the material, if you are searching for a right solution. The fixed type of lifting equipment is able to move the material from one location to another easily. It has high initial cost and there are a number of restrictions to its use. It cannot serve you beyond a particular area in its range. For other locations you need steel portable gantry cranes.

However, there is limit of the load lifting capacity for a portable crane is lower than fixed cranes. Nevertheless, these cranes can be utilized to move the materials any one location to another location successfully. The workers will feel that it is the most convenient solution for them in most of the material lifting and movement within the workstations.

Types of steel portable gantry cranes:

You can get several types of portable gantry cranes. The cranes are designed to work in normal working surroundings. The major task involves the lifting of materials and heavy components from floor level to different workbenches and back. These cranes are designed to operate in the minimum possible area and at the same time, they should reach the normal workbenches. The base size of crane is 68 inches and can easily work in most of the small units.

For every user the important factors are the weight lifting capacity and the range to operate in a particular environment most economically to meet his requirements. There are many models and some of them are most commonly used. Lightest steel gantry crane weighs 228 lbs and can lift almost same amount of load i.e. 300 lbs due to its lightweight structure. This crane is most suitable for small workshops. You should invest in a stronger crane to lift heavier loads, if you can accommodate that in your workshop. You may be surprised to know that the most powerful portable gantry crane weighs only 300 lbs while it can lift a load of 2000 pounds. The crane can be easily handled and can lift a wide range of loads making it most convenient for the people to get to it and use immediately.

Safety is the most crucial factor in using any type of crane. The golden rule is that “never lift a load beyond the capacity of a crane and follow safety instructions” to avoid any accident.

Different Types of Gantry Mounted Cranes

Gantry mounted cranes are most useful for handling of containers in container yards. A rail mounted gantry crane is moves on the rails to lift and stack the 20 and 40 feet containers with the help of a spreader or a twin lift spreader. The cranes are available in diverse models with different size of overhangs and spans. The gantry-mounted cranes are expressively designed for specific stacking and handling containers in docks as well as other container yards.

RMG cranes have additional benefits as compared RTG cranes. These are powerful driven with electricity, higher haulage capacity clean operation, and higher speed to travel with load. The RMG cranes are most productive for the shipment of containers by road and rail and transfer heavy loads. These applications of the crane require speedy movement in both longitudinally and crossways. Moreover, these cranes have additional feature of automatic self-positioning for their efficient performance.

Examples of gantry mounted cranes:

Terex stacking cranes can handle exhaustive container stacking at local as well as international docks and other points with maximum productivity. Terex RMG cranes boast to haul containers and swap bodies on container terminals for stacking and railways.

Features of RMG:

The main features of gantry-mounted cranes are:

• Anti-sway system
• Approved weighing system incorporated with crane
• System for crane management and data transfer
• A piggyback

Examples of other gantry mounted cranes:

Another type of RMG crane is LPMC whi9ch is especially designed for container yards. It works on electric power available in yard and can lift, move and stack containers using 20 and 40 feet telescopic types of spreaders or with the help of twin-lift spreaders.

Features of LPMC gantry mounted cranes:

LPMC is specially meant for the container handling in yards and is most productive in comparison to RTG crane that is mounted on tires. LPMC is powered with electricity to lift heavier loads at higher speeds. It comprises different mechanisms for lifting, trolley transferring, gantry, and dampening sway. These mechanisms mostly operate with the help of a control system that works on Ac frequency conversion. These machines work smoothly usually employing a single drum for lifting operation. Double drum types of cranes are also used. There are a couple of options available for these cranes and the user can select them according to his requirements: Trolley slewing mechanism permits slewing between -10 and +190. You can use continuous slewing also. Overhauling beam RMG gantry crane can reach beyond rail travel. The other choices are RMG for different rail gauge, with generator power and twin-direction anti-sway mechanism. The quayside container crane, portal cranes, ship loaders, and RTG are the different gantry mounted cranes.

Overhead Industrial Cranes

Overhead industrial cranes are among the most versatile and cost effective mechanisms that can be installed in a factory or other facility. Such cranes can help an organization maximize the use of its space, speed up production and reduce costs.

The main advantage to overhead industrial cranes is obvious: they provide a transportation system and a lifting mechanism that doesn’t put any more machinery on the floor. This can obviously save space which can be used to add workers and machinery to the floor. It can give workers more room to do their jobs and even increase safety.

Get Vehicles off the Floor

A big benefit of overhead industrial cranes is that they get vehicles like forklifts off the floor. This can make the workplace safer because vehicles won’t be driving around the floor. Obviously moving vehicles on the floor can lead to accidents which can cause injuries or damage to machinery.

Moving vehicles on the floor can also interfere with work. Workers may have to interrupt what they are doing to move out of the way as a vehicle passes. A worker could also have to stop his work to go and get a vehicle to move something or lift something.

An overhead crane enables workers to lift loads and move loads around the work area without vehicles. This lowers the possibility of accidents and the amount of interruptions to the work.

Increase Efficiency

A system of traveling overhead cranes such as a materials handling system can smoothly move loads around the facility. This could enable workers to stay in one place and do their job rather than move around as loads move.

Overhead industrial cranes can be used to bring supplies and equipment right to workers on the floor. This can reduce the amount of time spent away from the work area fetching supplies or equipment. It can also limit the amount of equipment and items on the floor freeing up space for work.

There are other ways that overhead industrial cranes can increase efficiency. Such cranes can be used to load trucks or trains from overhead which is faster than using a forklift. They can also be used to move bulk loads very quickly and to pick up large items on the shop.

Installing Overhead Industrial Cranes

The variety of overhead industrial cranes available today is incredible. There are dozens of kinds of overhead cranes with all manner of capabilities. This means that a company could have a very hard time deciding which crane to buy and install.

The best way to evaluate overhead crane needs is to hire a professional crane company. Professional crane companies have staffs of experts including crane technicians and crane engineers that can evaluate your needs and tell you which crane you should purchase.

Such companies can even design, build and install custom cranes and crane systems for very specific needs. Overhead cranes can eliminate the need for workers to handle potentially hazardous or dangerous materials such chemicals. Overhead cranes can even be used in clean rooms and other environments where people can’t go.

There are now overhead industrial cranes to meet virtually every need. A professional crane company should be able to help a company find the crane or crane system that will meet its needs.

Hand Signals for Overhead Bridge Cranes

There are quite a few hand singles for overhead bridge cranes. These signals are used for both safety and day to day work purposes.
It is vital that a workplace that uses an overhead bridge crane develop and adopt a uniform set of hand signals for overhead bridge cranes. These signals let the overhead bridge crane operator know what is going which ensures safety in the workplace. Such signals enable workers to communicate effectively and safely with the bridge crane operator.
If an effective set of hand signals for overhead bridge cranes is not adopted and implemented. Workers and the bridge crane operator may not be able to understand each other. This can lead to some very tragic consequences including accidents, injuries and even deaths.

The Signaler

The best way to ensure safety is to have only one person in the work area make signals to the operator at once. There should only be one signaler in the work area to prevent mixed signals and confusion.
Having one signaler enables the crane operator to know who to pay attention to and who to ignore. It also ensures that only individuals who know what they are doing will be sending signals to the overhead crane operator. One way to make sure that the crane operator knows who the signaler is to have the signaler always wear a specific piece of clothing such as an orange vest.
Signalers should also be as familiar with the operation of the crane as possible. The best way to ensure familiarity with the crane is to have the signaler operate the crane. Having the signaler and the crane operator trade places occasionally will make sure that both the signaler and the crane operator are familiar with each other’s jobs.
Designating a few signalers who are familiar with crane operation and hand signals for overhead cranes is the first step in crane safety. The next step is to never allow anybody but the signalers to signal the crane.

Hand Signals for Overhead Cranes

The hand signals for overhead cranes are pretty simple and very basic. Generally pointing a finger up indicates that they want to move something up. Pointing down means that the workers want something lowered. Two raised fingers will usually indicate a need for multiple crane trolleys.
Other common signals include pointing the thumb up for bridge travel and making the hitchhiker’s signal for trolley travel. A flat outstretched arm usually indicates stop. Moving a flat outstretched arm back and forth usually indicates emergency stop. Holding hands together on the front of the chest indicates that an operator should “dog” everything while both arms outstretched means the magnet is disconnected or turned off.
Even though hand signals for overhead cranes can be a very effective means of communication they do have their limits. It is always a very good idea to have another means of direct communication between an overhead crane operator and the workers on the floor available. Radio telephones and walky talkies are ideal for this purpose. Headsets that workers can put under their helmets and wear at all times will make communication even easier.