Types of Electric Overhead Travel Cranes ( EOT Cranes )
Crane has been used as an important part of a working landscape since its invention. They are usually used in heavy lifting tasks and construction. There are different types of cranes available for different requirements. Each type of crane is crafted to meet the particular requirements of users. In this write-up, we will be seeing various types of EOT (Electric Overhead Travel) cranes that are available at the best EOT Cranes Manufacturer in Ahmedabad.
EOT Crane Full Form (Electric Overhead Travel)
There are various types of overhead cranes, industrial cranes & EOT Crane pdf with many being highly specialised, but the great majority of installations into one of three categories.
- Top running single girder bridge cranes,
- Top running double girder bridge cranes and
- Under-running single girder bridge cranes. Electric Overhead Traveling
What are the different types of cranes?
EOT Cranes
EOT Crane stands for Electric Overhead travelling cranes. This is the most commonly preferred EOT crane that is usually used in load lifting and shifting. They have the parallel runways and the gap is spanned by a travelling bridge. The hoist is mounted on this bridge. These cranes can be operated electrically.
Single girder cranes
The crane consists of a single bridge girder supported on two end trucks. It has a trolley hoist mechanism that runs on the bottom flange of the bridge girder.
Single Girder Cranes are the ones that are used in work units where heavy materials required either shifting or lifting. These cranes are solely used for maintenance and manufacturing purpose. The primary purpose of these cranes is to move heavy materials quickly and conveniently. These cranes offer high durability and can perform very well.
Double Girder Cranes
These are the cranes that have a capacity of 2 to 50 MT. Double Girder cranes can be used all heavy lifting purposes. The hook of these cranes can be lifted up to greater heights when compared to the single girder cranes. These cranes can be used in both interiors and exteriors. This is one of the added advantages of this type of cranes.
Jib Cranes
The Jib Cranes are a budget-friendly option and they will serve you in various ways. These robust cranes are capable of lifting heavy weights with ease. They have a broader reach and can cater to different kind of requirements.
Girder Bridge Cranes
The crane consists of two bridge girders supported on two end trucks. The trolley runs on rails on the top of the bridge girders.
Hot Crane
The hot cranes are ideally designed to use in factories where lifting and shifting of heavy material are carried on. They are not used in construction sites. These cranes are used to handle metal manufacturing process. From refining to dispatching the metal, these hot cranes takes care of the entire work.
Gantry Cranes
The Gantry cranes have a flexible and dynamic design with staunch moving ability. They can be used to carry heavy weighted goods from one place to another with the utmost convenience.
These cranes are essentially the same as the regular overhead cranes except that the bridge for carrying the trolley or trolleys is rigidly supported on two or more legs running on fixed rails or another runway. These “legs” eliminate the supporting runway and column system and connect to end trucks which run on a rail either embedded in or laid on top of, the floor.
Monorail
For some applications such as production assembly line or service line, only a trolley hoist is required. The hoisting mechanism is similar to a single girder crane with a difference that the crane doesn’t have a movable bridge and the hoisting trolley runs on a fixed girder. Monorail beams are usually I-beams (tapered beam flanges).
What is the meaning of EOT Crane?
The Electric Overhead Travelling cranes are the most frequently used cranes in the construction places and in industries. These cranes are operated with the help of electricity and one can operate it either by control room attached to the crane or by a pendant. These cranes have the capacity to lift both heavy and lightweight goods.
Single Girder EOT Cranes Means
The single girder EOT cranes are lighter when compared to the double girder ones and they have only one main bridge. They are mostly used for short period work and they help in lifting light duty loads to be precise one can lift 1 to 20 ton of load with the help of single girder EOT cranes. They are manufactured in both top running and under running models.
Double Girder EOT Cranes Means
Double Girder EOT cranes are used to lift heavy weights. They are a cost-effective option when compared with single girder cranes and are capable of lifting heavier weights. They are compatible with wide pans. They have two main bridges and this makes it robust as well as sturdy in nature.
How does EOT crane work?
The EOT crane works by using electricity and it can be operated with the help of either the driver or the pendant (remote control). The crane is capable of lifting up to 500 tonnes with a span of 60 meters. The universal coupling mechanism is incorporated in these cranes to facilitate both installation and adjustment. The mechanism consists of only four active and driven wheels, if the weight that has to be lifted is more, the wheel pressure is reduced. The articulated frame device will distribute among the four wheels so that the weight doesn’t pressurize only a particular wheel.
Which Crane should you choose – Single Girder or Double Girder
A common misconception is that double girder cranes are more durable! Per the industry standards (CMMA/DIN/FEM), both single and double girder cranes are equally rigid, strong and durable. This is because single girder cranes use much stronger girders than double girder cranes. The difference between single and double girder cranes is an effective lifting height. Generally, double girder cranes provide better lifting height. Single girder cranes cost less in many ways, only one cross girder is required, a trolley is simpler, installation is quicker and runway beams cost less due to the lighter crane dead weight. The building costs are also lower.
However, not every crane can be a single girder crane. Generally, if the crane is more than 15 ton or the span is more than 30m, a double girder crane is a better solution. The advantages and limitations of Single / double girder cranes are as follows:
Single Girder Cranes Works
- Single girder bridge cranes generally have a maximum span between 20 and 50 feet with a maximum lift of 15-50 feet.
- They can handle 1-15 tonnes with bridge speeds approaching a maximum of 200 feet per minute (fpm), trolley speeds of approximately 100 fpm, and hoist speeds ranging from 10-60 fpm
- They are candidates for light to moderate service and are cost effective for use as a standby(infrequently used) crane.
- Single girder cranes reduce the total crane cost on crane components, runway structure andbuilding.
Double Girder Cranes Works
- Double girder cranes are faster, with maximum bridge speeds, trolley speeds and hoist speeds approaching 350 fpm, 150 fpm, and 60 fpm, respectively.
- They are useful cranes for a variety of usage levels ranging from infrequent, intermittent use to continuous severe service. They can lift up to 100 tons.
- These can be utilized at any capacity where extremely high hook lift is required because the hook can be pulled up between the girders.
- They are also highly suitable where the crane needs to be fitted with walkways, crane lights, cabs, magnet cable reels or other special equipment.
EOT CRANE CONFIGURATION
- Under Running (U/R)
- Top Running (T/R)
EOT Crane Working Principle
There are three working movements of EOT Crane- crane hook up and down lifting, trolley lateral movement and crane long travelling longitudinal motion.
The motor exhibits a driving force of the hoisting mechanism. This transmits the power to high-speed shaft end. The ring gear transmits the driving force and then with the help of pulleys and wire ropes the crane hook is driven up and down. Similarly, the half gear coupling, its joint and compensation shaft will help in rotating trolley wheels.
Under running cranes
Under Running or underslung cranes are distinguished by the fact that they are supported from the roof structure and run on the bottom flange of runway girders. Under running, cranes are typically available in standard capacities up to 10 tons (special configurations up to 25 tons and over 90 ft. spans). Underhung cranes offer excellent side approaches, close headroom and can be supported on runways hung from existing building members if adequate.
The Under Running Crane offers the following advantages:
- Very small trolley approach dimensions meaning maximum utilization of the building width and height.
- The possibility of using the existing ceiling girder for securing the crane track.
Following are some limitations to Under Running Cranes
- Hook Height – Due to Location of the runway beams, Hook Height is reduced
- Roof Load – The load being applied to the roof is greater than that of a top running crane
Lower Flange Loading of runway beams require careful sizing otherwise, you can peel the flanges off the beam.
Types of EOT cranes catalog
There are various models of EOT cranes available in the market. If you want to know more about these types of cranes, their specifications and decide which one among them is your right choice, just download the catalog. It has everything you want to know about EOT cranes.
Double Girder EOT Crane Catalog
Single Girder EOT Crane Catalog
