As we all know,Crawler Cranes are important tools in construction,milling and other heavy industrial projects.They usually have huge body and heavy weight.Because of the super heavy body, the crawler crane can’t move on public roads like a trunk-mounted cranes.So, do you know how to transport a crawler crane?
Moving crawler cranes is a big challenge.When a job finished,we need to transport crawler cranes from one site to another before the next begins.This is a more complex process than we imagine.
There are two core methods of removing the crawler crane.
1 Disassembly and transport by trailer
In summary,this method is disassemble crawler crane into multiple parts.And send them to the destination by trailer separately.It includes following steps.
Step 1:Preparation works
Meticulous planning and complex road permit are necessary.Measure the height/width restrictions and bearing capacity of roads along the way.Ensuring trailers can pass the roads without damaging them.
Destination or departure place both need to prepare a solid and flat place for disassembling and assembling the crawler crane.
Step 2: Disassemble crawler crane
When preparation works are ready,the disassembly process could begin.
Huge Boom sections are divided into multiple parts for convenient transport by flat trailer.
Counterweights are removed from crawler crane as individual parts.
Finally,completing the split of upper carriage and undercarriage,the disassembly process is finished.
Pay attention,the overall process must follow prescribed order and rules avoiding crawler crane pouring down.
Step 3:Loading and transportation
Crawler crane’s loading needs specialized trailers.
As the heaviest part of crawler crane,upper carriage needs to be transported by Multi-axle platform trailers with extremely heavy loads.It needs to be firmly fixed on trailers by steel rope and triangular wooden wedge frame.
Remaining parts include boom sections,counterweight and track plates will be transported by different types of trailers according to their features.
Step 4:Arriving and assembly
Once all the parts arrived,the assembly could begin.The assembly sequence is exact reverse of the disassembly sequence.When finish the assembly,please inspect crawler crane again ensuring the security of crawler crane.
2 Disassembly-free method SPMT
SPMT is an innovative method created an alternative choice for giant crawler cranes.If the crawler crane’s load weight over 4000 tons or needs fast transportation,this method is tailor-made.It can save disassembly and assembly time but need high technology support.
It adopts a smart flat transport vehicles named SPMT with dozens even hundreds wheels.The vehicles can be remote controlled by computers.Multiple SPMT vehicle groups come to the under of crawler crane,lifting up at the same time.It includes the following steps.
Step1:Strictly condition confirmed
Before starting the transportation of crawler crane,there are some conditions must be confirmed to ensure the personnel and equipment’s safety.
1 Delivery distance should be extremely short.
Although the technology is already feasible,due to the giant weight,the crane just could remove an extremely short distance,usually under 1-2kilometers.
2 Remove on excellent path
The path should be flat,solid and without steep slopes.Strictly prohibited Walk on soft dirt roads, roads with hidden manholes, pipe trenches, or unknown underground facilities.
Step 2:Maximum loss weight
This is the most crucial step.As it improves safety and reduces wear and damage to the ground caused by the crawler crane.
1 Remove all counterweights
Remove all the counterweights from the rear of the vehicle and the frame.
2 Shorten or remove the crane boom
Typically, only the bottom one or two sections of the boom are retained.Sometimes the boom is even completely removed.The remaining boom should be kept at the minimum elevation angle, or even placed horizontally to reduce instability during transportation.
3 Remove all accessories
Remove all non-essential accessories such as the boom, hook, wire rope winch (if removable), and sunshade outside the cab.
After the above series of operations, the weight of a crawler crane can be reduced by 30%-50%.Meaning that the weight of a 400-ton crane can be reduced to less than 150 tons when it is self-propelled.
Step 3 Extremely slow movement speed
To reduce the inertia caused by rapid movement,crawler crane needs to keep a extremely slow movement speed,usually controlled at 5-10 meters per minute.The crawler crane is typically used in the micro-motion mode or the micro-speed travel mode.
Avoid sudden stops and starts during the transfer.The route should be kept as straight as possible, with fewer turns. If a turn is necessary, it should be done by turning slowly in place.Keeping one track stationary while the other turns slowly.
The entire process requires sounding horns as a warning to signal unauthorized personnel to stay away from the scene.
Step 4 High-frequency security checks
The following items are typically checked by stopping every 15 minutes or every 100 meters.
|
Inspection part |
Specific content |
|
Walking mechanism |
Check the crawler crane undercarriage for abnormal overheating, unusual noises, and oil leaks. |
|
Crane track shoes |
Check the track shoes for cracks or deformation, check the pins connecting the tracks for looseness, and remove any stones stuck in the track gaps. |
|
Lubrication status |
Check and replenish the lubricating oil in critical components such as shaft pins and bearings. |
|
Ground conditions |
Check the path for indentations and cracks. |
|
Overall status |
Check the overall structure for looseness and the electrical wiring harness for any pulling. |