Frequently Asked Questions
TOP > Frequently Asked Questions
- What are the merits/demerits concerning electromagnetic disc brakes used on the traveling motor of gantry cranes and what are recommended updated braking system?
The electromagnetic brake is chosen because of its low cost for container crane gantry motors. Let’s examine both merits and demerits as follow:
* Less initial cost
* Good outward appearance
* Maintenance of brake lining wear is tough
* Visible inspection of the brake pads is not possible
* Adjustment of brake torque is not practical. Because the small distance adjustment and the many numbers bolts needed to be adjusted.
Recommended brake for traveling motion of gantry cranes.
“M-mountable” and “N-mountable” <Link to IB30V Disc Brake _M_mountable and N_mountable >
- What are the Features of the I-flex Coupling?
The I-flex disc coupling requires no lubrication, thus eliminated the risk of contamination by leaking lubricant contaminating the disc resulting in a reduction of the braking torque. In addition, the replacement of the I-flex brake disc is possible without the need of removing the motor or the gear drive unit.
On the contrary, in order to lower cost, it is common to use a gear coupling with disc brake installed between the electric motor and the reduction box, yes cheaper but many negative aspects result. The main disadvantages are as follows:
* visible maintenance confirmation is not possible
* the need to add regular lubrication which leads to leaking of oil
* spraying of excess oil which contaminates the disc and brake
* Area becomes dirty with oil and grease
As a better solution, the I-flex Coupling which offers the following positive merits:
* Parts are visible for easy maintenance
* No need for lubrication- oil/grease
* Bushings and bolts are easily replaceable
* The brake and surrounding area stays clean and oil free
- Is asbestos used in the pad material?
No. The friction material of the pad that we have developed is a composite material using powder metallurgy technology called ‘ Sinter Metals’, totally asbestos free.
- What is Icans track record of retrofitting from drum shoe brakes to disc brakes?
Up until the early 1990’s drum shoe brakes were the predominant type of brake used in a wide variety of industry. As in the automotive industry, the introduction of simpler and extremely effect disc brakes has led to a shift to retrofitting and the installation of disc brakes in the crane industry as well.
Ican was extremely active in retrofitting hundreds of older drum shoe brakes starting in the mid-1990’s. In addition, All second hand cranes exported by Ican have been upgraded with much more safer and modern disc brakes. Currently the world trend is continuing towards the safer, easier to maintain and performance efficient stopping power of the industry standard disc brakes.Drum brake lining replacements are very time consuming and basically a complicated task involving running-in of the lining surface to attain acceptable requires labor, time and readjustment.
Along with the replacement of the brake, there are much better alternatives to the gear coupling that are still widely in use today. Such an option is the development of a flexible coupling to avoid the need for lubrication maintenance thus, to avoid creating a greasy, dirty operating environment. The I-FLEX coupling developed by Ican has been successfully in operation in both cranes and industrial applications receiving very positive reviews.
- How to relocate a large container crane to overseas?
In order to reduce cost and time of relocation work, the crane is loaded on a heavy lifter in its original shape without diassembling and transfered by sea. On the other hand, the use of heavy floating cranes for loading and unloading at both ports envolves more cost and time for cargo handlying. Hence, Ican utilizes the roll-on/roll-off system where special care and attention is paid to the ships condition, the wharf height, sea level, and the weather. In addition, the forces acting on the crane cargo at sea due to the weather along the navigation route are fully researched and the lashing strenght is carefully determind by extensive computer analysis. To date, Ican has logged over 50 successful accident free crane relocations.
- How to strengthen crane runaway accident prevention?
The Recent increase of Quay Crane Runaway Accidents worldwide caused by strong winds pushing the cranes out of control as a result of recent increase of violent weather such as tornados, typhoons and sudden wind gusts, have been on the increase. The conventional method used is the stopped clamp system or the rail clamp but is effective only when the crane is stationary. But the rail clamps are useless when the crane is in motion. Crane operators experience many dangerous near-misses due to the sudden surge in movement caused by sudden gusts of wind. Cranes using outdated drum brakes are at the mercy of the wind when being moved. A total lack of safe control.
Operators have the right to dependable emergency brakes to insure safe response to adverse conditions. Ican has developed both the IRB-N and/or the IRB-P brakes as an effective combination with Ican’s IB30 disc brake to dramatically increase the safety margin.
Refer to News Release > “Ican Report No.12” and “Ican Report No. 14”.
- What is the difference between positive (active) brakes and the negative brakes?
Positive brakes are actuated by an external force. Negative brakes are actuated by the force of a spring and are released by an external force.
Example: Automobile brakes are positive brakes, actuated by applying foot pressure to a hydraulic piston which presses the brakes. Springs release the brake force.
Negative brakes work in reverse like elevator safety brakes are always closed and the braking force is applied by a spring. Hydraulic or electromagnetic pistons are used to to release the spring force thus releasing the brake.
- What is the difference between drum shoe brakes and disc brakes?
Drum brake is operated by pressing brake shoe to drum which is turning with shaft. Braking power is not stable as heat radiation is not good in comparison with disc brake. Drum brake was installed in cranes in the past. However they are going to be replaced by disc brakes. Particularly replacement to disc brake of cranes in overseas port is progressing as maintenance is easy in addition to the good performance.
Disc brake operates by cramping metal disc turning with shaft. Heat radiation is good as the surface of disc contacts the air to cool down except for the part contacting bake lining. Also performance is stable as generation of alloy powder is small. You can leave out the trial operation to adjust contacting space as brake lining contacts the disc with parallel. Replacement of brake lining is quite easy and reliability will increase by adopting automatic lining wear adjuster etc.
- What is the difference between service brake and held (emergency) brake?
The role of brake is different.
Service brake works to brake the machine in the every day operation. Friction brake will equip automatic friction controller to adjust controlling power as brake lining will be worn. Electric brake works without notable wear.