Though the market for crawler cranes is currently seeing a slow take-off due to delays in project execution, manufacturers are introducing more advanced solutions to meet present and future application requirements across different capacities. NBM&CW takes a look.According to industry observations, demand for crawler cranes is expected to remain skewed towards the 45 T, 80 T, 100T, 150T capacity hydraulic crawler cranes which are being used in expansions of roads and bridges and in the development of metro projects. However, the industry envisages that the middle and higher capacity crawler cranes of 600-750-1000 and 1350 tons will find increasing use in both upcoming greenfield projects and in the expansion of existing refineries, cement plants and nuclear power plants. The duty cycle crawler crane of 100-150 tons with line pull variation is likely to see demand from new marine projects in major ports including jetty expansion and onshore LNG terminals, though demand is likely to be modest owing to the higher price of these specialized cranes.
Says Chandra, “Improvisations are being made in the state of the art LICCON software to enable greater ease of operation and maintenance. To reduce cost of operation, the engine power output is as per the loads to be lifted, which also makes our cranes more fuel-efficient. Improvisations are also being made in the vario tray counterweights and fall protection systems for safety during operation. We are looking at what could be made redundant and ensuring the right marriage between the hydraulics and the engine systems.”
The Derrick of the LR 1300.1 is now equipped with newly designed adjustable suspended counterweights. Liebherr “HS series” duty cycle crawler crane ranges from 40 t to 300 t capacity while the “LR series” manufactured at Liebherr Werk Nenzing ranges from 110 t to 300 t capacity.
For easier planning and greater accuracy during lifting, the new “Crane Planner 2.0” from Liebherr is truly remarkable. Some of the features are the interactive 3D model visualization, all relevant planning data incorporated and used for real time calculations for a given lifting scenario, easy to use tools, instant ground pressure calculation for every crane configuration with load etc.
“The Crane Planner 2.0 is an ideal tool for planning engineers, it helps them to create a virtual job site scenario and plan the lift with the exact boom configuration required for the lift. Thus the “Crane Planner 2.0” enhances the safety and efficiency of the lift on the job site by providing real time calculations including ground pressure” says Mr. Molankar.
Liebherr has recently delivered two units of LR crawler cranes with free fall winches to a major contractor. The crane has a maximum main boom combination of 87.5m and can be configured with a luffing jib and fixed jib as well.
He adds, “ACE has a very strong presence in the crawler crane market, and the company is constantly innovating to enhance the cranes’ load lifting capability. We are using lighter material of higher tensile strength and also increasing the overall height of the cranes. Our crawler cranes can handle heavy loads under stable conditions and do pick and carry jobs in 50% of the rated load capacity. The reduced weight of our crawler cranes has minimized their cost of transportation, and we have developed stronger booms fabricated from high tensile seamless round tubes to keep the weight lower and increase the lifting capability of the cranes. Since the crawler tracks are extendable/retractable, the track can be retracted during transportation and extended when in use.”
Safer & Operator Friendly
Addition of safety features minimizes downtime and is a key step being taken by manufacturers. Improvements are being made in fall protection systems, over swing protection systems, machine inclination sensors, and counterweight detection sensors. Electronic controls like horizontal and vertical load path finders are also bringing more safety and efficiency at job sites.
Sany has incorporated an advanced algorithmic programmable logic controller to enable an interlinked operational safety system. For over swing protection, inclination sensors cut-off the over swing function beyond the permissible limit.
The new machines are equipped with ergonomically designed cabin with self-weight adjusting comfort seats along with 20 degrees tilt and panorama view. The control buttons and joysticks are completely electronic with high precision and self-induced proportional system. Also, the operations can be interchange between any operating handles to make it operator friendly and easier to operate.
Safety features in ACE crawler cranes include safe load indicator with overload cut off function, counterbalance valves, hoisting limiters on main hoist, boom hoist and auxiliary hoist. Boom angle indicator, level sensor, mechanical drum locking system for all the hoists, mechanical swing lock, tri-colour audio visual external safe load indicator, audio slew alarm and safety brakes on hoist are the added features. The operator cabin is ergonomically designed with self-weight adjusting seats, safety belt, and a 20-degree tilt. The control buttons and joysticks are completely electronic with high precision and self-induced proportional system. Also, the operations can be interchanged between any operating handles to make it easier to operate.
Strengthening Product Support
Sany has a centralized warehouse in Pune to channelize spare parts from over 120 dealer locations across India. The company has deputed over 50 dedicated crane service engineers serving through 25 service locations.
ACE has a separate vertical in-house to take care of high value machines like crawler cranes with timely aftersales service and spare parts. It has a robust aftersales service network of dealers and area offices across 100+ locations. About 21 regional offices in key tier-I and tier-II cities are connected with product and zonal heads through the Marketing HQ and a dedicated Product Support Division in Faridabad for enabling a faster response and machine turnaround.