Going to Extra Lengths!

Enlarge Image Image 1: Tadano's TR-600XXL-4 RT crane features a new longer boom.

December 17, 2004--The rough-terrain crane market has been nothing but brutal for the past 10 to 15 years. At the peak in the early 1980s, North America bought upwards of 2,000 units per year, but at one point that number dropped to about 200 annually. While nobody is standing on the roof tops hailing the return of the “good ole days,” there is some sense of optimism for 2004 sales, predicted to approach about 600 units.

 
The biggest sellers are units rated at 60 metric tons and larger, and Tadano's latest addition targets this expanding 60-ton market. The TR-600XXL-4, however, isn't really a new face, but an old friend with a little more stick.

The TR-600XXL-4 (Tadano Rough-Terrain, 60 metric tons Extra Extra Length, 4^th Series) is essentially the highly successful 600XL-4 with one more boom section. This five-section, full-power boom features a tip height of 226 feet, a 47-foot increase over the old model. Although developed to target applications where reach is more important than capacity, it is interesting to note that there was little if any sacrifice made in many of the more critical load charts. There are a lot of features that differentiate this Tadano RT crane from competitive units, but none more interesting that its Automatic Movement Limiter (AML).

 

 

Flexibility and control

Enlarge Image Image 2: Tadano's AML is much more than a load moment indicator

The AML is Tadano's own internally developed load moment indicator which monitors boom elevation, cylinder pressure, boom angle, boom length, and the extended length of each individual outrigger. This works to inform the operator through a conventional, yet large, LCD display located in the cab. For the crew working nearby, a colored light system provides an external safety-warning feature.

Enlarge Image Image 3: Flashing lamps provide visual status reports to support crews.

Orange lamp flashes when any boom function moves the crane into 95% to 99% of capacity. Red lamp illuminate the crane is at 100% of allowed capacity. An audible alarm is used in conjunction with the lights. As the AML system detects boom movement the controls are also monitored, automatically cutting out hazardous positioning when the crane is operating at 100% capacity. Sudden stops are eliminated with an automatic ramping, or soft stop, feature.

 

Enlarge Image Image 4: Shown here is one example of how the exclusive, non-symmetrical multi-position outriggers can be set.

A key feature that sets Tadano's AML apart from other load indicating systems is its ability to facilitate Tadano's exclusive non-symmetrical multi-position outrigger system. Unlike many systems that limit outrigger positions to essentially three positions, the TR-600XXL-4's outriggers can be set individually in one of four pre-set positions. Dozens of outrigger configurations are possible. Sensors detect outrigger positions, the degree of rotation of the superstructure, and the boom's elevation and extension. The AML then works in conjunction with the soft stop system to allow the crane to be used appropriately in a wider variety of confined applications.

 

Another exceptional feature of the AML is its lift recorder which monitors and documents the previous 50 lifts. At the same time it logs the top ten overloads, detailing the complete crane configuration, date, and time. This information can be accessed directly from the on-board system without the need for any peripherals.

 

The following is a summary of the AML's nine functions:

 

• Moment ratio or main hydraulic/torque converter pressure
• Boom angle or moment percentage
• Boom length or potential hook height
• Load radius or swing angle
• Actual load read out
• Rated lifting capacities
• Jib offset angle or number of parts of line
• Boom position indicator
• Outrigger state indicator

 

In addition, a working range preset function is provided for load radius, boom angle, tip height, and swing range with automatic speed reduction and soft stop function on the boom elevation and swing functions.

 

Next issue, I will give you a nuts-and-bolts review of the crane, including my final verdict. Meanwhile, delivery of the first units began earlier this month to Scott Construction Equipment in Monroe, La. Serving the petro-chemical market, Scott Construction Equipment told me they were thrilled with the extra reach the TR-600XXL-4 provides.