Duty Cycle and Electrical Crane Equipment

TDC standard draw works has a life expectancy of more than 200,000 hrs before overhaul. Typical draw works consists of a heavy bedframe with lagged drum, alloy shaft, alloy bull gear, alloy pinion, parallel shaft reducer and electric motor. The input shaft of the reducer is extended on the outboard side with a mounting face to accept the brake. The following photos show our 2,000 hp, draw works. Each winch weighs more than 70,000 lbs. We use the same basic configuration of components on 2- rope and 4-rope machines. Our standard size range is 20,000 lbs to 200,000 lbs line pull. We have the strongest winches in the industry.

We refer to the portion of the machine below the rotating bed as the carbody. The carbody must support the entire weight of the crane, provide a roll path for the crane to rotate on and provide the bull gear for engaging the slew drives. In a duty cycle machine, you cannot afford to have problems with the carbody. Our carbody and roll path design is simple, rugged, repairable, durable and has a lot of redundancy built in.

With balanced deck configuration, the center of gravity is designed to be no more than half way from the kingping to the front rollers under full load at maximum radius and not more than half way from the kinpin to the rear rollers with no load and minimum radius. This ensures good distribution of loads onto the roll path with outstanding stability in all situations. Hook arms are provided to prevent uplift however these are not relied on for load carrying.

Deck rollers are forged alloy, 4140 heat treated and deep hardened. Rail is heavy cross section, capable of withstanding high forces repeatedly. We cut our rail ends on a 45 degree bias to provide a smooth transition for the wheels to pass from one rail section to the next.

Our kingpin is 4140 heat treated alloy steel, supported by a heavy weldment bolted to the carbody. Center pin spherical bushing is lubricated by the autolube system.

TDC slew bull gear is 25ft pitch diameter, built in segments to allow replacement or re-location without undecking. Gear is alloy work hardening steel with dp 1.25, 20 degree pressure angle and 8 inch face width. You are never at risk of being out of business with a broken gear segment. Any segment can be repaired, replaced or re-located to position on the roll path that is lightly used. Long life, repairability and survivability are essential.

TDC duty cycle booms are built with a wide base and heavy lattice construction. On dredge crane booms, we typically use mild steel angle bar chords with square tube lacings to provide a boom that is torsionally strong and can handle heavy side loading and shock loads. Stevedoring machines up to 50t use mild steel square HSS chords with square lacings and are lighter than dredge booms.

TDC booms have heavy cross-brace diaphragms closely spaced to provide torsional rigidity and plate construction in areas of high stress. Our luffing attachment and head sheave geometry is designed to slightly "hog" the main boom structure.

In the worst-case load combinations, we keep the stresses below 15,000 psi in the chords and the slenderness ratio below 30.

TDC booms are the strongest in the industry. You can drive 2 semi-trailer trucks side by side inside the boom shown below.

TDC Operator Cabin is constructed of 1/4" thick steel plate with angle bar stiffeners, rock wool insulation, perforated steel cladding, in-floor heating, climate control A/C, thermal glass, and a watertight door. Steel is coated with epoxy mastic, stripe coat with epoxy mastic, and finally, one coat of polyurethane. This provides a robust, corrosion-resistant marine duty cab that is comfortable and quiet with excellent visibility and good protection from direct sun through the windows.

Controls

All functions are controlled by the left and right joysticks with 4 buttons and one trigger on each joystick.

Left Joystick

1. left joystick 12:00 pay, 6:00 haul boom hoist

2. left joystick 3:00 slew right, 9:00 slew left

3. left joystick button 1 tagline haul

4. left joystick button 2 tagline brake

5. left joystick button 3 slew brake

6. left joystick button 4 horn

Right Joystick

1. right joystick 12:00 pay holding, 6:00 haul holding

2. right joystick 3:00 pay closing, 9:00 haul closing

3. right joystick button 1 winch lock

4. right joystick button 2 auto-open

5. right joystick button 3 auto-close

6. right joystick button 4 horn

TDC cranes are easy to operate without a level of skill. There are no foot pedals and no frictions; everything operates from 2 joysticks with programmable buttons. You will never be held for ransom by the need for elite operators.

Acceleration, speed, and drive characteristics are programmable via a control pad on the drive. There are no PLCs.

For dredge cranes, we build selectable spud controls to allow the crane operator to manage shifting.