Above: The straddle carrier lifts a monopole base section, which can weigh up to 70,000 pounds.
A material handling solution for awkward and oversized loads
July 2013 - With the flip of a switch a home is filled with light, a stereo coos soft jazz and a frozen meal becomes dinner. Then, with a zip, it all goes black. Americans typically undervalue electricity until it stops working. According to the U.S. Energy Information Administration, electricity use in 2011 was more than
13 times greater than it was in 1950. Consumers depend on reliable electricity, and as demand grows, additional transmission lines are needed.
The Susquehanna-Roseland Electric Reliability Project is intended to improve service for millions of people in the Northeast with its 145-mile, 500,000-volt transmission line from the Berwick area in Pennsylvania to Roseland, N.J. Atlanta-based industrial distributor HD Supply is the contracted material management company for part of the project, which uses steel monopoles. Originally, the company planned to use cranes to transport the structures but found a better solution with a straddle carrier from Combilift, Monaghan, Ireland.
“The monopoles come in four sections, and each section can weigh anywhere from a few thousand pounds, upwards of 70,000 pounds,” says Kevin Eckrote, operations manager of HD Supply Power Solutions. “We utilize the straddle carrier to load and unload any of those structures that weigh over 30,000 pounds.” Eckrote says the decision was a no-brainer because the straddle carrier costs less than a crane, operators do not require crane certification and lifts are much safer.
A balancing act
The straddle carrier was first developed in 2008 and officially launched in Ireland in April 2010. HD Supply’s Pennsylvania location received its machine in January 2013.
“Initially the straddle was designed with the container market in mind as a low-cost alternative to big reach stackers or forklifts to handle the same load,” says Gearoid Hogan, VP marketing at Combilift. “There are other handling systems out there for moving containers, but our machine is cheaper to maintain, service and run, and still handles up to 20 loads per hour depending on the application.”
After some use in the market, Combilift discovered the straddle carrier could handle any oversized product. “Very quickly we realized there were other applications such as oil tanks, cable reels, structural steel, modular home units, mobile power generators, etc. Our machine isn’t just a container handler,” says Hogan.
The company manufactures a standard straddle to lift containers from ground to trailer and a telescopic double stacker, which can telescope up and down for double stacking and low doorway entrance. Fully automatic top lift attachments can be added, depending on the number of containers to be handled. The height or width of each machine can be customized to lift any size product up to 180,000 pounds.
The straddle carrier’s lift mechanism works by using hydraulic cylinders connected to wire ropes. “You drive over your product, lower your lift points or attachment, attach to the load, then you hydraulically lift it up,” says Hogan. “That allows you then to travel around your yard, load trailers or go through a low doorway with the product.” The front two points are synchronized and operate with one hydraulic lever in the machine while a separate lever operates the rear lift points. “We also have a standard front and rear independent side shift for easy placing of a load or a container onto a trailer,” he says.
The standard straddle carrier features three wheels for maximum stability without the need to add suspension. “We use a hydrostatic drive system to propel our machine and maintenance-free dynamic braking system to stop the machine. So it’s one less wearable item for a company to worry about,” says Hogan. “We also offer three-wheel drive options for use in rough ground conditions.”
Out of harm’s way
Anyone lifting a load wants to maintain a consistent load rating all around, meaning weight must be evenly distributed without any large concentration in one area. When the straddle carrier is fully loaded, there’s more area to distribute the weight than there would be with a regular forklift. Once the product is engaged, it can be lifted above the operator’s cabin, stabilized and locked in. “We lift the load 6 feet off the ground; this gives the driver 360-degree visibility from our centrally located, ground-accessible cabin,” says Hogan. “This also allows easier access to the engine compartment for service.”
Eckrote cites safety as the key benefit of the straddle carrier. “It allows for a much safer lift than using a crane,” he says. When unloading, the straddle carrier drives over the trailer while the monopole still is secured to the trailer. Workers place two slings around the structure before releasing any of the tie downs that hold it to the trailer. “Since the structure is always secured, it completely eliminates the risk of the pole falling or rolling while we’re moving it from the truck to the ground or from the ground to the truck,” says Eckrote.
“We utilize one operator and one spotter. In a crane operation you could have multiple spotters and an operator. It reduces the use of manpower and it’s always secure,” he continues. “We don’t have a situation where that pole, which could weigh 66,000 pounds, is not free on the trailer; it’s not dangling from the air on a crane.”
Saving time and money
Eckrote says the cost of the straddle carrier is three times less than the cost of a crane. “And we keep realizing the savings because it uses less manpower than a full crane operation,” he says, adding a crane requires a wide area for setup and use. “The straddle carrier operates in its own footprint, so you only need as much room as the straddle carrier to move around.”
Hogan also notes transporting a crane from inside a production facility to the outside requires placement on a trailer then offloading with a forklift. “Your straddle carrier could act as your crane inside the building to load the product, drive it outside and load it on a trailer. It could do the job of a crane, a transfer trailer and a forklift,” he says. Also, when offloading a trailer, the straddle carrier can lift the container off the trailer, the trailer could leave the premises and the container could be destuffed on ground level. The speed of this action lowers trailer rental prices for customers.
The telescopic straddle carrier can store containers up to three high. “Companies save their storing profit in their yard. They can store three high, but then they can collapse it when they need to get in and out of building,” says Hogan.
Combilift’s willingness to customize the machine to HD Supply’s specific monopole work was essential. A specially made stock bracket prevents the machine from lifting and holds the pole securely in place. Raising the bracket the wheels mount to by three inches gave HD Supply clearance to use tire chains in the winter months.
“Customization has been part of Combilift’s goal,” says Hogan. “A container’s a container. That has consistency, but when it comes to individual products, like cable reels, tanks and structural products, there’s going to be differences in what parts need to be picked up, what length, height and width area. Part of our goal has been the ability to customize for customers so it’s not just cookie cutter. It’s very much a consultative process.”
It all begins with conversation and a customer site survey. Combilift has a team of engineers, as well as a team that works on customizing trucks, asking questions and getting clarification.
“We gave our Combilift rep drawings of the actual poles we’d be lifting and then what our concerns would be and then they came back with the stop brackets for lifting the poles up so they wouldn’t swing or sway,” says Eckrote. “They also looked at the layout of the yard and were able to give us some examples of how we were going to store and warehouse the materials and how the straddle carrier would benefit us storage-wise.”
Beyond customization of the machine, Combilift sends a technician to oversee assembly and conduct operator familiarization on-site. “Initially, Combilift provided hands-on training, as well as documentation to certify our operators that were already power-equipment certified through HD,” says Eckrote. HD Supply operators also were authorized as trainers, so any future staff could be trained by its own personnel. “It’s been a great partnership with Combilift,” he says. “It’s a great venture and I think we’ll be able to utilize this equipment quite a bit in the future.” MM