E-Crane delivers solution for loading sand and gravel
Shamrock Materials provides ready-mix concrete and a diverse line of concrete accessories and building materials, as well as masonry, stone products and landscaping materials from six California locations. The company has been in business since 1954.
In 2005 Shamrock built a transloading facility at Petaluma to unload sand and gravel to be used for production of concrete. These materials arrive by ship from Canada and are transferred to barges at anchorage in San Francisco Bay. After staging, barges are taken one at a time up the Petaluma River, a tidal waterway that joins the San Pablo Bay to the north end of the San Francisco Bay. The barges must reach the Shamrock facility on the high tide and be unloaded well before low tide, which is about six hours later.
Robert McIntosh was the President of Shamrock’s Landing Way Depot for this start-up project and ran the operations for several years. He is now an independent consultant with his own business, but still has close contacts with Shamrock.
Searching for the right machine
“We started with a self-unloading barge,” McIntosh said “but that was a slow, inefficient, low capacity operation. We needed something much better for full scale operations.
“Next we considered a 700-hp diesel excavator that could unload about 650 tons per hour. That was still too slow, reach was marginal, and we anticipated high maintenance and downtime due to wear and tear on the complex hydraulic arrangement. We expected we would have to replace the excavator every 10,000 to 15,000 hours. That cost plus the risks and likely interruptions to our operations were unacceptable. Further, the clamshell bucket was very awkward to use and required lots of operator training. So we continued our search.”
McIntosh explained that during the investigation process, Shamrock became aware of E-Crane’s uncomplicated equilibrium design with its high capacity, simple maintenance, long service life and ease of operation – all the things the Shamrock transloading operation absolutely needed. E-Crane people came to Petaluma to explain how the E-Crane works and learn about the Shamrock operation.
“We explained our situation,” McIntosh said, “and they came back with a comprehensive proposal that made it very clear, very quickly that the E-Crane was perfect for Shamrock’s unloading application. Their approach was very simple and accommodating: ‘Here’s what you need’.”
Shamrock Chief Operating Officer Jeff Nehmens further explained: “This was an entirely new type of operation for us, and we were making long-term decisions about equipment we were unfamiliar with. The E-Crane USA sales team, and Mark Osborne in particular, gave close support to our evaluation and decision process, and it became clear that E-Crane was the only rational choice. That decision and the continued relationship with E-Crane has vindicated our selection, and we would enthusiastically recommend E-Crane to anyone with similar needs.
Reach, lift and cycle times
“The essential machine design is ideal for the controlled-motion ‘lift-and-drop’ cycle we need,” Nehmens said. “The E-Crane configuration and power options enabled us to get the reach, lifting capacity and cycle times we needed, with the fewest possible moving parts. Being able to do that with electric power is a huge advantage, and one we underestimated in the early stages.”
Shamrock utilizes a Series 1500 E-Crane with the optional 300-hp motor (250 hp is standard) and has a 1,200-ton-per-hour capacity. The machine has an 86-foot outreach, 18.2-ton duty cycle capacity, and 20.9-ton lifting capacity.
“The assembly and construction crew was very professional, very knowledgeable – they really knew what they were doing. Everything went smoothly in spite of heavy rains and generally horrible weather. When that first barge was unloaded, we knew we had a winner,” McIntosh enthused. “Smooth, quiet, efficient operation, and the E-Crane can unload faster than the 1,000-tph shore equipment can handle.
“As the E-Crane clamshell bucket closes, there is a corresponding lift so that the jaws close directly against each other and can closely scrape the bottom of the barge,” McIntosh added. “The E-Crane puts a skid loader into the barge toward the end of the unloading process to scoop material into piles, and the clamshell picks up these dregs.”
E-Crane trained Shamrock’s operators and maintenance personnel on site. Nehmens said that the operators took to the machine immediately because of easy operation, cabin comfort and clear visibility. Operators perform a spray-lube on the swivel before each shift, and they check and top-off the auto-lube system as needed. The maintenance group services the bucket lube points daily.
Other than regular inspection and fluid checks, there has been “impressively little” maintenance needed, according to Nehmens. “We’ve been operating the E-Crane 1500 since the end of 2005 with no serious problems of any kind.”
“The operation and maintenance manual is very comprehensive and easy to understand,” McIntosh added. “The E-Crane has a very short learning curve. Standard maintenance involves a fifteen minute routine at start-up for each barge transloading cycle. The automatic lubrication system does almost everything else.”
“We engaged the E-Crane service team to do the early service work on our machine,” Nehmens said. “And we expect to continue with service calls periodically just to have an experienced eye to look for possible wear, to critique our operating and maintenance work, to update training for our maintenance staff, and to offer tips to our operators.”
Shamrock has purchased an additional bucket since the original purchase. The new bucket was hard-faced before going into service, and the original bucket was rebuilt, hard-faced and held in reserve. “We originally intended to buy the new bucket from an aftermarket supplier,” Nehmens said. “But as we experienced the E-Crane equipment in the service environment, we decided to stick with the factory bucket.”
The E-Crane product line includes five series of machines based on capacity requirements: 700, 1000, 1500, 2000 and 3000 models – for scrap handling and offloading or transloading bulk materials from barges and ships, up to Panamax class. Outreach ranges up to 165 feet and duty cycle capacity up to 50 tons. The hydraulically pivoting, mechanically linked boom design keeps the machine in near perfect balance throughout its full working range. Having gravity work for you instead of against you reduces horsepower requirements and power consumption as much as 50 percent.