Two ConocoPhillips megaloads made their way from an overnight parking spot along Highway 3 to the refinery in Billings.
The Emmert International trucks hauling two halves of a coke drum started moving shortly after midnight and arrived at the refinery after 3 a.m. Billings police and Montana Highway Patrol officers escorted the shipment through town.
Work crews moved street lights, utility lines and signs out of the way of the wide and tall loads as they moved down Airport Road, onto Main Street in the Heights and into downtown Billings.
The trucks' route took them westbound on Montana Avenue before making a tight turn onto 27th Street and then Minnesota Avenue to the refinery.
Dozens of onlookers lined streets to get a look at the slow-moving procession. Police reported no incidents during the morning effort.
A police escort will help a gigantic load finish its journey to the ConocoPhillips refinery early Wednesday.
The coke drum, split into two pieces, was slated to move between midnight and 6 a.m. Wednesday from atop the Rims through downtown and to the refinery at 401 S. 23rd St.
The 80-person crew that is hauling the massive refinery equipment into Billings anticipates some tight turns downtown, Police Officer Mark Keyes said.
"The tightest turn they will have to make is the one off Montana and 27th Street," Keyes said. "There are lights at that intersection, and there is a railroad signal there, too, on the tracks."
As the load sat atop the Rimrocks, crews spent Tuesday preparing for the last part of the journey by moving hanging street lights and signs along the route.
Keyes said a lieutenant and four officers, along with four Montana Highway Patrol troopers, would block off streets as Emmert International, the heavy-haul transportation company, moves the 300-ton megaload through town early Wednesday.
"We block off the streets as we roll," Keyes said. "They aren't closed — closed where you can't get through — but they are closed as we go."
The slowest part of the journey likely will be at intersections with 90-degree turns. The megaload is scheduled to make three such turns at the corner of Sixth Avenue and 15th Street, 15th Street and Montana Avenue and Montana Avenue and 27th Street. The turns were expected to take at least 45 minutes.
Crews work in front of the load to remove traffic lights, overhanging signs and pull up power lines. Another crew follows to put everything back after the drum goes past.
"They figure that this will be the most difficult part of the journey, weaving through the city here," Keyes said.
The drum left Lewiston, Idaho, on Feb. 1 after several weather delays.
The load is permitted to travel only at night between midnight and 6 a.m. traveling at top speeds of 35 mph. Height limitations prevented the transportation team of about 80 people from taking the interstates.
"These are the biggest pieces of equipment in the refinery," refinery manager Steve Steach said. "There's a 15-foot height limit, and they had to be made in one piece. Sideways they are 24 feet high."
Steach said they looked at four or five routes before the transportation process started in February. He said the route they took was the only one without height restrictions.
The drums were built by a company in Japan. Originally in one piece, they were split in half, to be welded together when they arrive.
Steach said the drums will be welded together in August.
The coke drums are part of the coker, which uses heat and pressure to convert heavier components of crude oil into a lighter and cleaner products including gasoline, diesel and jet fuel.
Steach said the drums operate at 900 degrees. The two original drums were installed in the early 1990s. This is the first time the company had to replace the drums.
"They have been in service for 20 years, and that's about their life span," Steach said. "With them heating up and cooling down every day, it fatigues the metal."
It will take several days just for the load to be lifted off the trucks. After that, the moving crew will head back to Lewiston to bring the second drum, which is also split into two pieces.
"We are confident we can do an even better job next time," Steach said. "We have a couple lawsuits out there that we are not involved in and we don't think they are going to affect our permits. We improved upon the plan all the way along."
The next megaload is scheduled to leave Idaho around April 25 and arrive in Billings in June.
The plan was to have them installed this spring. Because of weather delays, the drums won't be installed until next year.
In the meantime, the company is on a short shutdown while the original drums are being repaired. The refinery will be closed for up to a month while the new coke drums are replaced next year.
Another piece of large equipment must be brought in to complete the installation — a 400-foot-tall crane that will be brought to Billings in pieces by 250 semitrailers, Steach said.
"The crane has to be able to lift it up and out," Steach said. "It's really a engineering marvel to replace it."