Robogrind brings more precision, safety to tank pit grinding

March 1, 2011
ROBOGRIND OY has arrived in the United States. Developed in Europe as a cost-effective, high-precision system for grinding and polishing the inside walls
A La Porte TX company has become the first in the United States to use Robogrind Oy’s high-tech system for grinding down pits and polishing away stains in tank containers.

ROBOGRIND OY has arrived in the United States. Developed in Europe as a cost-effective, high-precision system for grinding and polishing the inside walls of tank containers, the technology is now available at a Houston, Texas-area tank repair shop.

Custom Tank Innovations LLC in La Porte, Texas, received the first Robogrind franchise in North America, and has one unit now in operation. Management hopes this will be just the first of several computerized grinding and polishing machines in the Custom Tank Innovations shop.

“We believe we are in the right location to offer this service in the United States,” says Jeff Coleman, general manager of Custom Tank innovations. “The Robogrind machines were designed specifically for tank containers, and Houston is the largest intermodal tank container hub in the Western Hemisphere. Tank container activity is driven by the chemical industry, which has a large presence in Houston and across the Gulf Coast.

“With the first Robogrind unit we'll build up our customer based over the next year. Our initial focus will be on tank containers, but we hope to add a second unit in a year or so that can also be used for tank trailers.”

Custom Tank Innovations was created specifically to implement the Robogrind system. The company set up operations in a 3,000-sq-ft shop rented from Tank Service Inc, which is also an investor in the new company. Tank Service sells new and used portable tanks, Cheetah dropframe tank container chassis, and Perolo tank container hardware.

In addition to servicing and repairing tank containers, Custom Tank Innovations offers custom fabrication services. Tank containers are the focus for now, but the work bays are 50 feet deep and can accommodate tank trailers.

Robogrind's robot was first developed in 2002 by a Finnish group, and the technology was sold to a Dutch firm that same year. A lot of redevelopment work went into the initial design--hydraulics and a laser guidance system brought greater precision; a second grinding arm was attached; and a more powerful grinder replaced the initial unit.

“In the end, we had powerful, computerized machine that is capable of achieving plus or minus 10% of the thickness target when grinding down pits or polishing away stains in the inner shell of a tank container,” says Bob de Bos, Robogrind general manager. “We can achieve uniform minimum metal removal of 0.05 mills around the entire circumference of the tank in a single pass. Maximum metal removal is 0.1 mills. The hydraulic driven motors maintain constant pressure during grinding and polishing. Grinding and polishing precision is critical due to the slim tolerances in shell thickness on today's tanks.”

De Bos says benefits of the Robogrind system include job turnaround that is up to 75% faster than traditional grinding and polishing operations. Labor requirements can be cut by as much as 80%. In addition, Robogrind makes grinding and polishing safer, because no workers are inside the tank while operations are underway.

“Following set up, a single operator can run multiple Robogrind units in a repair shop,” de Bos says.

At Custom Tank Innovations, Coleman says he believes it will take about 4½ days to perform a complete grinding and polishing job on a 20-ft tank container, depending on the severity of pitting. “Our initial goal is to process one tank container a week,” he says.

As the economy heats up in the coming months, Coleman is optimistic that there is plenty of potential business in the greater Houston area. Many of the tank containers currently stored at depots across the Gulf Coast region will need refurbishment before being returned to service.

Posing in a tank container with the Robogrind unit are [from left] Jeff Coleman and Craig Aldridge, Custom Tank Innovations LLC, and Bob de Bos, Robogrind Oy.