Playing It Where It Lies

Aug. 30, 2011

When a machine breaks down in the field, it’s a given the repair will require a few more steps to complete than if it had failed while parked in the yard. There are innumerable mechanical and environmental variables to any in-field welding repair, and because each repair is unique, no rigid operational policy will fit all situations. One factor, however, is completely under the equipment manager’s control: the human variable.

When a machine breaks down in the field, it’s a given the repair will require a few more steps to complete than if it had failed while parked in the yard. There are innumerable mechanical and environmental variables to any in-field welding repair, and because each repair is unique, no rigid operational policy will fit all situations. One factor, however, is completely under the equipment manager’s control: the human variable.

First, determine how much of the repair is owned. If  the machine is rented or leased, emergency field repair options are described in the contract. It may include doing an equipment swap with the rental house, waiting for the dealer’s service truck, calling an independent welding repair service, or doing the repair in-house under the guidance of a remote service rep. Much of the same holds true for owned equipment if the downed machine is still under warranty or service agreement.

Regardless, when equipment breaks down on-site, the first response for many fleet managers is to do something—anything—to fix it regardless of the service resources put in place when the machine was acquired.

Managers must resist the temptation to work around the service or lease agreements’ parameters in an attempt to quickly return the machine to service. Rogue repair welds may be a small, even hidden, part of the equipment’s fix, but they can carry costly consequences. Dave Landon, manager of welding engineering at Vermeer, cautions that a welding repair done outside the bounds of your contract can void your warranty or service agreement.

“If the equipment goes down again and the service provider has to fix the ‘fixed’ repair, a failure analysis will tell if the proper procedures were followed initially and if they were the cause of subsequent failures,” he says. Supply field supervisors with detailed instructions that explain how field repairs are to be handled.

If it is necessary to perform the weld in-house, contact the manufacturer for up-to-date repair procedures for the machine’s make and series model, Landon says, suggesting a conversation will augment any printed or on-line repair manuals as service references.

“The OEM’s service desk will be able to give information about your model series that has not made it to the online service manual and advise you on procedures and materials that will give you the best weld repair results,” he says. The weld itself may be a small part of the fix, but it could directly affect a machine’s future productivity. Ask for directions.

Whether welding is performed in-house or outsourced, insist on taking adequate time to identify the failure and plan the repair. “If you don’t know what you’re looking for, you don’t know what you’re looking at,” Landon says.

“The telltale mark of a welder who thinks he’s good enough to work without a plan is the one who has sheet metal ripped off, parts and pieces scattered around the site, and is running back and forth to the truck,” says Dean Black, a welding instructor at the Apprenticeship and Skill Improvement Program of the International Union of Operating Engineers Local 150 training center in Wilmington, Ill. “The welder who is at the truck quietly reading the manufacturer’s specs and assessing the equipment’s mechanical, electrical and hydraulic fundamentals is building his work plan.”

Before the repair beings, the welder should know how the machine is to be used when the repair is finished.

“A skilled certified welder can do a repair in different ways according to what the owner wants,” says Mark Otto, another ASIP welding instructor. “Let him know if you are looking for a quick weld repair to keep the machine on the job just one more day, on that project for several more weeks, or want a temporary solution until you can get the equipment into a shop.” Understanding the expected end result is the starting point in his repair plan.

Field welding repair usually uses the shielded metal arc welding (SMAW or stick welding) process and flux-cored arc welding (FCAW or flux-cored) process. John Liesener, product manager with Miller Electric, says stick welding is still the most common process worldwide in construction because it is portable and requires less equipment. Set up is simple because stick doesn’t require hoses, wire feeds and regulators, so the service truck carries less weight.

“Stick welding has the field advantage for steel repairs because stick doesn’t require gas tanks, which can be a consideration on some construction sites,” Liesener says.  

Stick electrodes are more portable than wire rolls and come in a variety of filler metals, such as sticks with nickel for cast iron welding, he says. A service truck stocked with a selection of electrodes gives the welder flexibility to work on more of the machine’s parts.