Specifying Backhoes For Maximum Versatility

Back To The Basics
By Don Talend, Contributing Editor | November 2009 Vol. 64 No. 11
Manufacturers now provide an increasing selection of backhoe attachments that give handling capabilities like grappling.

Starting points
The contractor should first select a backhoe by dig depth class and price range and by various features, options, specifications and attachments that are appropriate for most projects, Bargellini says. Other important items are productivity, fuel efficiency, safety, serviceability, operator comfort and dealer service support, he adds. Paul Grohsmeyer, backhoe loader marketing manager for Caterpillar Inc., notes that adding an extendable stick to the rear boom can expand the digging depth by up to four feet. Another variable affecting the digging depth is the bucket size, Grohsmeyer adds.

One of the most important specifications is backhoe bucket breakout, or digging, force, according to Bargellini. This is the maximum calculated force in pounds applied at the tip of the bucket teeth. Calculations are based on the highest system relief valve setting. Both the bucket digging force and dipper digging force are factors in determining work output. The other factor that determines output, Bargellini says, is speed, which is determined by available hydraulic flow. Lowell Stout, senior product manager, and Reith of Terex Construction America prioritize horsepower, bucket breakout force and stick force because all of these contribute to the machine’s ability to move and lift material, says Stout. Knowledge of typical soil types is valuable in determining the necessary bucket or stick breakout force. Although horsepower affects how quickly the machine can work, the right power to weight ratio is a more accurate predictor of productivity.

In recent years, manufacturers have been developing more powerful and intelligent hydraulics. Bargellini notes that almost all manufacturers now offer optional or standard pilot controls as opposed to mechanical “wobble sticks.” Besides being light to the touch and less tiring for the operator, pilot control joysticks can be converted from backhoe to excavator control with a switch of a lever, usually located inside the cab.

Digging depth and capacity are two items to specify early in the decision process. An issue related to digging depth, and often considered a factor in productivity, is the reach of the rear boom because the greater the machine’s reach, the less often it needs to be repositioned during trenching operations. Bargellini notes that reach from the swing pivot is measured as the distance, at the ground line, from the backhoe swing pin line to the end of the bucket teeth with the backhoe fully extended.