Dig into Wheel Loader Bucket Selection

A general-purpose bucket is not always the most profitable choice for your earthmover.

Volvo redesigned its rehandling buckets in 2016 to deliver an increase in fuel efficiency due to the faster fill rate and reduced spillage.
Volvo redesigned its rehandling buckets in 2016 to deliver an increase in fuel efficiency due to the faster fill rate and reduced spillage.

Most wheel loaders come equipped with a general-purpose bucket. While these buckets work well in most applications, there may be a more productive and cost-efficient solution that’s better tailored to your needs.

Mark Mohn, director of attachments, Volvo Construction Equipment, explains that picking the incorrect bucket type or the cheapest bucket available is among the most common mistakes when selecting a loader bucket. “The correct bucket will pay for itself. We offer buckets for different applications, such as light material, rehandling, high-tip digging, etc. Each type has features designed to increase productivity for that specific application,” he explains. “For example, the rehandling buckets we introduced in 2016 deliver an increase in fuel efficiency due to the faster fill rate and reduced spillage.”

Size Buckets for the Material Density

Buckets must also be sized to the application. “Material density determines the capacity of the bucket,” says Sam Shelton, marketing manager, Hitachi. “Moisture is a function of the material density and will affect capacity, but is normally within a limited range. The abrasiveness of the material or impact potential determines the [bucket] material spec and thickness.”

“One of the most common mistakes made by contractors when selecting a bucket is choosing the wrong size for the wheel loader,” says Aaron Kleingartner, marketing manager, Doosan Infracore North America, LLC. “You should work with your local equipment dealer to help select a bucket that best matches the wheel loader, the application where the machine is working and the type of material the bucket is handling. Dealers have formulas available to calculate size and material density and compare it to the size of the bucket to provide the best solution for a contractor’s application.

The spade nose-style rock bucket is designed for heavy-duty digging applications. It features pin-on mounting and standard weld-on teeth.The spade nose-style rock bucket is designed for heavy-duty digging applications. It features pin-on mounting and standard weld-on teeth.“A good guide for selecting the most appropriate bucket is to calculate the average density of the material to be moved and then compare that to the tipping load and lifting capacity of the wheel loader,” he continues. “Also, consider that you may be working with multiple densities — sand one day, rock the next — so spec the bucket based on the heaviest material it will handle. A bucket properly matched to its material could decrease the number of passes needed to fill trucks.

Remember that material density can vary. “A lot of times when sizing a bucket for certain material, it is normal to oversee certain conditions, such as moisture level, which increases material density,” says Lucas Sardenberg, product marketing consultant, Caterpillar. “Note if the material is stored outside or inside, and the amount of rain for the site.” If there is a considerable amount of moisture and rain present, it might make sense to size the bucket for a higher density vs. using the standard definition used in most publications. “Don’t overlook this step since some customers end up with stability issues on loaders when the largest possible bucket was selected without accounting for heavier materials possibilities.”

But the correct bucket is about more than size. “Bucket volume alone is not an adequate measure of capacity of the loader,” says Mohn. “The crucial factor is the ability of the wheel loader to fill the bucket during every pass. For that reason, the right size and shape of the bucket is important. A large bucket can result in lower productivity because it is more difficult to fill, while a small bucket that is easier to fill can increase productivity.”

He adds, “A number of factors have to be taken into account, such as the nature of the material being handled, the condition of the wheel loader, the operator’s skill and the transport distance. If the transport distance is long, this may cause spillage. Since all of these factors vary, a wide selection of buckets is required in order to achieve maximum productivity.”

More Than Meets the Eye

Don’t be fooled by the simple appearance of the bucket. “Bucket selection might look simple as an afterthought, but all things considered, it is no easy task,” says Sardenberg. Often, contractors merely purchase the same bucket they have used in the past. “If something is working, why change it? The answer is because of advancements in technology and design.”

Many newer bucket designs are more efficient than the older buckets they may be replacing. “Gather all information on your application and rely on the equipment dealer to bring the tools needed to make a better decision that should pay back in no time,” says Sardenberg.

Bucket choice can even impact machine durability. “Wheel loaders are very versatile machines and can tolerate quite a variance in buckets without serious adverse effects,” says Shelton. “Most wheel loaders can handle a range of buckets, but the overall payload and stress on the machine will have an effect on the life of components and the overall durability of the machine.”

Caterpillar designed its Performance Series buckets for higher capacity (increased fill factors); less fuel burn as the bucket loads faster; increased tire life as materials load easier; and operator comfort as loads are easy to see early during the dig process.Caterpillar designed its Performance Series buckets for higher capacity (increased fill factors); less fuel burn as the bucket loads faster; increased tire life as materials load easier; and operator comfort as loads are easy to see early during the dig process.“Pushing a wheel loader beyond the recommended limits can accelerate wear, affect machine durability and significantly lower the contractor’s return on investment,” adds Kleingartner. “Manufacturers offer a variety of bucket weights, capacities and widths to try to help customers best match their application.”

It is all about profitability. “The correct match between the bucket and application can make the whole difference between making or losing money in productivity-oriented applications,” says Sardenberg. “Small details can have a large impact. Some buckets have a complete flat floor vs. others that have a very slight, subtle angle. In poor underfoot conditions, having the angle will certainly help the load cycle by ‘pinning’ the loader front tires when engaging the material.

“Similarly, consider what happens when a simple side plate went from a straight to a curved design,” he continues. “A lot more material gets retained in the bucket, but only if the material loaded can stack up on itself and not roll out.”

While most buckets tend to look the same, there can be large differences in actual performance. “Although it is very hard to differentiate buckets by their looks, the best way a customer can tell the differences in the multiple bucket offerings is doing a more detailed analysis,” says Sardenberg. “Assuming bucket capacity/overall design match, start with the plate thickness for the various parts of the bucket. Do they match or is a bucket considerably thinner than the other? If available, see if there is a specification on material hardness. Not all iron is equal. More hardness costs more, but will last much longer.”

Also look at wearable parts such as the edge, side cutters or teeth. “Does one manufacturer use considerably less material on those critical parts? Can they be flipped when worn? How about bolt or restraint device protection? Are those protected or recessed? Can they be changed quickly?” Sardenberg asks. “Look at the spill guard. Is it integrated into the design or does it look like it was just a welded plate or afterthought? Lastly, if the bucket is not manufactured by the same OEM as the machine, ask why that would be better.”

Caterpillar designed its Performance Series buckets for higher capacity (increased fill factors); less fuel burn as the bucket loads faster; more tire life (bucket loads materials easier); and operator comfort (bucket loads are easy to see early during the dig process). “To increase bucket fill factors, look at curved side plates and an integrated spill guard,” Sardenberg advises. “Both increase material retention for most materials.”

To ensure faster cycle times, consider the bucket floor, or distance between the edge and the part of the bucket that starts to curve. “A longer floor means material will have to travel further before rolling into itself, which helps with faster loads and cycle times,” says Sardenberg. “Don’t disregard bucket visibility during the machine cycle. The sooner the operator can see the load in the bucket, the less time he or she will spend on the digging portion when the bucket is full, which would waste fuel.”

Manufacturers such as Volvo have designed their buckets to be optimized for their loaders. “Floor-to-back ratio, floor depth, side plate design and cutting edges all have effects on the fill rate,” says Mohn. “If you can fill the bucket faster and easier and at lower machine rpm, the operator will save time and fuel.”

Match Bucket to Application

Several steps can be taken to select the most appropriate bucket for an application. Start by gathering all available information about the task(s) or application to be performed.

“Is the material loose? Well shot or poorly shot? What is the material, its density, abrasion, etc.? Don’t forget to note constraints, as well, such as truck rail height if loading trucks, or hopper height/width. Get all the details on the current machine performing the work today, including its configuration,” Sardenberg advises. “Finally, if you have productivity data and targets, have those ready, as well. A good tip is to use scale house data in yard load-out applications. Last, but not least, operator level of expertise and training should be considered in selecting the proper tool.”

Once compiled, use the dealer to make sense of the data. “Manufacturers should be able to pinpoint the tool that will maximize machine performance while minimizing operating cost for higher margins,” says Sardenberg. “Never compromise on a standard solution just because it is easy and readily available.”

Buckets with flat floors, such as this general-purpose bucket from Volvo, can improve cycle times with faster loading.Buckets with flat floors, such as this general-purpose bucket from Volvo, can improve cycle times with faster loading.Take general-purpose buckets, for example. “General-purpose buckets have a wide application gamut. But as with everything that is made to work relatively well in most applications, you can get the ‘Jack-of-all-trades, but master of none,’” Sardenberg comments.

Many times you must consider more than one application when choosing a bucket. “General-purpose buckets are the most common bucket design for maximum filling and material retention,” says Kleingartner. “This design works best in day-to-day material handling or when working in a wide range of densities, such as general aggregates in construction.”

Shelton adds, “They are called general purpose because they fit most applications. Material handling buckets are for slightly lighter material and are slightly larger capacity. For the more extremes in materials, you really need to get the manufacturer’s recommendation because bucket weight and dimensions can influence the ultimate capacity.”

In specific applications, swapping out buckets makes sense. “If an operator needs to move larger loads with smaller densities, a light material bucket may be an economical solution,” says Kleingartner. “Light material buckets offer higher capacities than general-purpose buckets, making them ideal for lifting snow, mulch or other light materials. Another option is a multipurpose bucket, which can load, carry and dump granular materials; grab irregularly shaped objects; and doze, level or spread and fill. For more abrasive applications, contractors may want to consider a spade nose-style rock bucket. Typically, they are designed to move higher density materials such as those found in quarries, mines and larger road work and site development.”

Production applications should be paired to specific buckets. “If the machine is being used in a production application like an asphalt plant, sand quarry, loading application, etc., it should have a bucket designed for that application,” says Mohn.

“If a contractor does a variety of work, such as digging and material handling, it may be more efficient to purchase multiple buckets to ensure the operator is using the correct bucket for the task,” says Kleingartner. “With a hydraulic quick-coupler option, the operator can easily change attachments from the comfort and security of a wheel loader cab.”

Purchasing Multiple Buckets

In some cases, multiple buckets may be justified. “In the event of two different applications where the loader splits the time 50/50, if one can benefit from higher productivity, an assessment should be made to weigh the potential increase in productivity vs. the cost to run two tools,” says Sardenberg. “With the wide availability of couplers, tool switch time can be minimized.

Wlo Att Flat Floor Bucket“However, remember that some coupler designs can potentially impact machine performance and bucket sizing,” he adds. “Don’t forget to consider transportation costs. Usually, a loader can be transported on a single flatbed, while adding a bucket might require a different setup if the sites are not located in the same area.”

Multiple buckets may also be required if you have two or more very diverse applications. Some buckets simply will not hold up if used in the wrong application. “The loader may spend 80% of its time handling sand and gravel [for which] a material handling bucket is ideal, but 20% of the time it is handling recycled concrete or asphalt, which damages a material handling bucket’s lighter shell,” says Wayne Powell, adviser to the vice president, Hitachi.

Tool Selection

“Contractors who work in rugged, difficult soil conditions may want to add ground-engaging tools (GET) to enhance the performance of their wheel loader and bucket,” says Kleingartner. “Cutting through material can be made easier with GET such as rugged bucket teeth. Many manufacturers, like Doosan, offer a vast number of interchangeable bolt-on teeth options for general-purpose, light material and multipurpose buckets. Weld-on teeth are typically offered for heavier-duty buckets, such as rock buckets.”

“Cutting edges and tooth type have a big impact on penetration,” says Mohn. “Spill guards help keep the material in the bucket and can increase efficiency. The material type and application should determine what type of wear parts are needed.”

“The impact of the GET and other bucket attachments cannot be overstated enough,” says Sardenberg. “First, they need to match the application and material they are used mostly on. For application, remember that a bucket might also be used to clean up the loading floor or even to level grade in some cases by backdragging. Tougher materials will require special tips and edges to penetrate and break the material as the load cycle happens.”

Because adding protection such as wear plates also adds weight, which can affect productivity, be sure to verify machine performance/capacity. “For most common bucket applications, we recommend to ensure the bucket spill-guard is part of the basic bucket design,” says Sardenberg. “This simple add-on prevents material spillage in the machine linkage and components, which extends the life and avoids issues such as materials rolling down the linkage and into the cab glass.

“Because of the multiple options,” he adds, “we strongly suggest to work with dealers and manufacturers to find the perfect match of application, performance and durability for bucket tool selection.”