Choosing an excavator for your job is only the first step in acquiring the tools you need. Whether they’re mini or large, excavators are incredibly versatile because of the available bucket and attachment options. Given the many types of backhoe and excavator buckets on the market, a lot of factors contribute to finding the right bucket for the job.
Choose an Excavator Bucket That Suits Site Conditions
When choosing an excavator bucket, the first thing to consider is the specific application and type of material you are handling. You typically want to find the biggest bucket for your job, taking into account the material density and the size of the hauler truck.
Remember the weight of the bucket limits your cycle time, and the bucket only becomes heavier when loaded with heavy materials. As a rule of thumb, use a smaller bucket for higher-density materials to avoid slowed productivity. You want to be able to load your hauler truck quickly with as few cycles as possible to reduce fuel consumption, wear, and downtime.
Different applications can also require specific types of buckets. For example, you wouldn’t be able to dig an 18-inch trench with a 30-inch bucket. Some buckets have features to handle certain types of materials. A rock bucket has a V-shaped cutting edge, and long, sharp teeth that can break through hard rock and push heavy loads with more power. A digging bucket is known to handle hard soil. Consider the type and density of your material and ensure you select a bucket that is capable of lifting it.
Excavator Bucket Types
An excavator can do anything from digging trenches and laying pipes, to landscaping and moving snow. Several bucket types enable an excavator to handle various materials within these applications. While there are also many specialty buckets available, the five most popular buckets include:
- General-purpose, all-purpose, or digging buckets
- Grading, cleaning, or ditching buckets
- Heavy-duty or severe-duty buckets
- Trenching buckets
- Angle tilt buckets
What Is a General-Purpose Bucket?
A general-purpose bucket has the most versatility and is appropriate for many excavating tasks. It is also known as a digging bucket, and it is the standard attachment that comes with an excavator. If you rent an excavator without specifying a bucket, you’ll probably receive a general-purpose bucket. It comes with short, blunt teeth that work great on soil and are available in many sizes for various applications.
Here are some of the materials you can move with an all-purpose excavator bucket:
- Ground with loose gravel or stones
- Frost-covered soil
You can also find wear-protection components to allow an all-purpose excavator to work with more abrasive materials.
What Is a Grading Bucket?
Grading buckets stand out for their smooth edges, wide construction, and flat cutting edges. They also have lift eyes, weld-on side cutters, and reversible bolt-on cutting edges. This construction creates smooth edges for all digging areas and works best with soft materials and soils. Grading buckets, also called clean-up or ditching buckets, have a lot of versatility for loading material, grading, leveling, back-filling, sloping, and cleaning ditches for improved drainage.
When you know how to use a grading bucket, you can use it for many applications, including:
- Ditch maintenance
- Slope shaping
- Road construction
- Utility work
What Is a Heavy-Duty Bucket?
A heavy-duty or severe-duty bucket is usually made from high-strength, abrasion-resistant steel. Because of their superior durability, these attachments are often used in rock quarries to load trucks with high-density material in fewer passes.
Cat® excavator buckets come in general-, heavy-, severe-, and extreme-duty varieties. They provide enhanced digging for heavy or abrasive materials, such as:
- Blasted rock
- Hard-packed clay
- Sharp rock
- Ripped basalt
- High-silica sand
- Shot granite
Severe- and extreme-duty buckets can handle even heavier materials, including:
- Broken slag
What Is a Trenching Bucket?
Like a grading bucket, a trenching bucket is used for trench digging. It works well for narrow cable trenches, pipe culverts, and drains. It has a narrow shape, a sharp, flat blade, and an extended front section for better access. This tool can dig deep trenches while maintaining a fast cycle time. A trenching bucket should be used for high-precision jobs, such as digging around pipes.
What Is an Angle Tilt Bucket?
An angle tilt bucket has many of the same applications as a grading bucket — with the added feature of 45-degree rotation in either direction. Because of the tilting ability, these buckets are useful for creating precise slopes. They also allow an excavator to move or shape more land without changing positions as frequently. These features may allow you to experience increased uptime with heavy-duty construction.
Angle tilt buckets come in many sizes for a variety of applications, such as:
- Ditch cleaning
- Clearing land or snow
- Digging in hard-to-reach areas
What Types of Specialty Excavator Buckets Are Available?
Besides the most commonly used buckets, you can find a variety of specialty bucket designs to use for specific jobs:
- Riddle bucket: Sometimes called a skeleton bucket, a riddle bucket has heavy plates with gaps in between. Small particles fall through, sifting out coarse soil or rocks from fine soil.
- V-bucket: As a special kind of bucket for trench-digging applications, a V-bucket can dig long, angular, V-shaped trenches. It’s often used for laying pipes and utility cables.
- Rock bucket: A rock bucket has a similar design to general-purpose digging buckets. It has long, sharp teeth with a V-shaped cutting edge for optimal pushing power. The rock bucket can break through hard rock with ease.
- Hard-pan bucket: A hard-pan bucket has a similar design to a rock bucket and comes with attached ripper teeth on the back of the bucket. It can loosen compacted soil while digging.
Renting or Buying Used Excavator Buckets? Know What to Look For
With so many types of excavator buckets, it’s a good idea to consider renting one when you need to accomplish a particular task. If you plan to use the bucket for many jobs, you can save money by buying a used excavator bucket. If choosing a previously owned or rented bucket, you need to understand how to inspect for damage or repairs. Look for the following elements:
- Cracks, bends, and dents: The weld points on the bucket may develop cracks, dents, or bows. A fissure in the welding will appear to have a fringe of rust.
- Rust:Rust is one of the signs of excessive wear in an excavator bucket. If you spot rust, consider whether you can refurbish it or if the bucket is in too poor condition.
- Scalloping: Excavator bucket teeth material is a low alloy steel made for strength and durability. Over time, if the bucket teeth are worn, they will take on a half-moon shape. Scalloped teeth are still operational, with some reduced efficiency. If the teeth are worn down, you may consider investing in replacement teeth or plan to replace them soon.
- Parts availability: The bucket’s teeth and other customization features will eventually wear out. If the bucket is a discontinued model, you may have trouble finding replacement teeth. Before you buy, check online to see where you can buy the correct parts and if they are affordable and easy to find.
- Fit:Whether you rent, buy new, or buy used, the bucket needs to fit your excavator. A bucket that’s too heavy for your excavator size will be inefficient and even damage your machine. Once you have checked to ensure it is the correct size and weight for your excavator, attach it to ensure a proper fit.
- Play or movement: Once the bucket is attached, try to open and close the bucket. Check for looseness in bushings, pins, or couplers.
- Dig:If everything is in working order, try digging with the bucket to ensure it works. Consider the cycle time you can achieve compared to other buckets.
Selecting an Excavator Bucket Size
Most construction projects benefit from a bucket that will increase productivity by reducing the number of passes the tool needs to make. Select the biggest excavator bucket that won’t compromise efficiency—except when you have a particular size requirement, like when digging a trench. Remember that the bucket you use on a 20-ton excavator would be far too big for an 8-ton excavator. A bucket that’s too big will require the machine to do more work, and each cycle will take longer, reduce efficiency, or cause the excavator to topple over.
Excavator Bucket Size Chart
Generally, a range of bucket sizes will work for the excavator you have. Mini excavator bucket sizes can range from specialty 6-inch buckets to 36-inch buckets. Keep in mind that some sizes only apply to grading buckets, and you shouldn’t use other types of buckets with those dimensions. To see what size of bucket is possible for the weight of your excavator, use this sizing chart:
- Up to 0.75-ton machine: Bucket widths of 6 inches to 24 inches, or 30-inch grading buckets.
- 1-ton to 1.9-ton machine: Bucket widths of 6 inches to 24 inches, or grading buckets 36 inches to 39 inches.
- 2-ton to 3.5-ton machine:Bucket widths of 9 inches to 30 inches, or 48-inch grading buckets.
- 4-ton machine: Bucket widths of 12 inches to 36 inches, or 60-inch grading buckets.
- 5-ton to 6-ton machine: Bucket widths of 12 inches to 36 inches, or 60-inch grading buckets.
- 7-ton to 8-ton machine: Bucket widths of 12 inches to 36 inches, or grading buckets from 60 inches to 72 inches.
- 10-ton to 15-ton machine: Bucket widths of 18 inches to 48 inches, or 72-inch grading buckets.
- 19-ton to 25-ton machine: Bucket widths of 18 inches to 60 inches, or 84-inch grading buckets.
How Is Excavator Bucket Capacity Calculated?
Each job’s bucket capacity depends on the size of your bucket and the material you are handling. Bucket capacity combines the material fill factor and density, the hourly production requirement, and cycle time. You can calculate your bucket’s capacity for a particular project in five steps:
- Find the material weight, expressed in pounds or tons per cubic yard. Refer to the Fill Factor Data Sheet provided by the bucket manufacturer to find the fill factor for that particular material. This figure, expressed as a decimal or percentage, specifies how full the bucket can be with this type of substance.
- Find the cycle time by timing a loading operation with a stopwatch. Start the timer when the bucket begins digging and stop when the bucket starts to dig a second time. Take 60 divided by the cycle time in minutes to determine cycles per hour.
- Take the hourly production requirement — set by the project manager — and divide it by the cycles per hour. This calculation gives you the amount in tons moved per pass, known as the per cycle payload.
- Take the per cycle payload divided by the material density to arrive at the nominal bucket capacity.
- Divide the nominal bucket capacity by the fill factor. This number tells you exactly how many cubic yards of material you will be able to lift with each cycle.
Excavator Bucket Customization and Accessories
To tool your excavator bucket for whatever applications you have in store, you can customize the bucket with many add-on features:
- Teeth types: One of the most common ways to customize an excavator is with different kinds of teeth on the front of the bucket. Teeth come in many shapes for various purposes. Chisel teeth have a smooth, angled tip with a flat bottom and are great for most applications. Rock chisel teeth have a strengthened chisel tip, suitable for rock and hard ground. Single tiger teeth have a pointed tip for good material penetration. Twin tiger teeth have two sharp prongs per tooth for even better penetration.
- Teeth spacing: You can also adjust the teeth spacing for different applications. Wider-spaced teeth can achieve better penetration in rock, while tighter teeth configuration work better in soil and trench digging.
- Edge configuration: Buckets can have either spade or straight edges. A spade edge works best for harder materials and quarry applications. Straight edges provide a cleaner cut in soil work, trenching, and site development.
- Side cutters:Excavator buckets typically come with side cutters that are thicker than the side of the bucket. You can customize your bucket with additional bolt-on side cutters, also called root cutters, to help you dig through roots while excavating.
- Wear protection: Side cutters can also contribute to wear protection, alongside bottom and side wear plates, and sidebar protectors. These accessories will lengthen the life span of your bucket.
- Quick coupler: Excavators have many types of bucket attachments and can hold other attachments such as rippers, augers, rakes, and grapples. Being able to switch out accessories around your job site is crucial. A quick coupler lets you easily switch between many types of tools and buckets.
- Power-tilting coupler: A power-tilting coupler enables any tool to tilt along a 180-degree arc, or 90 degrees left or right of center, for the most precision.
- Thumb: For bulky or irregularly shaped loads, an excavator thumb can attach to the top of the excavator bucket to pinch material and keep it in place.
Changing Teeth on Excavator Buckets
The best time to replace the teeth is before they wear down entirely and expose the bucket adapter. To fit the bucket with new teeth, follow these nine steps:
- Begin with safety glasses and safety boots. You’ll need a hammer, a pin removal tool, a wire bristle brush, and the new teeth you wish to insert. For safety, tag out the machine before working on the bucket.
- Position the bucket so the teeth are parallel to the ground.
- Using a pin-removal tool, remove the existing teeth. Hammer the pin removal tool into the pin, so you are pushing against the retainer side of the tooth.
- Take the tooth off, and clean up the tooth adapter with a bristle brush.
- Insert the retainer into the corresponding recess in the adapter.
- Keeping the retainer in place, position the tooth on the adapter.
- From the opposite side of the retainer, insert the pin through the tooth and tooth adapter.
- Hammer the pin until it is flush with the end of the tooth.
- Check to ensure the recess in the pin is locked in place within the retainer.
Find Cat Excavator Buckets and Attachments From Thompson Tractor
When you’re ready to shop excavator buckets or need expert advice for your job site and machine, partner with the local leaders in tractor parts and repairs. We have a wide selection of Cat equipment attachments for excavators — whether you’re in the market for new or used buckets. Get the parts you need fast from the experts with over 60 years of experience in the business.
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