Understanding Drum Brakes: Function, Features, and Maintenance Tips

Every industry aims for maximum efficiency and safety. One minute of unplanned downtime costs companies thousands of dollars. In fact, 98% of industrial organizations say one hour of downtime costs them at least $100,000.

Regular equipment maintenance reduces potential downtime, thus reducing the chance of losing money. But having the right equipment and knowing how it works is also important.

In this guide, we answer the question, “What are drum brakes?” and explain how they work.

What are Drum Brakes?

The average person may immediately think of automobiles when they hear the term “drum brake.” But for more than half a century, the marine, mining, and energy industries all used drum brakes. Since then, drum brakes have evolved to fit the needs of dozens of industries.

Industrial brakes get subjected to much harsher applications than auto brakes. In most cases, industrial brakes operate in harsh conditions and in remote locations. Safe and efficient drum brakes meet AISE or DIN standards.

How do They Work?

In drum brakes, the brake lining attaches to a shoe. The most common drum brake design has two shoes mounted on either side of a drum.

How drum brakes work is air or hydraulic pressure presses the shoes onto the drum which causes friction. The friction causes deceleration.

When choosing a brake for your application, you must consider the braking torque. Drum brakes come in many sizes, so you have to select the right model that dissipates the energy during stopping without overheating.

In general, you determine torque by the drive motor. For cranes, this should be 75-100% of drive motor torque. For crane hoists and other similar applications, the factor is 150-200% of the motor torque.

Size and weight are important in mechanical brakes. Common size considerations for friction brakes include:

• Drum thickness
• Drum diameter
• Total pad area
• Wearable friction area (the surface area of the brake lining)
• Running clearance (distance between the brake lining and surface area when brakes aren’t engaged)
• Lining thickness

Reputable drum brake manufactures can also machine drum brakes to your specifications.

Drum Brake Components

Drum brakes consist of 12 components:

• Wheel cylinder
• Upper return spring
• Push rod
• Adjuster wedge
• Adjuster spring
• Parking brake cable
• Lower return spring
• Parking brake arm
• Hold down spring
• Shoe
• Spindle
• Locating spring

All these components work to slow the machine. You should also know how to install and replace drum brakes to reduce the amount of machinery downtime. Simple troubleshooting can save you time and money if your machine isn’t working as efficiently as it should.

What is Their Application?

Drum brakes get used in many different industries. The industries with the most common applications for drum brakes are:

• Material handling
• Marine
• Mining
• Oil and gas rigging
• Military
• Agriculture
• Forestry
• Construction

While the auto industry has switched to disc brakes, other vehicles like cranes and heavy machinery still use drum brakes. Drum brakes allow heavier workloads that need increased torque.

Keep Your Heavy Machinery Operating

Your machinery makes you money, and when it’s not operating at peak efficiency, it’ll cost you money too. Now that the questions, “What are drum brakes and how do they work” have answers, you’ll understand the engineering of your machinery better.

You should also have a better understanding of the importance of quality drum brakes. That’s where Kor-Pak comes in.

Kor-Pak Industries provides parts to some of the biggest names in manufacturing. We sell quality products and build special orders. Visit our product page for more info or contact us with any questions.