Demolition Questions: How Does a Jackhammer Work?

(4-min read)

Though modern demolition utilizes an array of tools and methods, the jackhammer remains the tool most synonymous with professional demolition sites. Whether used to break apart asphalt or concrete or to make a hole in which to place an explosive charge, jackhammers are incredibly powerful and versatile tools for demolition professionals. Despite appearing to be magic road-munching instruments, the mechanics of jackhammer are reasonably straightforward and have remained mostly unchanged for over 200 years.

Varieties of Jackhammer

Also known as a pneumatic or demolition hammer, a jackhammer operates differently based on its power source. The first jackhammers were exclusively steam-powered, though today they are primarily electro-magnetic and air-powered. For the sake of this article, we will be discussing the most popular variety — the air-powered jackhammer.

Internal Hammer, External Bit

A jackhammer works utilizing an internal hammer being repeatedly forced against a bit. An air-powered piston pushes the hammer to make actual contact with the bit, which explains the tremendously loud noise produced by the device. The piston forces the hammer against the bit and the bit into whatever the operator intends to pulverize. The reversed air flow of the device allows for near-instantaneous resetting for the rapid hammering of the internal bit around 25 times a second.

Good Vibrations

Most jackhammer bodies are made of forged steel to allow for a stronger cylinder that contains the moving and colliding components. The various parts that make up the body of the jackhammer are bolted together — a construction most resistant against the intense vibrations generated by the hammer. While the frames of other tools may be welded, welds likely wouldn’t hold up to these rock-breaking vibrations.

Compressed Air Power

The jackhammer contains an internal piston that is pushed by highly compressed air. Once the hammer reaches its lowest point after hitting the device, some air vents out after the hammer strike and a valve then flips to use some of the forced air to return the hammer to a raised position within the body of the device.

Types of Bits

The jackhammer bits can be changed out as they become worn or when a different style of bit is required. Pointed bits may be used to pulverize a hardened material. Flat-tipped bits are used for more controlled finishing of edges. There are also different style bits depending on the material being crushed, the depths required, and other factors.

Hazards of Jackhammering

Jackhammers are among some of the most dangerous pieces of equipment on a demolition site — and not for reasons you would immediately guess. Yes, you can damage your foot with a bit. Jackhammers are also incredibly hazardous to your hearing and can launch debris into your eyes. Another hazard is from your body sustaining the tremendous vibration from the hammer collision — a condition known as Hand-Arm Vibration Syndrome or HAVS. HAVS can result in nerve damage, loss of grip, and other symptoms — both reversible and permanent. To prevent HAVS, jackhammer operators must take frequently take breaks in a single hammering session.

Safety First

Any demolition team worth their salt will always take safety very seriously. Jackhammer operators should always wear protective boots, ear protection, eye protection, and a hard hat. At DT Specialized Services — demolition professionals in Tulsa, OK — we take every precaution to ensure a safe and productive work environment.