TPB-90 Handheld Pneumatic Jackhammer, aks paving breaker, has been rebuilt to like new condition by a professional air tool mechanic. TPB Series handheld pneumatic jackhammer has for models as TPB-30
Model TPB40 TPB60 TPB90 Piston diameter 44mm 57.15mm 66.67mm Piston stroke 100mm 146mm 152mm Impact frequency 900 minute/Time 1250 minute/Time 1400 minute/Time Net weight 18kg/39.6lbs 30kg/60lbs 42kg/92.4lbs Total length 660mm 645mm 723mm Air consumption 1.6m3/minute 2.0m3/minute 2.2m3/minute Hose size 19mm(3/4inch) 19mm(3/4inch) 19mm(3/4inch) Shank specifications 14-1/4 25X108 14-1/4 25X108 14-1/4 25X108 Inlet size 3/4pt 3/4pt 3/4pt Air pressure 0.63Mpa 0.63Mpa 0.63Mpa
One of the most recognizable tools in demolition, the jackhammer is a large, powerful device designed to break up hard materials such as concrete, asphalt, and the like. You have seen jackhammers mostly used for street repair work, although they originated in the mining industry. They bust up the old materials so that new concrete or asphalt can be put back in place. Jackhammers are also used to break up rock for mining or road construction purposes.
As the name suggests, a jackhammer is a device that creates a hammering action to break up hard materials such as rock, concrete, asphalt, and the like. It can also be used on even harder materials such as metal or softer materials such as wood, but it is not recommended or nearly as effective. Depending on the design and size of the tool, the hammer mechanism inside the tool is driven either by compressed air (pneumatic), electro-mechanical force, or by hydraulics.
While rock is quite strong, it is also quite rigid which makes it well-suited to be broken up by a jackhammer. They are sometimes called demolition hammers, which is mostly a term used in the UK. However, a demolition hammer is a smaller variant of jack hammer. You can distinguish a jackhammer from a demolition hammer by looking at the shape of the handle. The jackhammers have a T shaped handle whereas the smaller demolition hammers come with L-shaped or D-shaped handle.
Rotary Hammer Drill & Combi Drill: These are handheld devices that is usually smaller than a jackhammer. In these tools, the drill bit rotates as well as moves back and forth to create a hammering action. However, instead of a special clutch that is used in jackhammers, it uses a unique piston system. This is different than a hammer drill and makes it useful for breaking up smaller items.
Is using a jackhammer bad for you? Operating a full-size jackhammer can be dangerous due in large part to the noise that the device makes. Earmuffs or earplugs are required when using jackhammers to prevent hearing loss. There is also a condition known as Raynaud Syndrome which is associated with prolonged use of jackhammers. The syndrome leads to what is known as vibration white finger in which the mobility of the fingers is affected.
Prolonged use of a handheld jackhammer can lead to nerve damage in the fingers and hands along with the integrity of the blood vessels being affected. In rare cases, fingers have had to be amputated. In addition, many who have used jackhammers regularly have suffered from carpal tunnel syndrome.
Many handheld jackhammers today use dampening materials to reduce vibrations. There are also rules on construction or demolition sites on how long a handheld jackhammer can be used by a single person. This has helped to reduce unwanted side effects.
The very first jackhammer was created by Samuel Miller. In 1806, Miller patented a steam-powered drill that uses the same principles as a modern jackhammer. However, the steam was only used to raise the drill and not for the pounding action. By 1844, C. Brunton proposed a pneumatic drill for mining purposes. And two years late Thomas Clarke, John Varley, and Mark Freeman created a jackhammer that used either steam or pressure from the atmosphere to work.
Over the next several years, the jackhammer was perfected thanks to the addition of a piston and compressed air to make it more efficient in operation. The obvious use for mining evolved into creating large tunnels for roads and train tracks. By the 20th century, jackhammers had evolved to become more efficient and used for road construction and repair work.
The principle used for jackhammers is based on applying a percussive force in repeated actions on the material that needs to be broken up. Although how the percussive force is applied can be different depending on the power source of the jackhammer, the principle is the same.
A jackhammer bit, usually a large chisel, is attached to the end of the device which moves it back and forth to create a percussive impact. The repeated impacts over a short period helps to break up strong, yet rigid material such as stone. The material is broken into smaller pieces that can be removed later.
The limitation of the handheld jackhammer is based on the strength of the person who uses it. For example, trying to use a jackhammer on vertical surfaces such as walls or along steep slopes is not practical as the weight of the device makes it difficult to lift and control at the same time. This is where rig-mounted jackhammers come into play.
Jackhammers can be divided into two categories, handheld and rig mounted. As the name implies, the smaller jackhammers are held by hand, although they are still quite large and powerful. Rig mounted jackhammers are larger and more powerful, normally used where a handheld jackhammer would not practical.
The pneumatic jackhammer, also known as a pneumatic hammer or drill, uses compressed air as its power source. This type of jackhammer has an air compressor that is powered by an engine, usually diesel-fueled. The older versions used a reciprocating compressor that engaged a centrifugal clutch. This meant that when powered, the jackhammer was either idle or running at maximum speed.
Newer versions of the pneumatic design are powered by a rotary compressor. They are quite large and usually rig-mounted. Its common to see newer designs using an electrical generator as part of the power function. While operating in the same basic manner as the old reciprocating compressor, the newer versions are longer-lasting thanks to the pneumatic lubricator that is attached to the air hose.
These are handheld jackhammers which generally are quite small compared to pneumatic versions. As the name indicates, it is powered by an electric motor that rotates the crank that moves the chisel part of the jackhammer. There are two pistons present, a drive, and free flight version.
The device operates with the crank moving the piston back and forth all within the same cylinder. However, the piston itself never touches the free-flight piston. Instead, the compressed air that comes from the drive piston is what drives the flight piston to hit the striker which in turn contracts with the bit.
Electric jackhammers are normally plugged into an outlet. They are generally small and may weigh as little as 12 pounds. They are small enough to be easily handled, so they are normally used for demolition work inside a structure. This type of jackhammer is quite versatile, although because of its small size it takes longer for it to break apart hard materials over a large space compared to other types of jackhammers.
This type is so large that it is normally rig mounted. You will often see them on backhoes or excavators. While sometimes used for street repair work, they are most often seen in large-scale mining, construction, and demolition operations. Although large and heavy, a hydraulic system is smaller and more efficient compared to pneumatic systems. It is also cheaper to build and more powerful as a result. Because they are rig mounted, they can be used against both horizontal such as the ground or roads and vertical surfaces such as walls or the sides of a hill or mountain. They can even be used against ceilings depending on if the arm can be turned in such a direction. The power of the jackhammer comes in large part from the vehicle which carries it.
The device uses a hydraulic breaker which is attached to a hydraulic motor that is inside a hammer system that is sealed. This separation is important because the impact of the hammer may damage the pump system used to produce the hydraulic power if it were directly connected.
What is a jackhammer used for? The primary use of a jackhammer is to break up rock-like materials. They were first used to break apart rocks in mining operations. Then, they were used to help construct tunnels as they could break up the rocks that normal digging tools would have a difficult time removing.
Today, they are mostly used to break apart concrete and asphalt on roads. The hammering action creates percussion which vibrates the rigid rock material and causes them to be broken up into smaller pieces.
For road repair work, the pneumatic hammer is used to break apart old concrete or asphalt around a crack or pothole so that new material can be poured into place. This creates a cleaner, longer-lasting repair compared to simply filling in the hole as it existed. The jackhammer can easily break apart the old, compromised material so that it can be shaped to accept new material and patch the surface area.
Twenty thousand years ago, if you'd needed to dig a hole in rough ground, chances are you would have found yourself swinging a sharpened deer antler over your head. Modern pickaxes are based on pretty much the same idea. The long wooden handle and heavy metal blade build up energy as you swing, focusing it on a single, narrow point so each blow produces maximum force and pressure. It's simple technology, but it's very effective.
Today, if you want to dig a hole in a hurry and there's a thick lump of concrete or asphalt in your way, you're most likely to use a jackhammer, also known as a pneumatic (air-powered) drill, rock drill, or pavement breaker. A strong and skilled road worker can swing a pickaxe 10 times a minute or more, but a jackhammer can pound the ground 150 times fasterthat's 1500 times a minute! Pretty amazing, but how exactly does it work?
Photo: Jackhammers aren't just used for construction: since they offer the fastest way of breaking through concrete and stone, they're often vital tools in emergency rescue work. Here, a worker from the US Naval Air Station Sigonella Fire and Rescue Team is using a pneumatic jack hammer to smash through concrete during a training exercise. Picture by Gary A. Prill courtesy of US Navy.
You've probably never handled a jackhammer, but you use exactly the same technology every time you ride on a bicycle or travel by car. The rubber tires that carry you smoothly down the road are inflated with air, so the force of your weight pushing down is exactly balanced by the pressure of the air pushing you upward. Tires are a simple example of pneumatic technology, which means they use the force of air pressure. (You may have heard of a similar technology called hydraulics that uses the force of liquid pressure.)
You can't see air, but it's a surprising thing. It's a mixture of gases, mostly nitrogen and oxygen, with its molecules constantly zooming back and forth like angry bees. When air is trapped in a container, such as a bicycle tire, molecules of gas are repeatedly crashing into the rubber walls and bouncing back again. Each time one of these collisions happens, the molecules give a tiny push to the rubber. With millions of collisions happening all the time, the air exerts quite a pressure (defined as the force acting per unit of area) on the rubberand that's what keeps the tire inflated. (The hotter the air is, the faster the gas molecules move, the more energetically they collide, and the more pressure they exert. That's why tires inflate more on hot days and after a long car journey.)
You might have seen pneumatics in action elsewhere. Blowpipes are another good example. When those angry savages from your comic books blow poisoned darts at their enemies, they're using air pressure to force a missile down a tube at high speed. In olden days, big department stores used pneumatic transport tubes to send money or messages rapidly from one floor to another.
Steam engines use pneumatics too; instead of air, they use high-temperature, high-pressure water vapor (steam) to push pistons back and forth and turn wheels at high speed. Vacuum cleaners, which use suction to remove dirt from soft furnishings, use the same principle in reversesucking air in rather than blowing it out.
Photo: A construction worker using a pneumatic drill. Note the red compressed air hose coming out of the left-hand side of the drill, which is supplied by the large green portable air compressor (marked Sullair), hooked up to the pickup truck on the left of the photo. Picture by Renae Kleckner courtesy of US Air Force.
Artwork: This little animation shows what happens inside a drill. Note how the blue valve at the top flips back and forth so the air changes direction. This makes the orange piledriver pound up and down, bashing the gray drill bit repeatedly into the ground. Note that this is a considerable simplification of what happens in a real drill, where the arrangement of valves, air passages, and so on is much more complex. You can get a sense of how much more complex real drills are from the illustration of Charles Brady King's original drill design, below.
Back to jackhammers. The first time you saw someone digging a hole in the road with a tool like this, you probably thought the equipment was electric or powered by a diesel engine, right? In fact, the only energy involved in making a jackhammer pound up and down is supplied from an air hose. The hose, which has to be made of especially thick plastic, carries high-pressure air (typically 10 times higher pressure than the air around us) from a separate air-compressor unit powered by a diesel engine.
The air compressor is a bit like a giant bicycle pump that never stops blowing air. When the worker presses down on the handle, air pumps from the compressor into the jackhammer through a valve on one side. Inside the hammer, there's a circuit of air tubes, a heavy piledriver, and a drill bit at the bottom. First, the high-pressure air flows one way round the circuit, forcing the piledriver down so it pounds into the drill bit, smashing it into the ground. A valve inside the tube network then flips over, causing the air to circulate in the opposite direction. Now the piledriver moves back upward, so the drill bit relaxes from the ground. A short time later, the valve flips over again and the whole process repeats. The upshot is that the piledriver smashes down on the drill bit over 25 times each second, so the drill pounds up and down in the ground around 1500 times a minute.
Jackhammers, and the air compressors that power them, come in all different shapes and sizes. The drill bits on the end are interchangeable too. There are wide chisels, narrow chisels, and tools called moil points for fine work. A skilled drill operator can loosen chunks of road in just 10-20 seconds, making light work of what our ancestorswith their antler pickswould have found truly backbreaking work!
King's design is a more elaborate version of the one I've sketched out in my animation up above, but essentially works the same way with a reciprocating (back-and-forth) valve making air move first one way and then another, moving a piston up and down, and bashing a drill bit repeatedly into the ground. I've colored the valve in blue and, in this design, it shifts from side to side, changing the way air flows between the inlet ports (colored yellow) and outlet ports (colored brown).
How does it work? When the valve is in the position shown here, air enters through the thick yellow hose at the top and follows the thinner paths shown in yellow, pushing the piston (red) downward and smashing the hammer (green and gray) into the ground.
Here's a small selection of three early jackhammers on record at the US Patent and Trademark Office, including King's. You can find many more examples if you search for "pneumatic drill" or "jackhammer" at the USPTO website (or on Google Patents):
Photo: Look, no compressor! Electric jackhammers like this Bosch Brute run off any standard 115/120-volt electricity outlet or 2500-watt portable generator. Mechanically simpler, they're also much lighter; this one weighs just 29kg (63lb). Noise rated at 105dB, it's still horribly loud, but significantly quieter than many pneumatic drills. Photo by James Fisher courtesy of US Air Force.
Not all jackhammers use compressed air, so it's a bit misleading to refer to them all, generically, as "pneumatic drills." Some are driven by powerful electric motors, which rotate a crank or cam that converts the motor's spinning (rotary) motion into back-and-forth (reciprocating) motion, pumping a piston, forcing a small air cushion back and forth, so powering a second piston connected to a shaft that repeatedly hammers the drill or other tool. Electric jackhammers have the big advantage that you can operate them without a separate air compressor unit (you can use them wherever there's an electric power supply), though they sometimes struggle to cut through the thickest rock.
Other jackhammers are operated hydraulically so, instead of using compressed air, they're powered by a continuous stream of hydraulic fluid (perhaps oil or water with additives). This flows through a hydraulic motor or turbine, powering a crankshaft and piston that hammers the drill bit. Hydraulic jackhammers are often used for underground mining where pneumatic tools are less suitable. Sometimes the hydraulic fluid that powers the drill is also used as a "cutting fluid" (for cooling and lubrication).
Because pneumatic jackhammers are incredibly noisy, engineers are constantly trying to develop quieter ways of achieving the same end. Perhaps surprisingly, much of the noise that a jackhammer makes comes not from the shattering pavement but from its own internal mechanismthe piledriver banging against the drill bitso making a quieter machine means designing a hammer that works in a different way. In 2000, Brookhaven National Laboratory produced a helium-powered hammer called RAPTOR that worked like a high-speed rifle, firing tiny steel nails into rock to break it apart. NASA, meanwhile, has experimented with ultrasonic jack hammers that would be lighter, quieter, and much more efficient. Ideas like those haven't caught on yet. Instead, electric jackhammers seem to be growing in popularity, largely because they're so much quieter than traditional pneumatic ones.
Artwork: One example of how a hydraulic jackhammer can work. Hydraulic fluid (turquoise, 24) flows in through a nozzle at top left, making a turbine (red, 25) rotate. This spins a transmission (dark green, 7), that powers a crank and connecting rod (dark blue, 12, 6). These move a sliding guide (yellow, 14a) back and forth, allowing a heavy mass (blue, 2a) to strike a rod (green, 15) attached to the tool bit. There's also an ingenious second part to this mechanism. The transmission simultaneously rotates the driveshaft (gray, 13), turning the drill chuck (gray, 16) and making the bit rotate. From US Patent 5,117,923: Hydraulic jackhammer by Wolfgang Wuhrer, Sulzer Brothers Limited, June 2, 1992, courtesy of US Patent and Trademark Office.
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