2.2. Impact on Hammer Design

So, basically what to do here is, so this is a setup of the double acting steam hammer, you can see two cylinders one is the upper cylinder, other one is a lowest cylinder. Now in the upward stroke what you do is, you supply air into the lower cylinder. So, when you supply into this, this is the lowest cylinder, when you supply air into the lower cylinder, the hammer which was earlier in the lower cylinder will be pushed up into the upper cylinder.

In a double acting steam hammer, there are two cylinders, known as the upper and lower cylinders. When someone operates the hammer, they start by supplying air into the lower cylinder. This influx of air causes the hammer that was resting in the lower cylinder to be pushed upwards into the upper cylinder. This is the first part of the hammer's movement, known as the upward stroke.

Think of this mechanism like a balloon. When you blow air into the balloon, the air pressure pushes the walls of the balloon outwards. Similarly, here, the air is pushing the hammer upwards just like the air in a balloon expands.

So, the hammer is pushed up into the upper cylinder, the air which was already there in the upper cylinder will expel out to the exhaust. So, basically what you are doing here is you supply air into the lower cylinder. So, that will push your hammer upward into the upper cylinder and the air which is already in the upper cylinder will be released through the exhaust, now your upward stroke is complete.

After the hammer moves up into the upper cylinder, the air that was already contained in that cylinder needs to go somewhere. Therefore, as the hammer rises, it forces that air to exit through an exhaust. This process completes the upward stroke of the hammer, readying it for the next downward movement.

Imagine a filled syringe. When you push the plunger down, the fluid inside the syringe is forced out of the needle. Here, the hammer's movement works similarly—it pushes air out as it moves up.

So, what are you doing the downward cylinder? You supply air through the inlet into the upper cylinder. So, when you are supply air into the upper cylinder, the hammer which was already there will be pushed into the lower cylinder. And air which was already in the lower cylinder will be expelled out through the exhaust. So, now that completes a downward stroke, so alternatively you are supplying air into a upper cylinder and the lower cylinder, so that you can have the rising and falling.

To initiate the downward stroke, air is supplied into the upper cylinder instead. This causes the hammer, previously in the upper cylinder, to be pushed downward into the lower cylinder. Concurrently, the air that was previously in the lower cylinder is expelled through an exhaust, completing the downward motion.

Consider a seesaw in a park. When one side goes up, the other side must go down. In this scenario, supplying air to one cylinder makes the hammer rise while the opposite action inverts its position.

Another important thing we need to know with respect to double acting hammer is in this most of the blow energy is derived from the steam energy. Both for the upward stroke as well as for the downward stroke, the blow energy is derived mainly from the steam energy. So, 90% of the blow energy is derived from the action of air or the steam.

In double acting hammers, a significant amount of energy needed for the hammer to strike downwards is sourced from steam energy. This steam energy accounts for about 90% of the blow energy generated during both the upward and downward movements of the hammer. This is a crucial component in understanding how the hammer is designed and operated.

You're using a kettle to boil water. The steam produced when the water heats up could be likened to how the steam provides energy to the hammer. Just like steam can create pressure, the steam in this case pushes the hammer up and down.

So, that is why, for the double acting hammer we need not for a heavier hammer. We can go for lighter hammers, smaller in size and you can go for the shorter stroke or shorter height of fall. So, these hammers are basically designed to be lighter in weight.

Because most of the energy required for the hammer's working comes from steam, there's no need for the hammer itself to be excessively heavy. This allows designers to create lighter and smaller hammers, in turn making the mechanism more efficient and easier to handle.

Think about a toy hammer. It's made of plastic rather than metal, yet it can still hammer nails in because it's designed for that purpose. Just like the toy hammer, a double acting steam hammer doesn’t need to be heavy because of how effectively it uses steam energy.

And this hammer is basically designed for lighter conditions, lighter conditions in the sense. So, it is basically designed for light to medium weight piles and for soil with normal frictional resistance.

The design of the double acting hammer is tailored for lighter applications. This means it works best with light to medium weight piles and on soil types that have a normal level of frictional resistance, making it unsuitable for very hard or dense soil conditions.

Consider a light bicycle. It’s perfect for smooth roads, but when you enter rough terrain or mud, it struggles. Similarly, the double acting hammer excels in softer soil conditions but isn't effective in harsh environments.

So, very tight clay, hardened clay with very high frictional resistance, so we are not supposed to use these double acting hammers. Because these double acting hammers are designed for lighter conditions, that means for light to medium weight piles and for the normal soil with normal frictional resistance.

Double acting hammers are not designed to work with extremely tight or hard soil conditions, such as hardened clay. Their operational efficiency drops significantly in these conditions due to their high blow rate, which can actually damage materials like concrete.

Imagine trying to use a delicate tool in a very tough material. It’s likely to break or fail. Similar to that scenario, using a double acting hammer in tough clay can lead to damage.

So, to summarize what we discussed, so your use of steam energy in driving the ram allows use of shorter stroke and compact hammer than single acting hammer.

To summarize, double acting steam hammers are compact and efficient thanks to their use of steam energy. This method means shorter strokes are viable compared to single acting hammers, as there is sufficient energy derived from the steam to drive the hammer effectively.

Think about how compact and efficient modern appliances are compared to older models. The evolution over time mirrors how double acting hammers have improved, employing steam for a more effective design.

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