Doomsday: Humanity shrinks 100 times

Chapter 75 Difficulties abound
"Valve. Are you talking about the airtightness problem?" Lu Yuning pondered.

Zhang Xinyue nodded. "Well, this device requires valves to control the intake and exhaust of air. There are quite a few valves, and if they are not handled properly under high pressure, there will be leakage problems."

Lu Yuning thought about it for a long time. He had never thought about the problem of this valve before, but he could not be careless with this kind of pneumatic device.

"Or why not just do without the valve and use Yu Ning's special ability directly?" Wu Xiao suddenly had an idea.

".This..." Zhang Xinyue's eyes lit up and she looked at Lu Yuning.

Lu Yuning shook his head: "You may have misunderstood. My ability is to crush and reassemble. It is to combine existing materials into new shapes."

Everyone was confused.

"For example, I can crush two pieces of plastic at the same time and then combine them into one piece, but I can't directly fuse them together like glue," Lu Yuning explained.

"So that's how it is." Wu Xiao understood.

Zhang Xinyue also felt a little regretful, and then said, "Well, it seems there is no good solution. We can only try to make the brake part of the valve smoother."

"Smoother?"

"Well, actually, the valve is subject to high pressure in the system, and the internal obstruction will stick to the pipe wall. The greater the pressure, the tighter it sticks. So the final cause of the leakage is actually the irregular contact surface."

"If that's the case, can that piece of rosin be used to apply a layer of rosin on the blockage?" Lu Yuning suddenly thought of the rosin he had brought back before.

Zhang Xinyue was stunned: "Rosin?"

"Well, I forgot to mention it before. This time, I not only brought back a lot of food, but also some pine resin. I wonder if this thing can be used." Lu Yuning explained.

Lu Yuning hadn't had time to tell Zhang Xinyue about the small piece of pine resin he brought back from the forest, so Zhang Xinyue naturally didn't know about it.

Zhang Xinyue's eyes lit up: "Perhaps, if the joints are made more precise and filled with rosin, it can ensure airtightness to a certain extent."

Lu Yuning nodded.

In this way, the problem of valve air tightness has been solved. Of course, the specific effect still needs to be tested.

All the difficulties they are facing now are actually caused by insufficient productivity, and in the end they can only think of some roundabout solutions.

"As for the cooling efficiency issue, I think there is really no good solution at the moment. We can only wait and see." Zhang Xinyue thought hard for a long time and finally spoke helplessly.

"Can we try asking Sister Qian to isolate the boiling water?"

"Yeah, that's possible, but it probably won't be very effective. The heat dissipation of the container mainly depends on the heat difference between the inside and the outside. But after we pump back the first bucket of water, we can consider using the excess water to build a cooling system."

Lu Yuning nodded. "That's about it. We can't use plastic as the material, right? I guess we have to use the high-density material like the ones used in trash cans. But I have another question: will this material produce toxic substances when exposed to high temperatures?"

Common plastic materials have poor temperature resistance. When the temperature reaches a certain level, they will deform and release toxic substances. That's why Lu Yuning had this question.

"No, in fact, the materials of trash cans are also different. Some are made of polypropylene and some are high-density polyethylene. However, both materials have relatively high melting points. At 100 degrees, there is no need to worry about the production of toxic chemicals."

Lu Yuning nodded and felt relieved.

"Well, it looks like I have to make another trip to the garbage station."

It was still early, so Lu Yuning prepared to pack up and go collect materials.

This device probably won't be completed so quickly, so he thinks it's better to put it into practice sooner rather than later so that he can find solutions if there are any problems.

There were no accidents on this trip.

Since Lu Yuning's abilities have been greatly improved, the collection of materials was much faster this time.

In addition, Zou Yunxin was brought over this time, which increased the labor force.

Lu Yuning directly enlarged the hole in the trash can, and the three of them worked together to drag out a mineral water bottle from it. Then they directly converted the mineral water bottle into a simple four-wheeled cart.

Although the workmanship is rough and it is difficult to control the direction due to its wobbling motion, there is no need to worry, just push it back slowly.

Finally, I stuffed all the materials taken from the trash can and the plastic materials from mineral water bottles into it.

When the three of them returned to the shelter, they were already exhausted and out of breath.

Lu Yuning was already thinking halfway through that he had to find a better means of transportation when he had time.

This time I brought back almost three mineral water bottles and a bunch of trash can shell materials.

The material problem has been completely solved.

It was getting dark, but Lu Yuning didn't want to waste time and immediately prepared to start work.

"So what's the first step?"

Although the steam water pump project officially started, Lu Yuning was stumped when it came to the actual implementation. He looked at the design drawing in front of him and had no idea where to start.

"As you said before, your ability is only to crush and reassemble, not to fuse. Then you need to directly make the framework, including the boiler, vacuum container, and pipeline, and then reserve the valve setting points." Zhang Xinyue said.

"Can we get it all done in one go?" Lu Yuning was not sure.

"This is the only way at the moment. If we want to make individual components and then combine them, we may need to make a threaded structure to ensure the sealing," she explained.

Zhang Xinyue suddenly thought of something and reminded him, "Oh, by the way, we don't need two vacuum containers. We can just make one. Wouldn't that be simpler?"

"Are you talking about these two containers next to the boiler?" Lu Yuning pointed to the design drawings on the ground.

"Well, we used two vacuum containers at the beginning of the design. The main consideration was that alternating cooling would be more efficient. We haven't yet touched on the efficiency issue." After Zhang Xinyue finished speaking, she revised the design drawing in front of her and removed one vacuum container.

The whole system looks much simpler.

Lu Yuning looked at it for a while, then asked, "Okay, let me try it out. What is the volume of this boiler and vacuum container? And what is the diameter of the pipe?"

The two discussed for a while, and finally Lu Yuning had a clear understanding of what they were going to do.

The boiler container used to hold water does not need to be too large, as long as it can hold enough water.

Vacuum containers are a bit more particular, and the diameter and length of the pipe, as well as the horizontal height, must be considered.

Since there is a height difference between the river water and the container, the gravity of the water must also be considered.

In short, if it is made too small, the water will not be absorbed into the container; if it is too large, the cooling efficiency will be too low and materials will be wasted, which will increase the difficulty of Lu Yuning's production.

Lu Yuning didn't understand this part at all, so Zhang Xinyue had to worry about it.

Zhang Xinyue wrote and drew on the ground for some time, and finally breathed a sigh of relief, as if she had finalized the plan.

She said to Lu Yuning, "That's it. The steam oven only needs 20 ml. The vacuum container should be slightly larger, 150 ml. They should be round so they can withstand greater pressure. The inner diameter of the pipe should be 2 mm first to see if it will get clogged."

"2 mm? How big is it?" Lu Yuning was suddenly confused.

Zhang Xinyue was also stunned, and a new problem arose.

How to determine size.

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(End of this chapter)