Three Kingdoms: A Million Soldiers Grown from the Fields

Chapter 192 Beginning
The conversation in front of the craft workshop was just a brief interlude; after a short stay, Zhang Xian went straight to the glue workshop.

The atmosphere in the rubber workshop was busier than usual, with the craftsmen working up a sweat.

Deep inside the building, a research and development area that had been temporarily partitioned off had a particularly somber atmosphere.

After Zhang Xian entered, he took off his brocade robe and wore only an indigo short jacket with the cuffs rolled up to his elbows, revealing his strong forearms.

The huge wooden table in front of him was covered with densely drawn charcoal diagrams.

The drawings were intricate, marked with various dimensions and peculiar symbols; they were the exploded view of the steam engine he had seen through his "future vision."

Old He, Sun Tao, Lu Da, and several of the best blacksmiths, potters, and carpenters in the rubber workshop gathered around the table, their eyes focused yet tinged with a hint of confusion.

They could understand the shape of individual parts, but struggled to comprehend the function of the assembled pile of metal parts.

"My lord, this...this iron belly is so enormous, its inner walls must be as smooth as a mirror, and it must withstand the immense pressure of the 'steam.' Ordinary cast iron would probably be..."

Old He pointed to a cylindrical core component on the blueprint, his brow furrowed.

He had personally cast countless farm tools, weapons, and even waterwheel axles, but this was the first time he had ever made such a precise, sealed cavity.

That's called a cylinder.

Zhang Xian spoke, picked up a sample of gray cast iron that they had previously cast using the new method, and weighed it in his hand.

"This is the key. We need to improve the molding process. The inner mold should be repeatedly polished and baked using the finest clay mixed with graphite powder."

"The temperature and cooling rate of the molten iron during casting must be strictly controlled to avoid sand holes and porosity. After casting, Lao Sun, you and your team need to grind the inner cavity by hand to make it smooth! Tolerance... well, that is, dimensional error, must be controlled within millimeters!"

He gestured with his hand to indicate a very small gap.

"Hiss..." Old He and Sun Tao both gasped at the same time; this requirement was almost demanding.

However, Sun Tao gritted his teeth and agreed.

"Rest assured, my lord, I will risk my life to grind out this 'iron belly' for you!"

"A cylinder! That's called a cylinder!"

"And this piston," Zhang Xian explained again, then pointed to the component that moved up and down inside the cylinder in the drawing.

"It needs to slide perfectly inside the cylinder; it can't be too tight and get stuck, nor too loose and leak air. The piston itself is made of high-quality iron, but the key is the piston rings!"

He picked up a piece of dark black, tough, and elastic vulcanized rubber from the side.

"This thing can now withstand high-temperature steam without softening or deforming. We need to cut it into thin rings and then embed them into the grooves on the top of the piston."

Zhang Xian picked up a wooden piston model and gestured: "The rubber ring expands outward under pressure, tightly adhering to the inner wall of the cylinder to form a seal! This is the key to solving the air leakage problem!"

The successful vulcanization of rubber was the cornerstone of the practical application of steam engines.

Looking at the amazing rubber sheet, Lu Da clicked his tongue in amazement: "My lord, your skill is divine!"

"We can talk about flattery after we've finished this."

Zhang Xian glared at Lu Da.

It then pointed to the connecting rod next to the piston and the huge flywheel.

"The piston moves up and down, driving the crankshaft to rotate via the connecting rod. The crankshaft then drives the flywheel. The flywheel is heavy and stores rotational momentum, which makes the machine run more smoothly and outputs power, just like a waterwheel, except that it no longer needs to rely on the power of water flow."

He used his arm to simulate the action of the connecting rod driving the crankshaft to rotate. As the craftsmen followed his movements, their eyes gradually lit up, as if they had captured a bit of the rhythm of mechanical linkage.

"And this pot..."

A blacksmith in charge of building large containers pointed to the largest part on the blueprints.

That enormous, sealed iron pot with a furnace: "To boil water and produce enough 'steam,' and withstand immense pressure, how thick does the iron shell have to be? What if it explodes…?"

"Good question!" Zhang Xian said solemnly.

"This is of utmost importance, a matter of life and death! The boiler must be repeatedly forged with the best wrought iron to ensure that the texture is uniform and flawless."

In terms of structural design, we need to thicken the steel plates in the furnace and steam accumulation zone, and install a crucial 'safety valve' at the top!

He pointed to an ingenious lever structure on the drawing: "When the steam pressure inside the boiler exceeds the preset limit, this valve will be opened to automatically release steam and prevent an explosion. This valve is related to the safety of the entire workshop and must be absolutely foolproof! Its spring force needs to be repeatedly tested and calibrated!"

"promise!"

The master craftsmen all agreed in unison.

In the days that followed, Jiaofang became the forefront of science and technology in Bingzhou, with lights burning day and night and the sound of hammers never ceasing.

Old He practically lived and worked next to the furnace.

He directed craftsmen to mix the finest river sand with refractory clay and graphite powder, repeatedly pounding, shaping, and baking it to create an incredibly smooth cylinder inner mold.

Each casting is like a ritual, with the temperature of the molten iron strictly controlled using a specially made viewing mirror.

The huge cylinder blanks were slowly cooling in the sand pit, and the craftsmen's hearts were in their throats.

After cooling, they carefully peeled off the outer mold, and Sun Tao then led several of his most meticulous apprentices onto the stage.

They used oil-soaked fine stones and specially made long-handled abrasives to grind the inner wall bit by bit, inch by inch.

The grinding sound continued for several days and nights.

Finally, as his fingers slid across the smooth, cool inner wall, a smile appeared in Sun Tao's bloodshot eyes.

On the other hand, rotating components such as crankshafts, connecting rods, and flywheel shafts have even higher requirements for strength and concentricity.

The craftsmen used a simple lathe powered by a water turbine, which Zhang Xian had invented, along with calipers and squares, to carefully turn and polish the surfaces.

The weight balance of each component was repeatedly checked.

Zhang Xian repeatedly emphasized the concept of tolerance, and the craftsmen went from not understanding it at first to gradually understanding the importance of a perfect fit.

It has been proven that the human hand remains the most sophisticated instrument. Even without the many tools available in later generations, the artisans of this era could still create suitable items with their own hands.

And the accuracy is not bad.

Lu Da then took charge of cutting and installing the rubber parts.

Vulcanized rubber is cut into precise narrow strips and embedded into a groove on the top of the piston to form a highly elastic sealing ring.

He also used rubber sheets to make crucial pipe connection sealing gaskets.

Seeing these elastic, wear-resistant, and heat-resistant black lumps become part of the machine, Lu Da felt incredibly amazed.

Boiler manufacturing is the most material- and labor-intensive process.

The thick wrought iron plate is repeatedly forged and stretched under the power of a hydraulic hammer, and then riveted together by the most skilled blacksmiths.

Although the internal structure of the furnace is not particularly complex, the design of the flue and the maximization of the heating area require repeated consideration.

That small safety valve was personally supervised by Zhang Xian. He dared not be careless in the slightest, from the fulcrum of the lever to the calculation of the counterweight and the fit of the valve.

In mid-June, all the core components were finally placed on the huge assembly platform.

Lao He, Sun Tao, Lu Da, and other core craftsmen stood at the front, holding their breath and focusing intently.

Zhang Xian personally directed the operation. "Put on the base! Align it!"

"Lifting the boiler! Be careful!"

"Cylinder in position! Check the connecting pin with the connecting rod!"

"Flywheel! Slow down, align it with the crankshaft end!"

"Connect the steam inlet pipe and the steam outlet pipe! Make sure the rubber gaskets are tightened!"

The heavy steel components moved slowly and connected with the help of the pulley system.

The hammer gently tapped the locating pin.

Sweat soaked through everyone's clothes.

Each successful docking was met with a suppressed cheer.

As the last component was assembled, a massive, black, complex, and powerful steel behemoth lay silently in the center of the arena.

It is supported by a sturdy iron frame, the boiler is huge and solid, the cylinder stands upright, the flywheel is incredibly heavy, the connecting rod and crankshaft are delicate, and various pipes are connected in a winding manner.

Although the craftsmanship was far from exquisite, with traces of hand forging and rivet marks visible everywhere, everyone present could feel the power it contained.

"Add water! Light the fire!" Zhang Xian's voice trembled slightly.

The apprentices quickly poured clean water into the boiler until the water level reached the preset height.

Inside the furnace, dry firewood was ignited, and then coking coal was quickly added.

Driven by human power, the blower sends a strong airflow into the furnace, and the flames instantly turn from red to white, emitting a whooshing roar as they lick the bottom of the boiler.

Time slipped away in anxious waiting.

The room was completely silent, save for the roar of the fire and the soft gurgling of the water being heated in the boiler.

Everyone's eyes were fixed on the pressure gauge on the boiler.

That was a simple device designed by Zhang Xian, which used a copper pipe to connect to the boiler, with a thermometer with graduations at the end.

This is a technique he derived by working backwards from a thermometer; its manufacturing difficulty is even higher than that of the steam engine in front of him.

The mercury column on the pressure gauge slowly rose.

Old He stared intently at the safety valve, his palms sweating profusely.

Sun Tao repeatedly checked the connection between the cylinder piston and the cylinder.

Lu Da nervously watched the positions of the rubber sealing gaskets.

"Pressure...the pressure is rising!" shouted the apprentice responsible for monitoring the pressure gauge.

The column of mercury was seen rising slowly but steadily.

One mark, two marks... gradually approaching the working pressure scale line preset by Zhang Xian.

suddenly!

"Pfft——!"

The simple slide valve mechanism designed by Zhang Xian at the top of the cylinder, with the intake valve driven by the flywheel shaft via a cam, was suddenly opened by a powerful burst of steam!

A burst of scorching white mist erupted instantly, emitting a sharp hiss!

"It's moving! The connecting rod is moving!" the sharp-eyed craftsman exclaimed in surprise!

Just as steam was injected into the top of the cylinder, the huge piston seemed to be slammed down by an invisible giant fist, moving violently downwards! This, in turn, caused the thick connecting rod to violently pull the crankshaft!

"Boom—click!"
The heavy crankshaft, under immense thrust, emitted a teeth-grinding metallic screeching and creaking sound! This movement seemed to open the floodgates of power! The flywheel's massive inertial rim, driven continuously by the connecting rod, began to overcome the initial friction and gradually accelerated its rotation!
"Woo-hum-hum!"

The deep and powerful roar, like the first awakening roar of a sleeping beast, instantly drowned out all the noise in the rubber factory!

The flywheel spun faster and faster, its heavy body creating a whooshing sound! The crankshaft drove the connecting rod, which in turn pushed the piston, and the piston began a regular and powerful reciprocating motion inside the cylinder!
Under the control of the cam, the steam inlet valve and the steam outlet valve open and close in a precise rhythm, each opening and closing accompanied by a strong steam jet sound and an exhaust sound.

"It's done! It's done!" Old He was so excited that tears streamed down his face, and he knelt down with a thud. He had spent his whole life dealing with fire and iron, and he had never imagined that he would witness such a miracle in his lifetime!

Sun Tao's hands trembled as he stroked the warm, rapidly reciprocating cylinder shell, feeling the surging pulse, and murmured to himself, "It's alive... this iron lump... it's really alive!"

Zhang Xian stood beside the roaring steel behemoth, feeling the slight tremors coming from the ground.

His eyes also shone with excitement, but even more profound was his boundless anticipation for the future.

This crude Unit-01 was the first spark to ignite industry!
"Quiet down!" Zhang Xian raised his hand to suppress the cheers of the crowd, his voice still clear amidst the roar of the machines.

"This 'Unit-01' is just the first step! It proves that the path is correct!"

He walked to the flywheel and pointed to the huge pulley pre-installed on the flywheel shaft: "See this? We're going to use it to transmit power! To replace part of the waterwheel and drive more forging hammers, rollers, and even future spinning and weaving machines!"

"Our lord's wisdom is unparalleled!" the crowd shouted in unison, their eyes burning with unprecedented enthusiasm.

The success of Unit-01 did not stop Zhang Xian from pursuing his goals.

He knew that one prototype was far from enough.

The life of technology lies in its iteration and promotion.

In the days that followed, he continued to work in the morning and conduct research in the afternoon, but he slept for shorter and shorter periods of time.

Together with Lao He, Sun Tao, Lu Da, and other core team members, he devoted himself to intensive improvement and replication work.

In response to the problems exposed by Unit-01, Zhang Xian proposed standardization.

He personally determined the reference dimensions and allowable tolerance ranges for core components such as cylinder bore diameter, piston diameter, connecting rod key interface dimensions, and flywheel shaft diameter.

Subsequent manufactured parts of the same type must conform to this standard to achieve initial interchangeability.

To this end, he also made multiple sets of standard gauges and calipers for the craftsmen to quickly inspect whether the parts were qualified.

This greatly improves the assembly efficiency and maintenance convenience of subsequent machines.

Old He improved the cylinder casting formula, trying to add other metals to cast alloys, in order to improve the strength and toughness of cast iron and reduce brittleness.

Zhang Xian could help with this as well. He had already reverse-engineered the modern items he brought to this era, including many alloy formulas.

However, these are all top secrets, and now that Lao He knows them, he can only accept even tighter protection from now on.

Sun Tao was responsible for improving the tools and methods for grinding the inner bore, resulting in higher efficiency and better precision.

Luda has optimized the shape and installation method of the rubber sealing ring to reduce frictional resistance and improve the sealing life.

While ensuring reliability, Zhang Xian guided the team to begin designing and manufacturing Unit 2 and Unit 3, which had slightly lower power output.

The goal is to improve their versatility and broaden their application to drive equipment with high demands for continuous and stable power, such as rolling mills and large sawmills. At the same time, it is to accumulate experience in miniaturization to lay the foundation for wider applications in the future, such as mine pumping and textiles.

Miniaturization brought new challenges, such as more precise casting of small cylinders and more compact transmission layouts, but it also forced craftsmen to spend one or two hours almost every day listening to Zhang Xian's mechanical courses.

(End of this chapter)