Chapter 799 - The Bucket Elevator

For security reasons, the Elders' dormitories were located within the integrated machining center compound. Moreover, the machining center equipment still hadn't been touched by any naturalized worker—operating it required at least a high-school-level foundation in mathematics from the old timeline. Grade-B diploma holders were the most qualified workers available, and they simply couldn't manage it.

Zhan Wuya's dormitory was a suite: a small bedroom inside and an outer room that served as a combination living room and workspace—though it functioned more as a conference room. The plant's Elders frequently gathered here to discuss technical issues. In the center stood a large Eight Immortals table surrounded by rattan chairs and long benches. Against one wall was a fitter's workbench with a bench vise mounted on it, and beside it a locked tool cabinet containing his personal tools.

After the six o'clock whistle blew, Zhan Wuya first inspected the fire safety and security situation at the machining center workshop and controlled-materials warehouse, confirming that the power had been cut and all doors and windows were locked. This was daily routine. As Manufacturing Director and General Machinery Plant chief, he held the keys to both facilities and was directly responsible. Zhan Wuya knew the risk of armed destruction here was minimal—the real fear was accidents, especially fire.

Once everything was in order, he instructed his female apprentice to buy late-night snacks and drinks from the Elder's cafeteria for the evening's continued work session. His female apprentice was actually his female servant; Zhan Wuya figured that since he lived at the plant long-term, keeping a servant at home was pointless. Better to have her stay and work as an apprentice. She wasn't cut out for fitter work, but she could manage a lathe.

While waiting for the others to arrive, Zhan Wuya brought several damaged chain links from the workshop to the workbench in the outer room. He switched on the work lamp and examined the broken sections carefully, then studied them for some time with a magnifying glass. He came from a heat-treatment background; though he didn't understand metallography, years of accumulated experience had given him some insight. After studying the fracture for several minutes, his sense was that the problem lay in how the material bore stress.

Before long, everyone had arrived. They examined the fractured links from every angle, discussing how to increase the chain's strength. This time, the General Machinery Plant had been determined to crack the industrial chain problem. Zhan Wuya had personally handled the heat treatment—a large heat-treatment furnace had been specially built for this project. The steel from the Metallurgical Industry Department was the best the steelworks could produce.

But the results were still unsatisfactory. Everyone gathered around the pile of chains, examining them from every angle, occasionally commenting. Liang Xin measured each link with vernier calipers, jotting data on a sheet of paper. Sun Li inspected the chains link by link for any defects. Each person was busy analyzing the chains from their own perspective. Until they'd formed a view, there would be no discussion—hypotheses needed physical evidence.

Zhan Wuya's female apprentice kept their tea topped up and occasionally helped light cigarettes or empty the overflowing ashtray.

By midnight, they had finally reached a unified technical conclusion: uneven stress distribution on the chain. The main cause was manufacturing process issues.

The General Machinery Plant's chain manufacturing process involved forging blanks first, then annealing to relieve stress, followed by machining, normalizing and tempering, surface treatment, and finally assembly.

"I just measured many links," Liang Xin said. "The tolerances aren't ideal—some are as large as ±0.7mm, averaging around ±0.5mm. The dimensional error is too high. According to GB standards, the allowable tolerance for links this size shouldn't exceed ±0.4mm. This shows that the residual stress from machining is more severe than we thought." He continued, "Small tolerance deviations accumulate, causing certain links to bear concentrated stress—and eventually snap."

Sun Li said, "I think we should machine first, then do heat treatment. Even if it wears down some tools, it's worth it—after all, eventually we'll solve the tool problem. They're not one-time consumables that are gone forever once used up. Also, forging should be done at the Arsenal. Their forging press is bigger than ours. For high-strength industrial chain, the more forging tonnage the better."

"Solving the ultra-hard tool manufacturing problem won't happen anytime soon. I'm not sure we can manage it before the end of the First Five-Year Plan," Zhan Wuya said with a frown. Ultra-hard tools required alloy steels—especially tungsten, cobalt, tantalum, and niobium, rare metals whose sources were still unknown. And alloy steel tools demanded high metallurgical and machining capabilities. The Machinery Industry Department relied entirely on old-timeline stockpiles for their ultra-hard cutting tools; Lingao-made carbon steel tools were used only in less demanding work.

After much deliberation, Zhan Wuya said, "That's definitely a factor, but relying entirely on good tools for the lathe won't work. Making chains isn't a one-time job. Until we have verified mass production of qualified ultra-hard tools, I can't rest easy consuming them recklessly. I think we should focus on three aspects: tolerance control, forging, and heat treatment. Do another heat treatment after machining to relieve stress."

The discussion of specific processes and solutions continued until dawn. After eating their late-night meal, everyone dispersed.

The next morning, chain production resumed. After the chain blanks were completed, they were transported to the Bopu Arsenal for forging on its large press—the heaviest-tonnage forging machine the transmigration enterprise possessed. All of the enterprise's large equipment, heavy artillery, and ship keels were forged there.

After forging, the chains were returned to the plant and annealed in the heat-treatment furnace, then machined. But after machining, they underwent another tempering treatment to relieve the stresses introduced during processing. Then they were normalized and surface-treated. Finally, threads were cut, and the links were assembled into seamless chain loops.

"Take it for testing," Zhan Wuya said, looking at the finished section of chain. "Do a tensile test."

"I'll supervise," Sun Li said.

"Good. Be strict! This is our own concern—we're not fooling a customer."

"Of course." Sun Li nodded. "Let's go—to the testing ground!"

Several naturalized technicians who had been observing and learning alongside them answered with a shout, hoisted the chain, and headed out. The female apprentice handed Zhan Wuya a large enamel mug of tea and a towel. He drained most of the mug in one gulp and wiped his sweat. He told the apprentice to bring everyone a few bottles of salted soda water.

"And two packs of cigarettes!"

Several Elders squatted outside the heat-treatment workshop, smoking—no smoking inside the workshop was a rule Zhan Wuya had set. The female apprentice quickly brought over some small stools. Though the naturalized workers had done most of the hands-on work, the Elders had supervised and guided nearly every step, working around the clock for two days and nights. Their eyes were all bloodshot.

Before long, Sun Li returned, beaming. "Holy cow! Success!"

Everyone sprang to their feet. Zhan Wuya was so excited he asked again: "How did the test go?"

"We did a tensile test based on the bucket elevator's actual operating conditions—passed completely. It didn't break until we loaded it to 120%," Sun Li said. "I think we can proceed immediately with a full-machine test!"

"Excellent—once this test passes, compile the process manual right away and start mass production," Zhan Wuya said excitedly. Mining chain was urgently needed—almost every large-scale mining project required it. With the foundation for producing high-strength mining chain, they'd essentially solved the chain problem for many industrial applications.

After the second test succeeded, the General Machinery Plant made further improvements to the bucket elevator. First, they added a ratchet mechanism as an anti-reverse device. The bucket elevator's greatest vulnerability was power interruption. During lifting, one side held buckets full of material going up, while the other held empty buckets going down. If power was cut, gravity would inevitably cause reverse rotation. Material would be dumped back to the bottom of the elevator until it piled up and jammed. Since reversal was an accelerating motion, it could easily tear off buckets and damage equipment.

Modern bucket elevators were all enclosed—to reduce dust dispersal during loading and unloading. To save materials, the Machinery Plant had initially omitted the outer casing from the elevator design. But during testing, everyone agreed it should be installed after all—an iron-sheet casing used minimal materials but dramatically reduced dust pollution. Industrial dust caused occupational diseases that contemporary Lingao medicine was helpless against. Besides, iron ore dust was still iron ore—accumulating little by little, it could be sintered and smelted just the same.

But enclosing the machine introduced new problems. During trial runs, they discovered that sealing caused difficulty loading and unloading the buckets—they wouldn't fill properly or empty completely. They rushed back to the technical archives to find the design drawings. Comparing them revealed that the sheet-metal workshop foreman—a certain Elder—had cut corners by omitting the suction and ventilation openings at the elevator's head and base.

The sealed casing had been expertly made and effectively sealed—but it created a pressure differential during loading and unloading, resulting in negative pressure inside the enclosure and causing blockages. The ventilation opening equalized pressure inside with outside, while the suction opening drew air to prevent dust from escaping through the vent—reducing waste and keeping the environment clean.

"This is a lesson, comrades—a profound lesson," Zhan Wuya said. He couldn't openly reprimand an Elder, but still couldn't resist calling out this case at the work meeting. "Every design feature in industrial equipment, every process method, is the direct embodiment of years of accumulated experience and lessons in industrial society. It's not something anyone can just change on a whim! This kind of careless attitude can lead to serious accidents in industrial production!"

(End of Chapter)