Siheyuan: Starting from the driver

Chapter 780 A Young Calf Breaks Through the Dilemma
Li Kailang had read the information about this machine, but only skimmed through it.

Should I fix it myself now, or should I go through the information again in detail?

Without him asking any further questions, Liu Weiguo immediately instructed the others to return with a large stack of thick files.

"Here you go, Xiao Li, it's all here."

"From the original documents, manuals, and drawings when the equipment was introduced, to the records of each failure, maintenance plans, and expert consultation opinions."

"There are also analysis reports left by experts from the ministry inside. You'd better study them carefully."

He had a "I believe in you" smile on his face.

Li Kailang looked at the pile of documents that almost covered half the table, and said without changing his expression: "Okay, Engineer Liu, I will understand it as soon as possible."

For the next few hours, Li Kailang buried himself in that pile of documents.

I showed everyone how attentively I was reading the materials.

I also took the opportunity to look through all the documents and materials to get a general idea of ​​what was going on.

The dynamic balance was repeatedly adjusted, the bearings were replaced multiple times, the spindle drive motor was inspected, and the meshing accuracy of the transmission gears was tested.
Almost every conceivable mechanical factor was investigated, including the hydraulic and cooling systems.

After gaining a general understanding of the situation, Li Kailang stopped sitting there with his head down.

I got up and stretched my stiff body before going to find Engineer Ling.

"Mr. Ling, I'm planning to go take a look at that machine. Could you give me a certificate?"

Engineer Ling looked at Li Kailang in surprise: "You've finished reading the documents? There's quite a lot of content. Did you understand it all?"

Li Kailang shook his head: "I've gone through it roughly and have a general idea of ​​what it's like. I plan to take a look at the machine first."

“That won’t do.” Engineer Ling shook his head: “This is a treasure of the factory. Let’s wait until you’ve read the documents before we talk about it.”

Although he had previously expressed his support and trust in Li Kailang, the matter involved important machinery, and he could not afford to be careless.

Li Kailang understood, but with so much information, it would take two or three days to read and understand it all, and he didn't know how long it would take to fix it.

He has a cheat code—a repair panel. That's about all the information I've seen; there's not much point in looking any further.

“I understand, but as you know, Engineer Ling, it would take three to five days to review all this information. Besides, you know my capabilities.”

"You know my eyesight and practical skills; you can't figure things out just by looking at the information."

"You've repaired this machine before, and you couldn't fix it, so I couldn't."

Having said that, although Ling was annoyed by Li Kailang's words, he had to admit that what he said was true.

"Okay, I'll take you to see it."

"Okay, thank you for your help."

The atmosphere in the precision machining workshop, where grinding machine No. 3 is located, is completely different from that in the other workshops.

It's quieter here, the ground is cleaner, and the air is filled with the unique smell of a mixture of coolant and metal cutting fluid.

The enormous grinding machine stood silently in a corner of the warehouse. It was not running at the moment, but its majesty as a core piece of precision machining equipment could still be felt.

The machine is located in a warehouse at the back of the workshop, and is surrounded by fences to prevent accidental contact.

The arrival of Engineer Ling and Li Kailang attracted the attention of the workshop director and workers.

"Engineer Ling, what brings you here?" Director Sun came up to greet him.

"Let me take a look at that grinding machine," Ling Hai replied.

Upon hearing this, Director Sun's face lit up with joy.

That grinding machine can only be used occasionally, and I don't know how much pressure it puts on the workshop.

With one less machine working, the tasks naturally fall to the workers.

To ensure accuracy, many workers have to repeat the process three to five times before they can produce a qualified piece.

The two arrived at the grinding machine.

Immediately, the problem with this grinding machine came to mind for Li Kailang.

The grinding machine exhibits abnormal overall accuracy, with fluctuating dimensions of machined parts. This indicates a system-level coupling fault, which conventionally investigated using mechanical, hydraulic, and cooling systems has failed to resolve.

1. Replace the core transmission system assembly (including the spindle drive unit, gearbox, and calibration components).

2. Fabricate replacement and repair of subsystem components (such as custom gear sets or spindle modifications)

Having identified the general problem, the next step is to examine each issue individually to pinpoint its specific location.

At the same time, it's just for show.

Engineer Ling looked at Li Kailang: "Little Li, this is the machine, take a look."

Seeing Li Kailang put on his gloves and about to step over the fence, Director Sun couldn't sit still and tried to stop him, but Engineer Ling stopped him and then gave an explanation.

When Engineer Ling spoke up, Director Sun had to suppress his emotions: "Technician Li, just tell me what kind of cooperation you need, but be careful when operating this machine, it's valuable."

"Thank you, Director Sun. Let me take a look."

After confirming that he was properly equipped, Li Kailang carefully observed the grinding machine.

Instead of taking immediate action, he began to perform the traditional Chinese medicine diagnostic methods of "observation, auscultation, inquiry, and palpation," much like an old Chinese medicine doctor.

Carefully observe the overall structure of the grinding machine, especially the spindle box.

The outer casing has some oil stains, but there are no obvious bumps or deformations.

Notice that at the connection between the spindle box and the bed, there seem to be several fixing bolts with a slightly different paint color than the surrounding area, as if they have been loosened multiple times.

He took out a powerful flashlight and observed the internal structure through the gaps, focusing on the bearing housing and the mounting base of the gearbox.

Approach the spindle box and sniff carefully.

Besides the normal smell of engine oil, there also seemed to be a faint "burnt" smell.

He consulted several experienced operators and asked them in detail about the specific phenomena that occurred when the malfunction happened.

"When the spindle vibrates severely, the entire machine bed shakes, and the surface of the machined workpiece looks like waves, which is unsightly."

"Sometimes it works fine when I turn it on, but then it starts shaking while I'm using it; other times it shakes as soon as I turn it on, but it's fine again after I let it rest for a while and then turn it on again. It's really weird!"

"Furthermore, when the vibration is high, the area near the headstock of the spindle box seems to feel a bit warmer than usual?"

After obtaining permission, Li Kailang carefully touched different parts of the grinding machine with his hands, especially the spindle box housing and the electrical box.

The repair panel works continuously during the observation process, displaying each problem in detail.

Li Kailang nodded in agreement, giving Engineer Ling the impression that he had found the problem.

Through the control panel, Li Kailang also found the cause of the problem that the workers described as sometimes working and sometimes not.

This grinding machine has abnormal friction or stress concentration points, which may be on the support structure of the spindle box rather than the rotating parts of the spindle itself!

Previous repairs may have focused on the spindle, but overlooked potential problems with the support structure.

Li Kailang suddenly felt enlightened.

"How's Xiao Li doing? Have you found any problems?" Engineer Ling asked during his inspection.

“A little.” Li Kailang nodded, then pointed to the bolts with slightly different paint colors at the connection between the spindle box and the bed.

"The bolts securing the base there appear to have been repeatedly disassembled and reassembled. Furthermore, the tightening torque seems inconsistent?"

Ling Hai and Director Sun took a closer look.

Sure enough, the paint around those bolts was badly worn, with varying shades of color, clearly indicating multiple disassemblys. Director Sun slapped his thigh: "Oh dear! Yes, yes! During the previous major overhauls, the spindle box was disassembled and inspected several times, and the bearings were replaced repeatedly. These bolts have definitely been moved! Comrade Li has a sharp eye!"

His gaze toward Li Kailang held a newfound trust.

On the contrary, Engineer Ling frowned slightly. He remembered that after each disassembly, he was required to reassemble it according to the standard torque.

However, since the specific operation is carried out by the maintenance team, are there any minor deviations?

He looked at Li Kailang: "You suspect it's installation stress?"

“Not entirely,” Li Kailang shook his head; he needed to translate the prompts on the repair panel into logical reasoning.

"Installation stress may cause localized deformation."

The well-reasoned explanation convinced Engineer Ling, who nodded in agreement.

This also explains why replacing the bearings and adjusting the dynamic balance were ineffective before – if the foundation is unstable, adjusting it on top is futile.

That wasn't all. Li Kailang walked to the vicinity of the spindle drive motor and pointed to the electrical control cabinet.

"Is there a delay or distortion in the load feedback? This could cause unstable motor output, especially during startup and speed change."

He also took the opportunity to bring up some content from the documents.

“This,” Ling Hai recalled, “experts in the department mentioned the problem of the aging drive unit, but the test results were within the acceptable range, and the replacement cost was too high, so we haven’t touched it.”

After a series of questions, Li Kailang completely dispelled the distrust and doubts of Engineer Ling and Director Sun.

"Xiao Li, I knew I hadn't misjudged you. I'm impressed by your judgment!" Engineer Ling had no choice but to admit defeat.

"What are you going to do next?"

This is of utmost importance.

Li Kailang, meeting the expectant gazes of Engineer Ling and Director Sun, had already made his plans in mind.

This grinding machine is far more complex than ordinary equipment; it's not something someone fresh out of school could easily repair.

However, he must carefully conceal the secret of possessing the [Repair Panel].

It would be satisfying to directly point out the core problem and fix it quickly.

But that would be too shocking and inconsistent with his persona of being "skilled but still within reasonable limits," and might even attract unnecessary scrutiny.

“Engineer Ling, Director Sun,” Li Kailang said, his face showing a serious expression as he faced a difficult problem.

"The problem is indeed quite tricky, and adjusting a single aspect is unlikely to solve it completely, just as I just mentioned."

"The safest way to completely solve this problem is indeed to replace the core transmission system assembly, including... but these are too costly and would have too much impact on the factory's production."

Engineer Ling and Director Sun nodded in unison; this was precisely what troubled them the most.

Experts in the ministry also mentioned this plan, but no one chose it, since replacing one set would require too much foreign exchange.

“Therefore,” Li Kailang changed the subject, “I suggest using subsystem components for replacement and repair.”

"I'm trying to see if I can make a higher precision gear set to replace the old gear set on the grinding machine, so that it will have less impact on the grinding machine."

"The other parts are replaced in a similar way, little by little."

This plan is clearly more in line with the actual situation of the factory.

"Can you make it?" Director Sun was somewhat skeptical of Li Kailang, wondering if a greenhorn could make a high-precision gear set.

But then he added, "Our factory has precision machining capabilities, as long as you can provide the drawings and parameters."

“We have the blueprints and parameters,” Engineer Ling said. “You don’t need to do it; just let the factory’s level eight technicians do it.”

Although he had confidence in Li Kailang's hands-on skills, it was still a high-precision workpiece, so he decided to have an eighth-level worker from the factory do it.

As for Li Kailang's plan, he and the experts in the department had also considered it and even tried it.

However, he was far less decisive than Li Kailang, who immediately replaced the entire set of clothes!

They replaced each small part one by one, afraid to use large parts, lest the whole thing break if they replaced the wrong one.

I can't take that responsibility!!!

"They're really fearless like newborn calves!" Engineer Ling couldn't help but exclaim.

Young people are great; they don't worry about the consequences and just go for it!
Li Kailang didn't understand Ling Gong's ambiguous words, but he still explained his plan in detail.

"Mr. Ling, you are very experienced. Do you think this plan is feasible? My initial estimate is that it may take three to five days just to manufacture the gear set."

"Including testing and adjustments, as well as subsequent installation, debugging, and accuracy verification, it may take ten days to half a month to see the initial results."

"During this period, the close cooperation of the workshop workers is also needed."

Li Kailang deliberately prolonged the timeframe to conceal his shortcomings and the fact that he had already seen through the essence of the problem.

During this period, he needs to "discover" and "solve" the problems step by step, ultimately leading to the answer already provided by the repair panel.

"Good!" Engineer Ling patted Li Kailang's shoulder hard, a smile of approval on his face.

"Xiao Li, your thinking is very clear, and your plan is feasible! Let's do it your way! Just let us know if you need any resources!"

"Director Sun, please cooperate fully with Xiao Li. Priority will be given to ensuring manpower and equipment in the workshop! If there is any other need, I will also arrange for other workshops to cooperate."

Director Sun quickly replied, "No problem! Technician Li, just let me know if you need anything! I'll have Xiao Wang assist you!"

Repairing this grinding machine was a great help not only to him but also to the workshop.

"Thank you, Engineer Ling! Thank you, Director Sun!"

With a firm resolve, Li Kailang successfully took the first step of his plan.

the following few days.

Li Kailang's work pace has accelerated.

With blueprints and parameters, the fitter workshop can start manufacturing the parts directly.

Instead of immediately starting his "performance-style" repairs, he plunged back into the documents and files.

In particular, the analysis reports left by the experts from the ministry and the detailed records of each maintenance.

He needs to lay a sufficient knowledge foundation for his "discovery" process.

After laying the groundwork, we carefully studied the original drawings from when the grinding machine was introduced, especially the design drawings and material specifications of the spindle box support structure.

By comparing the data from previous repairs, we can identify potential correlations among the various components.

To outsiders, this work appears to be Li Kailang thoroughly understanding the materials and laying the foundation for subsequent work.

In reality, he was using the precise directions provided by the repair panel to reverse-engineer theoretical basis and a "reasonable" entry point.

He was exceptionally focused, often spending half a day in the archives, his notebooks filled with analyses, questions, and speculative sketches.

This dedicated attitude made Engineer Ling, who occasionally came to check on the progress, even more satisfied.

This is the problem that's giving him the biggest headache.

He's not an engineer; he has to deduce the reasonable steps and conclusions one by one.

If he were an engineer, he might just give a quick explanation, or even no explanation at all.

Let everyone guess!

They're impressive if they can guess it!
If you can't guess it, then Li Kailang is really amazing!
(End of this chapter)