NEW JCM Craftsman｜Lyu Dongrui: Engraving Rigor into Every Assembly Procedure

"Either don't do it, or if you do it, do it right—never leave a job half-done."

"Click, click..."
The torque wrench seats firmly onto the nut. Lyu Dongrui, a compressor fitter at Jinzhou NEWJCM Machinery Manufacture Co.,Ltd., leans forward, his shoulder dipping slightly as he re-applies force to the split-line bolts he has just tightened. Crisp ratcheting sounds ring out, accompanied by the solid resistance feedback from the wrench.

"After torquing a full circle of bolts to spec, you have to go back and recheck every single one. If the resistance is even slightly off, it could lead to bolt fatigue or gas leakage out in the field."

As the "heart of industry," a compressor tolerates not the slightest assembly error. In Lyu Dongrui's eyes, there is no shortcut to keeping this "heart" beating smoothly—only extreme rigor and a deep reverence for quality.

1.Rigor First—Data Is the Only Yardstick

In compressor assembly and overhaul, clearance and tolerance requirements are extremely demanding. If clearances are too tight, rotor rubbing can cause severe vibration or even burnout; if too loose, equipment efficiency may plummet. Working with micron-level precision year after year, experience and feel certainly matter—but in Lyu Dongrui's mind, drawings and specifications are red lines that must never be crossed.

"Never take a gamble based on personal experience," Lyu Dongrui says firmly. "Any deviation outside the technical requirements—even if it feels 'close enough to work'—must never be let through. Equipment is expected to run continuously in the field for years or even decades. A tiny oversight during assembly can snowball into a major problem down the road."

"I'd rather spend the extra time rechecking three or four times than let a single hidden risk leave my workstation." Driven by this rigorous mindset, Lyu Dongrui has safeguarded the smooth operation of every piece of equipment that has passed through his hands for thirteen years.  

2.Extreme Confined Conditions, 48 Hours of Hardcore Troubleshooting

With his solid skills and strong sense of responsibility, Lyu Dongrui is both the steadying anchor on the shop floor and the frontline troubleshooter when urgent, difficult, or high-stakes problems arise at project sites.

On one occasion at a project site in Inner Mongolia, a unit suddenly broke down, bringing the entire production line to a halt. After receiving the call, Lyu Dongrui and his colleagues packed their toolboxes overnight, traveled by sleeper train and long-distance bus, and arrived at the remote site—dusty and weary—well past midnight.

Conditions on site were far trickier than expected: with limited environmental resources, no heavy crane could be brought in, and the unit was surrounded by a dense network of piping. The working space was so cramped there was barely room to swing a hammer. Under such conditions, performing micron-level alignment and centering on a massive compressor casing was daunting to say the least.

"When conditions aren't there, you fall back on the simplest methods and grind it out bit by bit."

Without a crane, Lyu Dongrui relied on the threaded jacking screws on the equipment's support legs, turning them by hand turn after turn to lift the multi-ton steel casing inch by inch, then slipping shims underneath. With no room to stand, he worked bent over, wedged into the gaps between pipes.

To meet the stringent alignment tolerances, he took readings with a dial indicator again and again, calculating shim adjustments while crouching for four to five hours at a stretch, going through four full rounds of fine-tuning. After 48 straight hours of working through the night, even with his back aching and body exhausted, his hands remained rock-steady as he verified data and operated instruments. When all parameters—concentricity, levelness, and more—came in on spec, the unit roared back to life and started up successfully in a single attempt!

This calm technical confidence extends overseas as well. During a unit overhaul project in Malaysia, complicated site conditions and differing interpretations of the drawings among foreign personnel brought bearing removal to a standstill. Drawing on his deep familiarity with similar equipment structures, Lyu Dongrui correctly identified a hidden locking mechanism inside the bearing and patiently guided the disassembly on site, earning sincere praise from the foreign engineers. 

3.Ingenuity Boosts Efficiency—Breakthroughs Come from Engagement

Working day after day with cold steel and repeating the same motions, a fitter's job may seem monotonous to outsiders. But in Lyu Dongrui's view, while procedures may be fixed, one's thinking never has to be.

"Every compressor handles a different medium, so internal structures vary. In this trade, there's always something new to learn," Lyu Dongrui says with a smile. "Even when doing the same task, if you put your mind to it, one day you'll suddenly realize: try a different approach and you not only save time—you can double your efficiency."

In the traditional concentricity assembly of compressor end covers, diaphragms, and rotors, the old rule was a "two-step" approach: first take preliminary concentricity readings with a dial indicator, then install the bearings and recheck. But Lyu Dongrui noticed that the initial "pre-reading" step was not only laborious—once the bearings were installed, the data often no longer matched.

"Since the real operating condition is with the bearings installed, why not install the bearings first and work backward to find the center?"

He acts on his ideas, but never recklessly. He strictly adheres to process discipline: "A new method has to be discussed with the inspectors and technical leadership. We compare the old and new measured data repeatedly, confirm that accuracy is fully on spec, and only when everyone signs off does it get approved. It's not about doing whatever I want."

After rigorous testing and data validation across multiple units, this new "direct bearing installation verification" procedure proved not only more intuitive and more accurate, but also significantly shortened assembly cycles. Today, this "small innovation" born on the front line has been formally incorporated into the factory's standard operating manual and rolled out across the entire workshop.

Lyu Dongrui often says: "Either don't do it, or if you do it, do it right—never leave a job half-done."

This plain-spoken maxim, rooted in the front line, embodies the reassuring confidence of a NEWJCM craftsman. From every rise and fall of the wrench in daily assembly to overnight emergency repairs in faraway places, he has written his reverence for tolerances into every minuscule clearance. This relentless pursuit of perfection hidden within each procedure is the very essence of NEW JCM's commitment to excellence!