The secret behind China's 'explosive carving' craft

Xu Liping, a technician at the 7416 factory of the China Aerospace Science and Technology Corporation, has spent more than three decades in this special profession, becoming a symbol of courage and dedication.

Dangerous job: "Explosive carving"

Solid fuel, an important component of rocket engines, plays a decisive role in the trajectory and accuracy of rockets. However, to ensure the fuel surface meets standards, technicians must use special knives to adjust every small detail. This job is likened to "working in a pile of explosives" because even a small mistake, such as the knife touching the metal shell or creating too much friction causing static discharge, can lead to an explosion.

Tu Lap Binh , who is known as the "explosive carving artist" , started this job in 1987 when he was only 19 years old. He recalled that at first, it was only because of his mother's advice that he joined the workshop where she used to work. But the first experiences left a deep impression on him, making him determined to practice his skills to perfection to minimize the danger.

Solid fuel is an essential component of many types of rocket engines, especially ballistic missiles. It is a special mixture, including fuel and oxidizer, tightly combined together in a solid mass.

Engine Surface Forming Expert

Fuel surface shaping work requires not only absolute precision but also sensitivity and many years of experience. In fact, solid fuels are not uniform in structure, they contain many coarse particles, making cutting and smoothing the surface extremely difficult. Just a cut that is too deep or leaves a knife mark, the fuel may not burn in the intended direction, damaging the engine or even leading to an explosion.

During his 30 years in this job, Tu Lap Binh has constantly trained. He developed techniques such as cutting and trimming with high precision, and created a series of specialized tools. With each operation, with just a touch of his hand, he can determine the accuracy needed for the fuel to meet the design. The products he edits always achieve a 100% standard rate.

Not only stopping at manual skills, Tu Lap Binh also researched and improved working tools, helping to reduce risks and increase labor efficiency. He designed and registered many national patents in China, including products that are affectionately called "Dao Lap Binh" by his colleagues.

To create the perfect solid fuel surface, Xu Liping must use hand tools and work under extreme pressure. A small mistake in this process can have serious consequences, from damaging the engine to triggering unwanted explosive reactions.

Face the danger to innovate

Although technical advances such as CNC technology have helped in some ways, many important steps still require human hands. Tu Lap Binh not only participates in the operation but also contributes to improving the machine, suggesting more than 20 technical changes to make the equipment more suitable for production requirements.

Success in applying technology has contributed to increased work efficiency, but for Tu Lap Binh, ensuring safety is still the top priority. Once, during the development of the main engine, two consecutive tests failed, forcing the research team to dig the fuel directly out of the engine to find the cause.

The process was extremely dangerous, as the team of technicians had to work in a confined space, surrounded by tons of explosives and a strong chemical smell. Each person could only endure a maximum of 10 minutes inside. But Tu Lap Binh, although the youngest member of the team, volunteered to work longer to support his colleagues.

The profession of 'explosive carving' is not just a job, but also a lesson in courage, dedication and responsibility. It is an inspiration for all generations, not only in China but all over the world.

For more than three decades, Xu Liping has been not only a technician but also an innovator, a pioneer who always seeks to innovate and improve production processes. He has made important contributions to enhancing China's technological self-sufficiency, especially in the field of solid rocket engine production.

Solid fuels are one of the core components of rocket engines, characterized by their stability, ease of use, and long-term storage. The main components of solid fuels include an oxidizer, a fuel, and a binder. The oxidizer, such as ammonium perchlorate (AP) or potassium nitrate (KNO₃), provides oxygen to sustain combustion in an anoxic environment, while the fuel, usually a metal powder such as aluminum (Al), generates a large amount of heat energy. The binder not only helps these components bond tightly but also acts as an additional combustible material, with common materials being polyurethane or hydroxylated polybutadiene (HTPB).