The detachable tube in the Laval nozzle is used to easily change the geometry and length of the expanding part of the nozzle depending on the process requirements. During gas-dynamic spray technology operations, this tube allows precise control of the speed and direction of gas and metal particle flow. This is essential for adapting the process to different materials and coatings, and also extends the nozzle's lifespan, as the replaceable tube can be substituted if it wears out or if a different configuration is needed for specific applications.