Restoration technologies for precision diesel injector components using vacuum chromotitanizing and grinding
Year: 2025
Type: article
Abstract: This study comprehensively explores the wear mechanisms, restoration techniques, and precision mechanical processing methods applied to diesel engine injector needles, which play a critical role in ensuring accurate fuel atomization and efficient combustion in internal combustion engines. Subjected to extreme operational environments, these injector needles are prone to multiple forms of degradation, including abrasive, corrosive, thermal, mechanical, cavitation, and fatigue-related wear. The deterioration of the injector needle and the sprayer body directly affects fuel delivery efficiency and engine performance, often leading to increased emissions and fuel consumption. To address these challenges, the study proposes a restoration methodology that integrates vapor-phase diffusion chromotitanization – a thermochemical surface treatment that enhances hardness and wear resistance – with high-precision mechanical reprocessing. Specifically, the restored injector needles undergo grinding using synthetic diamond wheels of the AC6-100/80 MB1 type at 100% diamond concentration. Experimental optimization determined the ideal transverse feed to be 0.42 mm/min with a driving wheel speed of 50 min⁻¹. Following grinding, a multilayer finishing process is carried out using cast iron lapping tools and KT-based abrasive pastes to refine the surface texture. The resulting surface roughness values achieved were within Ra = 0.032–0.040 μm, and geometric deviations remained under 1 μm, matching or surpassing factory-level precision standards. The findings confirm that the proposed restoration process not only extends the operational life of injector needles but also supports sustainable engineering by reducing the need for complete part replacement. This contributes significantly to resource conservation and environmentally responsible maintenance practices in diesel engine technology. Keywords: needle; spray body; nozzle; chrome-titanium plating.
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W7124444461