Types segmentation distinguishes the market by mechanical configuration and material construction. Single‑bellows joints, the simplest design, capture approximately 40 % of sales, favored for low‑cost, low‑stress applications. Double‑bellows units, representing about 35 % of the market, provide enhanced flexibility and redundancy for high‑pressure pipelines, especially in power and petrochemical plants. Triple‑bellows assemblies, though niche, hold a 15 % share, employed where extreme axial movement and vibration damping are required. Reinforced or metal‑lined expansion joints, comprising the remaining 10 %, are specialized for aggressive media and high‑temperature environments, often in oil‑field and offshore settings. Each type’s contribution reflects its suitability to specific stress profiles, material compatibility, and lifecycle cost considerations, thereby informing the overall Round Pipe Expansion Joint market taxonomy and influencing investment decisions across sectors.