Experimental tests and fatigue strength assessment of a scotch yoke valve actuator. (2018)

• Record Type: Journal Article
• Authors: Bergonzoni, M.; Campagnolo, A.; Pellinghelli, D.; Riboli, M.; Spagnoli, A.; Meneghetti, G.
• Is Part Of: Procedia engineering. Volume 213(2018)
• Page Start: 58
• Page End: 68
• Publication Date: 2018
• Subjects: Valve actuator -- structural steel -- Experimental test -- Fatigue assessment -- Strain energy density (SED); Engineering -- Congresses; Engineering -- Periodicals; Engineering; Conference proceedings; Periodicals; 620.005
• DOI: 10.1016/j.proeng.2018.02.007
• Languages: English
• ISSNs: 1877-7058

Abstract

Abstract: Aim of this work is the fatigue assessment of a main component, termed scotch yoke, of a valve actuator used for oil & gas, power and chemical industries, in order to comply with its heavy-duty applications. To do this, full-scale specimens of the scotch yoke made of structural steel have been fatigue tested under nominal axial loading. All specimens have been tested under stress-relieved conditions by adopting a nominal load ratio R=-1. After experimental tests, the fatigue crack paths have been analysed by means of liquid penetrant inspections. The fatigue strength class of the considered scotch yoke has been determined by statistically re-analysing the experimental results, expressed in terms of range of the nominal applied load, and it has been compared with the design condition required by the relevant European Standard, EN 15714-3/4. Finally, two methodologies for fatigue strength assessment of the considered scotch yokes have been proposed, which are based on experimental fatigue data derived from smooth or sharp V-notched specimens, respectively, made of the same yoke material. The assessment capability of the proposed methodologies has been evaluated and discussed by comparing theoretical estimations with the experimental fatigue results of the scotch yokes.