Tubesheet strength calculation is important work in design of heat exchangers.The thickness of the tubesheet depends on the two major factors: loads and structure.The former includes fluid pressure and metal thermal gradient.The later involves tubes bundle located at inner perforated area of tubesheet and constraints applied by flanges or shells at the outer ring of tubesheet.As an elastic foundation,tubes bundle is one of critical factors in calculation of tubesheet system The effect and current problems of tubes bundle support is reviewed in this paper.Analysis and experiments show that current single tube buckling criterion used in the strength design of the tubesheet may lead to an inaccurate calculation of the tubesheet thickness since this criterion is conservative for a long tube or aggressive for a short tube.A more reasonable and safe criterion for considering the tube bundle support is proposed in this paper which could make the tubesheet thinner and thus,decrease the cost of the heat exchangers.In addition,the idea proposed in this paper may be helpful to develop a new standard for the strength design ofthe tubesheet or even the tubesheet system.
展开▼
