Research On The Assembly Pattern And Leakage Of Bolted Flange Joint With Metal-to-Metal Contact Type

In order to ensure safe operation of the device in long period, bolted flange connection system increasingly high requirements with modern process plant is increasingly used in extreme environments such as high temperature and high pressure operation.Bolted flange joint (BFJ) with metal-to-metal contact type (MMC) have a more broad application prospects in these working conditions. Compared with traditional BFJ with floating (FLT), the sealing surface of BFJ with MMC have a constant pressure, could withstand higher bolt preload, it have a stable sealing performance when the device operating parameters fluctuations. However, the study of assembly pattern of BFJ with MMC is still few, and it’s still no mature assembly pattern. Therefore, it is necessary to have a study on assembly pattern witch impact the sealing performance of BFJ with MMC.Combines the structural features and sealing principle of BFJ with MMC, this paper recommend a assembly pattern for BFJ with MMC. Concentrate on the assembly pattern, this paper combine the Star assembly pattern and Alternative assembly pattern#3witch ASME PCC-1proposed, taking an example of the DN80flange, this paper performed the ANSYS FEA simulation studies, and compared with BFJ with FLT. The results show that BFJ with MMC tightening result is better, faster, compared with BFJ with FLT under the same assembly pattern, and the recommend method is better than other assembly pattern in preload effect.Also, this paper build the strength and sealing flange joint bolts DN80of performance testing device, the changes of bolt force when tightened and the affect of sealing performance of BFT in different assembly pattern were studied experimentally, the laboratory studies show that, the recommend assembly pattern of BFJ with MMC is more saving time and effort, and the BFJ with MMC have a better sealing effect compared with other assembly pattern.