Sivasankaran Leaky Reformer tubes : The only way to stop leaks is to do hot crimping at both inelt and outlet pigtail tube ends of the leaky reformer tube when in service. Crimping procedure (pressure to be applied for crimping and type of holders / fixtures to secure at the location of crimping (to be used for crimping) depends on the make and type of fixtures supplied by crimping tool suppliers. ICI crimping tool procedure will be different from that of another crimping tool procedure. You have to use high pressure crimping fixtures with even high temperature withstanding studs / bolts . Crimping tool should be designed with high temperature metallurgy ( SS for inlet tubes / Incoloy 800 H for outlet pigtail). Pressure to be applied for crimping depends on the hydraulic jack /fixtures supplied by the crimp tool supplier. If you have procured a crimp tool from a supplier, follow his crimp tool instructions / tools / fixtures. In spite of good crimping procedure, possibility of some leaks at the crimped locations may occur in some cases. In such a case, you may have to do a second crimping before the pigtail gets cold at 90 degrees to the first crimping if there is space in the straight leg of both inlet and outlet pigtails. Some users use a second crimping as a back up against failure of first crimped locations after crimping as a safe practice to ensure that reformer tube leak is contained. This depends on the safety considerations the plant would like to adopt. You should remember that you cannot do crimping when intet or outlet tubes become cold. Cold temp crimping is not advisable for these used materials. If leak persists, inspite of two crimping attempts, you have no other go than to shut down the reformer furnace. Hope this helps C.V.Srinivasan Nishi Engineers Pvt Ltd India Sept 26, 2010 E-mail: nishi@vsnl.com >Dear Experts, > >Could you please share the experience in plugging the leaky >reformer tubes with a brief procedure? Whether to use a >tapered plug or forged caps at both inlet and outlet pigtail >connection ? > >Thanks in advance > >S.Sivasankaran

Sivasankaran In cold condition: Dummying inlet tube flange end with blanks both at the inlet header end and at the reformer tube inlet entry end would not allow any gas entry. However the leaky reformer tube, which had been blanked from gas entry at the inlet tube end and with capped outlet pigtail tube at the outlet header end, may warp or distort due to no gas flow if there is flame impingement due to burner configuration changes inside the furnace. For the outlet pigtail you may have to provide a solid forged Incoloy 800 H cap (either taper plug cap or even full solid cap to suit ID and strength weld at the outlet header to outlet pigtail tube to prevent gas back up from header end to outlet pigtail tube. Hope this helps C.V.Srinivasan Nishi Engineers Pvt Ltd Sept 29, 2010 E mail :nisihi@vsnl.com >Sir, >Thank you very much for sharing your experince. > >Suppose if we take shutdown of the reformer for attending >the leak, is it better to use plug or cap instead of >crimping in hot condition? > >Regards > >S.Sivasankaran