petal fabrication dished end with clad plates

Hokkai Provided many larger Dished Heads to our clients every years.

Hokkai will use petal fabrication or segment forming for some larger dished heads. the below case was one larger size 8000*61.5 that we done for one of our clients.

1,Material name: SA516GR70N+SA240_304L clad steel plates,

as ASME SEC II SA516&SA240,Premissible dimension variation ,Flatness, inspection and test SA/A-264/SA/A-20/SA/A-480.Mechanical properties shall as per material specification;chemical composition as material specification SA-516&SA-240

Heat treatment raw material specification conform to the following: the base metal shall be normalized and para 15.2 of SA480 for cladding metal

simulated heat treatment as the holding temperature 1157+/-25F with 7.5hrs .Ultrasonic examination shall be done as SA-578 Level C&S1 and SA-264 Level CL.1.

the minimum shear strenght of clad plates shall be 40,000PSI. the cladding shall be interpreted to be unbonded when there is 50% loss of back reflection accompanied by an echo indiation from the plane of the inteerface of the clad and backing steel.

The tension test specimens from plate shall be orientated in the direction perpendicular to the final direction of the plate rolling

2,Dished heads forming specification

Product name : 2:1 approximate ellipsodial dished heads made by SA516GR70(Normalized)+sa240-304L requried Ultrasonic examination test  

designed,fabricated and inspected as per ASME SEC VIII DEIV.2 2015ED

Scope of work: mateiral shall be provided by clients/ marking,cutting/forming/edge prep/marking/packing

dimension and tolerance: as clients drawing/ approvaed fabrication drawing requried but must be show client's order number

fabrication: transfer the original identification marking before cutting.the forming of dished heads shall comply with the followings

the dished heads manufacture shall furnish the detail manufacturing specification to purchaser for his aeptance prior manufacturing.  

cold working shall be performed in the manner which will not have harmful influence to the application and material of heads

dependent on the dimension,shape, plates thickness and material of head, the appropriate forming method shall be considered in the performance of head forming.

the welding reinforcement may be ground to flat, if necessary, but reducing the thickness of weld reinforcement less than the base metal cause form the gringing or forming is not acceptable. welding repair shall be prohibited except approval of client.

Product Categories : Clad Material Head > Clad Material Torispherical Head