The invention provides a fastening device for a
rocket engine shell mold with a large length-
diameter ratio. The fastening device comprises two part bodies, wherein curved grooves are arranged in vertical ribs of two adjacent part bodies; and a clamping device is movably connected to the outer surface of one side of each part body; and each clamping device comprises a pull rod, two lock catches, abolt, a pin shaft, a nut and a
gasket, wherein the two lock catches are fixedly arranged on the outer surface of one side of each part body, and the two lock catches are movably connected to the pinshaft. According to the fastening device, the space required by operation can be reduced, disassembly and
assembly do not need to enter the mold, the size limitation on a product during conventional bolt fastening connection is broken through, axial and radial simultaneous constraint is realized, the fastening surface is larger, the fastening effect is better, finally, the fastening mode is simple, disassembly and
assembly can be realized without tools and equipment, the operation is convenient, the
working hours are greatly shortened, and the
assembly efficiency is improved.