Investigation on the Strength of Ultra High Pressure Vessel Cylinder With Self-Protective Flat Steel Ribbons Wound

A unique type of self-protective Ultra-High Pressure Vessel (UHPV) cylinder with helically wound Flat Steel Ribbons (FSR) is proposed. The shielding properties of its self-protection in the hoop and axial directions of a FSR cylinder in the case of fracture failure, as well as quick-actuating of the tooth-locked end closure of this new vessel structure are both expounded. Based on its axial strength, a formula of the ultimate load-carrying capability of FSR layers is derived. The shielding function and self-protective capability of FSR layers to the UHPV cylinder are analyzed quantitatively in detail, and a design criterion is also defined. According to the formula and the design criterion defined in this paper, the predicted ultimate load-carrying capability of the FSR layers is 48.3% higher than that in previous references. Results from burst tests of 6 model vessels show that the brittle failure morphology of UHPV cylinders are changed with FSR layers and the potential hazard of failure of the UHPV is reduced. In addition, the cross fracture of the UHPV cylinder is shielded effectively and the derived formulation on the ultimate load-carrying capability of FSR layers is reasonable. UHPV cylinders designed according to the formula and the criterion can use much fewer FSR layers with the same shielding capability.