1. Self-design of rubber formula: 

 The rubber formula used in our marine oil/gas hoses is independently designed by our technicians through many strict tests. Its performance indicators such as low temperature resistance, oil resistance, wear resistance, interlayer adhesion strength, etc. all meet the requirements of GMPHOM2009 specification, ensuring that the products produced have excellent quality. 

 2. Independent design of flange joint: 

 1), flange selection forged steel flange, the maximum carbon content of 0.25%, according to ASTM A-105 standard. 

 2) Flanged joints are made of deoxidized or semi-deoxidized steel with a carbon content of 0.23%, in accordance with ASTM A-106A or B. 

 3) Flange rating according to ASTM B16.5 Class150 / 300. 

 4) Flange corrosion treatment is hot-dip zinc plating, according to ENISO1461, the minimum coating thickness is 85µm. 

 5) Flange flaw detection, X-ray photography according to EN1435,100% 

 6) The parts welded to the joint shall be deoxidized steel or semi-deoxidized steel with carbon content of 0.23%, and the welding shall be in accordance with ASME VIII Annex 6.  Flange joint material selection meets standard requirements. 

 3, raw material testing, finished product inspection equipment is complete: 

 We have the certificate of "A-level self-built R & D institution" issued by China, and have advanced experimental instruments to test the physical and chemical properties of materials. The experimental testing methods are strictly based on national or international standards, and the experimental data are reliable.  The physical and chemical properties of rubber compounds include density, Mooney viscosity, strength, hardness, elongation, oil resistance, ozone resistance, aging resistance, wear resistance, temperature resistance, etc.; the tensile mechanical properties of rubber, cord and steel bar are tested.  The testing of finished pipes is mainly carried out by large-scale testing machines, such as tensile, bending, torsion, pulse and flattening testing machines, which are jointly developed and designed by Zebang Company and equipment enterprises. 

 4. School-enterprise cooperation to ensure scientific design scheme: 

 All our offshore oil pipes are designed independently, and together with doctoral students and graduate students from China University of Petroleum (Beijing), Shanghai Maritime University and South China University of Technology, we jointly design oil pipe structures according to the sea area and sea conditions where customers are located, and carry out oil pipe mechanics calculation and finite element simulation research to ensure the scientificity of the design scheme.  Burst pressure, minimum bending radius, tensile stiffness, torsional stiffness, bending stiffness, radial stiffness and allowable radial extrusion force of tubing are calculated by finite element software abaqus; FPSO-hose-tanker coupling hydrodynamic calculation, mooring buoy-hose-tanker coupling hydrodynamic calculation, minimum bending radius or curvature, distribution of tensile force along pipe length direction, etc. are calculated by hydrodynamic software orcaflex.