Shenhao enforces the most stringent quality control throughout the whole production processes of seamless carbon and alloy steel pipes involving billets inspection, heating, piercing, rolling, sizing and reducing, straightening, flaw diction, visual and dimensional inspection, etc.
1. All raw materials that we use for making industrial pipes will be tested before production. Sampling inspection will be conducted for the chemical and mechanical properties of pipe billets. Unqualified raw materials will definitely not be used for production.
2. In the process of billets heating, it will be tested whether the billets are uniformly heated or not and whether they reach the temperature needed for piercing.
3. During the course of piercing, we will test the geometric dimensions of hollow billets and carry out visual inspection on their internal and external surface quality. Qualification or not qualification will be judged based on the production process sheet.
4. Wall thickness and uniformity of longitudinal wall thickness are mainly tested in the sizing and stretch reducing process.
5. In straightening process, we will inspect the straightness of steel sections and control in with 1mm/m.
6. Online eddy current flaw inspection with high automation will perfectly ensure the quality of steel pipes.
7. In manual inspection process, we conduct visual and dimensional inspection to the tubes. Defective and unqualified tubes are not allowed to be packaged and warehoused.
8. Tests in all processes have record. Finished products will sampled and receive chemical and mechanical properties inspection in the lab. Test reports can be sent to customers.
9. Before delivery, we can offer customer product quality certificate and accept examination by the third party test companies such as BV, SGS, etc. They can witness the whole on-site test process in the lab and recognize our test reports.
10. For regular customers, we accept a term of payment that money can be paid if they are satisfied with the products after examination at the destination port.
Shenhao built a state of the art laboratory for inspection and physical and chemical analysis of seamless steel pipes.
DFY-12 automatic analyzer with high speed carbon and sulfur determination, metallographic test equipment and full set of physical and chemical equipment are used to test the chemical compositions of steel tubes including C, Si, Mn, S, P, etc.
Hydraulic universal testing machine with computer online control is mainly used to test the mechanical properties of steel pipes by stretching, compressing, bending, shearing, etc. thus gaining their tensile strength, yield strength, elongation and other properties.