| 1.Seamless steel pipe is a long steel with hollow | | | | steel-wood furniture on the commonly used square, |
| sections and has no joints surrounding the steel bar. | | | | rectangular tube. |
| It is mainly used as a pipeline to transfer the fluid, | | | | 2.The pressure of seamless steel pipe |
| such as oil,natural gas,water and some solid | | | | Pressure pipelines are generally composed of pieces |
| materials,etc. As compared to the flexural torsional | | | | of standard parts, so the pressure pipe design |
| strength in the same light, it is an economic | | | | component is the selection of its standard parts. the |
| cross-section steel. The seamless steel pipes are | | | | pressure level of pipelines is determined to the |
| widely used in the manufactures and mechniacal | | | | pressure level of its standard parts. |
| parts,such as the oil pipe, automotive transmission | | | | Pipeline pressure level consists of two parts:one is |
| shaft,bicycles aircraft,as well as buliding construction. | | | | nominal pressure rating which is expressed in the |
| With steel pipe manufacturing, annular parts can | | | | nominal pressure of the standard parts. The other is |
| improve the material utilization, simplify the | | | | wall thickness rating which is expressed in the wall |
| manufacturing process, save material and machining | | | | thickness of the stand parts. |
| time. For example, the roller bearing rings and the | | | | The pressure grade of the pipes: |
| jack sets and so on have been widely made of steel | | | | The parameters of channels characteristics which are |
| pipes. Cylindrical rube can delivery more fluid since the | | | | determined by the nominal pressure level and wall |
| circle has the largest areas under the same | | | | thickness are called the pressure grade of the |
| circumference. In addition, the ring cross-section | | | | pipes.the determine of the pressure grades is not |
| bears internal or external pressure, the force more | | | | only the basis for pipeline design, but also the core of |
| evenly, so that vast majority of tubular steel pipes | | | | design. It is the basis of the arrangement of pressure |
| are cylindrical rubes . However, the tube also has | | | | pipe, and pressure pipe stress precondition for |
| some limitations, such as in-plane bending conditions, | | | | checking the design. and it is also an important factor |
| the pipe on the better side, rectangular tube bending | | | | which will affect investment and reliability. |
| strength, and a number of sets of frames, | | | | |