High Temperature service tube are typically knows as heat exchanger tube, which operates at 400 degree Celsius to 1100 degree Celsius.
高温服务合金钢管称为铬钼管。
基本上有三种类型的高温钢管：
ASTM A179,A192,A210规格涵盖高温服务的碳钢无缝管。这些管子用热交换器，冷凝器，高温材料应提供给规格A 530。
ASTM A213, A209 specification covers Alloy Steel Seamless tube for high temperature service. These tube are suitable for bending and similar forming operations, and for fusion welding at high temperatures. High Temperature Alloy Steel tube are also considered as low Alloy Chrome Moly grades.
高温不锈钢管道在短期或长期内暴露于升高的温度时保持其机械性能。
High Pressure and Temperature Service Seamless Pipes are application for heating-pipelines, containers, coal-saving devices superheaters and reheaters of high temperature and high press boiler by the main standard:
首先，高压无缝管质量问题
Boilers with high pressure seamless pipe is an important material for manufacturing boiler pipe, the quality of how it will be directly related to the the boiler manufacture of quality so that the quality of the installation and use of quality. High pressure seamless steel quality should by steel pipe factory to make a guarantee, but in the case of short supply, the use of high-pressure supplied to the boiler manufacturers seamless steel pipe always found some quality problems, it made boiler pressure components such as water wall tubes, convection tubes, superheater tubes, heat exchanger tubes leaking or burst pipes phenomenon have occurred, has become a big problem that plagued boiler product quality, this boiler manufacturers and users are opinions.
In the case of a seller's market, the boiler manufacturer almost assume full responsibility for the material supply side, including; how to control the quality of the boiler tube is now a boiler manufacturers are increasingly concerned about the problem, the solution is no more than two : a root-by high pressure seamless steel pressure test; another high pressure seamless implementation of 100% eddy current testing.
Second, high pressure seamless pipe defects and injuries
优质的金属材料按照材料科学，化学成分，物理性质，几何形状应连续，纯净和均匀的观点。如果这三种缺乏或由金属材料损坏，则被认为是有缺陷的。If the metallic material is a discontinuity exists in geometry (i.e. does not close or not dense or non-dense), for example, cracking, shrinkage, from the skin, the dimple, layered, pinholes, slag, etc. Scar (referred to as the injury) exists that the metal material, it does not include the discontinuous chemical composition or physical properties of discontinuous.
As can be seen from here, defects contains wounded. The boiler steel smelting and rolling process in the same possible defects and injuries. According to Steel Pipe Plant, boiler tube defects (here mainly refers to the injury), mainly in the surface, more than the inner surface and the outer surface. Raw material (billets), about 70% of these defects from billet enough oxygen blowing in the slag material, shrinkage and other remnants of folders, use it rolling steel pipe there may be transverse cracks, mezzanine, folding, heavy leather defects longitudinal cracks are mostly the strain caused by the rolling. If these defects or wounds in the high pressure seamless, it appears that the material is not continuous, the compactness of the material inside the damage in the hydrostatic test, there may be leaks, made of boiler pressure parts running is likely to leak or burst pipe. Because of this, in order to ensure the quality of boiler tube, whether Chinese or foreign boiler seamless steel tubes for standard defined as a process performance guarantee, the pipe should be out by the root for hydrostatic testing.
Third, the hydrostatic test of the boiler tube density test
一般认为，静水压检测的目的两种：一个是手艺的静水试验，其目的是测试材料（或组件）进行泄漏，密封性能的测试材料;另一个确认的静水压试验，目的是测试材料（或成员）的强度是否充足。
从这里我们可以看出，锅炉管的静水压试验是静水压试验的过程，材料密度试验，测试材料是连续的，是否密集;它不是验证强度测试。从材料力学理论的强度看，无缝钢管是薄而薄的部件，其小直径，薄管壁厚度较薄的压力较薄。
Specification, standard and identificationSeamless pipes are extensively applied for the nuclear device, gas, petrochemical, ship building and boiler industries. Seamless pipes dominates 65% of market share in Chinese boiler industry.
