A pressure pipe is any pipe that is subjected to internal or external pressure, regardless of the medium in it. Pressure pipeline is a part in the pipeline, the pipeline is used to transport, distribution, mixing, separation, emission, measurement, control and stop the flow from the pipe and pipe fittings, flanges, bolts, gaskets, valves and other components or compression components and support components of the assembly. Well, what is the pressure pipeline, its role is what, pressure piping welding process what, below for everyone to understand.
Pipeline inspection standard
The inspection and inspection of the pressure pipeline include: appearance inspection, thickness measurement, nondestructive testing, hardness measurement, metallographic examination, pressure test and so on. Magnetic particle testing is nondestructive testing, a frequently used method. The ability of magnetic particle testing is not only related with the applied magnetic field intensity, depth and width direction, and defect defect ratio, defect shape, workpiece shape, size and surface state and possible defects related to the position. So there are different methods of magnetization.
1, the pressure pipeline is a system, interrelated, interactive, and affect the whole body.
2 、 the ratio of the length to diameter of the pressure pipe is very large, it is easy to lose stability, and the force is more complicated than the pressure vessel. The complicated flow state of the fluid pressure inside the pipeline, buffer, frequency change working conditions than the high pressure vessel (such as high temperature, high pressure and low temperature, low pressure, displacement, wind, snow, earthquakes are likely to affect the pressure pipeline stress).
3. There are many kinds of pipe component and pipe support materials, each material has its own characteristics and specific technical requirements, and the material selection is complicated.
4, the pipe may leak more than the pressure vessel, only one valve is usually five.
5, the pressure pipeline type, quantity, large, design, manufacture, installation, inspection, application, management links, and pressure vessel is very different.
Piping welding requirements and process
I. personnel quality
The welding of pressure pipeline, the main personnel is responsible welding engineer, followed by inspectors, inspection personnel and welder.
1. 、 welding responsibility engineer is an important person in charge of pipe welding quality, mainly responsible for the preparation and examination and verification of a series of welding technical documents. Such as weldability test, welding process qualification and report, welding plan and welding operation instruction, etc.. Therefore, the welding engineer should have rich professional knowledge and practical experience, strong sense of responsibility and professionalism. Often go to the scene, grasp the pipeline welding first hand information in a timely manner; supervise welders to conscientiously observe discipline quality of welding process; assist Engineering responsible for the common good of pipeline welding; the quality and exploration for the wounded inspection work to support and guidance, guidance and supervision of the insurance tube, baking electrode and release etc..
2. quality inspector and inspection personnel are directly welding quality inspection personnel, each inspection of their data on welding quality evaluation quality has a pivotal role. The quality inspector and examiner must first be approved by the competent department of training and examination to obtain the corresponding qualification certificates, certificates, and should be familiar with the standard and relevant rules and norms. It should have good occupation morals, enforce the law impartially, strictly grasp the inspection standard, does not allow the sentimental, resort to deceit. Only in this way can the authenticity, accuracy and authority of the inspection result be guaranteed, so as to ensure the authenticity and reliability of the welding quality of the pipeline.
3. the welder is the executor of the welding process and also the operator of the pipe welding. Therefore, the quality of the welder is of decisive significance to ensure the welding quality of the pipeline. A good welder should have good business skills, skilled practical skills is not a short duration of time can do, but through the actual exercise, even intensive training to mature, finally through the examination to obtain the corresponding welding qualification. This point, the relevant standards, laws and regulations on the welding skills, welding range and so on have made more clearly defined. A good welder must have good professional ethics, professional dedication, strong sense of quality, and be able to operate in accordance with the requirements specified in the welding process. In the welding process, concentrate on, not for external factors interference, don’t let go any influence welding quality of small links, do meticulous, and finally get excellent welding quality.
4., as management personnel, should establish certificate welder files, in addition to master certification welder qualification project, also should pay attention to welder daily performance assessment. Periodically check the welding work of each welder, including the inspection rate of the passing rate after radiographic inspection, into the welder’s file. At the same time, the system of rewards and penalties should be formulated to commend welders with stable welding quality. This provides a basis for the management’s assessment of welders. For those welders with better quality and stability, they can be appointed as welding tasks of important processes in important pipes or pipes so as to ensure the quality of welds.
Two. Welding material
The welding material is self-evident to influence the quality of welding, especially welding rod and wire directly into the weld filler material, will directly affect the weld alloy element content and mechanical properties, must strictly control and management. The following principles shall be followed in the selection of welding materials:
It should be matched with the mechanical properties and chemical composition of base metal.
Consideration should be given to the complexity of the weldment, the magnitude of the rigidity, the preparation of the weld groove, the position of the weld and the working conditions and service performance of the weldment.
Operational technology, equipment and construction conditions, labor productivity and economic rationality.
Welding worker’s technical ability and equipment capability. In addition, the welding material according to the pressure of pipeline welding, welding should be set up a level two level library and library management. The welding materials, storage sites, storage, drying, distribution and recycling of the construction site shall be strictly carried out in accordance with the relevant provisions. To ensure the welding quality for guarantee, composition and properties of the welding process stability and weld meets the requirements.
Three. Welding equipment
1. the performance of welding equipment is an important factor affecting pipeline welding. The selection shall generally follow the following principles:
Meet the welding requirements of the welding technology requirements.
The preferred to buy a national compulsory CCC certification of welding equipment manufacturers with high reputation equipment, comprehensive technical indexes of the welding equipment are studied, such as machine input power, duty ratio, main components, the main internal appearance.
Consider efficiency, cost, maintenance and maintenance costs.
It is very important to choose the special equipment with better comprehensive performance index as far as possible to reduce the welder’s labor intensity and improve the production efficiency. At home and abroad, many welding equipment manufacturers are dedicated aircraft, and played a brand. Therefore, the principle of welding equipment selection is preferred, and the equipment performance index is excellent. Only in this way can the welding quality be stable and improved.
2. the maintenance of equipment plays a very important role in the smooth operation of welding, improving the operation rate of equipment and ensuring the quality of welding, and it is also necessary to ensure the safety of operators. Therefore, welders should correctly use and maintain the equipment they operate, find problems in time and avoid hidden dangers. For the often damaged parts, reserve in advance, equipment should be maintained at the first time. In addition, the current and voltmeter on the equipment are the basis for assessing the welding process parameters, and should be fully equipped and guaranteed within the approved validity period.
Four 、 welding process
1. preparation of welding process documents. The welding process document is technical regulations or measures of welding operation instruction, is generally done by the technical staff, in accordance with the procedures and requirements of welding process documentation, the main welding test and evaluation of welding process, welding process instruction or plan, guide books and other content welding operation. Welding test is general for new materials or new technology, welding test is the basis of evaluation of welding process, the welding process that any evaluation should be in the welding test qualified or the after welding characteristics and process requirements. After the qualification of welding process, the process instructions can be directly used to guide welding production. For the important or important pressure piping project, the welding program can be prepared according to the welding process instruction or the welding procedure qualification report, and the welding construction shall be comprehensively guided.
2. implementation of welding process documents. As the welding procedure book and welding procedure qualification report are managed as technical documents, they are used to guide production practice, and are generally managed and maintained by technical personnel. Therefore, welding in pressure piping, often must prepare welding operation instruction, the principle of all pipe welding and specific technical measures and process parameters are explained clearly, and the welding operation instruction issued to the welder team, let all welders in learning and mastering the requirements in practical welding carried out executive. In order to ensure the welding quality of the pressure pipe, the construction behavior of the welder can be standardized and within the range of the technical standards and technical documents required.
In order to ensure the welding quality of pressure pipeline, except in the welding process in the strict implementation of rules and regulations to design welding process documents, must also be in accordance with the provisions of relevant national standards and regulations, strict inspection of welding quality. Welding quality inspection before welding inspection (including material inspection, quality inspection, and the groove size group on quality inspection, cleaning and groove welding environment and preheating before welding test, welding inspection (intermediate) positioning welding quality inspection, welding line energy measurement and recording, weld level and layer quality inspection), the test after welding (visual inspection and nondestructive testing). Only through strict inspection and supervision can the process discipline be realized, and the welding process is always in a controlled state so as to effectively guarantee the welding quality of the pressure pipe.
Summary: about what is the pressure pipeline and pressure pipeline welding process, what are the relevant information for everyone here, and I hope this article will help you. If you don’t understand anything, you can leave a message for me in the bottom. Oh, we will answer for you as soon as possible.
Water Leakage pipeline pipeline