Valve management is an important part of the water network management. The opening and closing of the valve is the only way for the local network to stop water and overhaul, and it also has a direct impact on users. There are still many problems in the management of the valve: it is difficult to confirm the exact position of the valve; whether the valve can be normally opened or closed; which valve needs to be closed when a certain point in the pipe network is not closed; which user will be affected when the valve is closed; These problems by manual management is difficult to solve, so the use of computer technology for the management of network valves has become a necessity. First, the computer method of valve management Introduction The most convenient method of computer valve management is to establish the valve database and MIS system. This method is simple programming, the use of common database management systems such as FOXPRO, ORACLE will be able to meet the requirements. But it can not be a graphical query, but can not burst tube off valve and other professional analysis. GIS system will be the graphical data and attribute data together, unified management. After the establishment of the system, the user can carry out the bidirectional query operation from the graph search and the digit search to the graph with the exact position of the valve. The attribute data of the valve can be displayed on the same screen at the same time, which is convenient and intuitive. Second, the burst tube valve closed the establishment of the system Shenzhen City Water Company to establish a valve management GIS system, and on this basis developed a burst analysis subroutine. The system includes more than 8,000 municipal pipelines, over 3,000 municipal pipelines and more than 3,000 major user data. Now the system development methods are as follows: 1. The original data collection, finishing company drawn the city's 1: 10000 municipal water supply pipe network map, and in the map on the precise drawing of the municipal pipeline valve, and customized for each valve valve card, numbered archive. 2. The establishment of the valve database, user and pipeline database In order to query, statistics and site to find the convenience of the valve number is carried out by the various roads. Taking into account the universality of the database and AUTOMAP plug-in database capabilities, we use the FOXPRO database format to create a valve properties database with more than 5,000 records. We also use the FOXPRO data format, the establishment of more than 8,000 pipelines, more than 3,000 large user attribute database. 3. The graphics finishing, the establishment of the correct topology The use of AUTOMAP to provide the finishing function, the graphics finishing, sorting into a map with the correct topology. Specifically in the valve management system, is to establish the correct node, pipeline, valve connection. 4. Pipe network graphics on the valve, pipeline and other database data in the valve data, user data to establish the connection between the establishment of graphics pipeline, valve and external database in the valve, pipeline and user data connection, in order to map Number of two-way query or burst tube off valve analysis, search related valves, pipe users and other attribute information. 5. The preparation of closed-valve analysis program The above four steps are for graphics and data collation, after which will burst tube valve closing analysis system of secondary development. The system is based on AUTOMAP's embedded development language AUTOLISP secondary development. Including valves, pipelines, users and other figures of the two-way query, editing functions, data statistics and burst pipe analysis functions, now the analysis of pipe burst function, for example, describes the development method. Explosion tube analysis of functional modules should have a point in the pipeline failure, the timely and accurate response, indicating that the calculation of the pipe network should shut off the valve, involved in the pipe, the impact of users. The module includes the following subroutines: ①Initialization The initialization function is to load the topology into memory and establish connection with the external database. Prepare for calculation of closing valve scheme. ② specify the point of failure pipe network fault point can be pipe, node or valve, the user can specify the mouse on the map. The program returns the topology ID number of the point of failure. ③ closed valve program to calculate the valve closing strategy. This subroutine mainly uses AUTOMAP3.0 topology analysis function? FLOODTRACE function? These functions provide the function of network topology tracking, starting from a certain point in the network topology established by points and lines and automatically tracking all connections and corresponding downstream points of the point until the sum of the resistance values ​​of the paths passing through is greater than the specified Value so far. These functions return all the trace-to-point, line-topological ID numbers and get the corresponding attribute data. Subroutines use these functions to generate data for the affected pipe sections, nodes, and valves that should be closed, and shown in different colors on the graph. Can do a continuous off valve program. ④ closed valve program data query and report generation Can query affected pipe sections, nodes, users and the valve should be closed attribute data, and can generate text reports for editing, printing. ⑤ graphics printing AUTOMAP3.0 print order to print graphics. ⑥ reset delete valve closed after the calculation of the results of data labeling and color will be replaced by the original color, ready to do once again off the valve strategy calculation. ⑦ End Topology data is removed from memory and disconnected from the external database. Then exit the subsystem.
Molybdenum Rod
Molybdenum can increase steel`s
corrosion resistance in the acid-based solutions and liquid metals, thus
improve its wear resistance, hardenability, weldability, and heat resistance.
As an element which easy to form carbides, molybdenum can effectively avoid
oxidation during steel making process, and it can be used alone or mix with
other alloy element to achieve the best performance.
A pure molybdenum rod is a cylindrical bar made entirely of molybdenum, a chemical element with the symbol Mo and atomic number 42. Molybdenum is a refractory metal known for its high melting point, excellent thermal conductivity, and resistance to corrosion. Pure molybdenum rods are commonly used in various applications, including the manufacturing of electrodes, heating elements, and high-temperature furnaces. They are also utilized in the aerospace, defense, and medical industries due to their exceptional mechanical and thermal properties.
High temperature smelting additives
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