Needle valve coupler with grinding system

The needle valve is one of the three pairs of precision parts of the diesel injector. Its processing capability and product quality directly affect the injector's production capacity and performance, thus affecting the capacity and performance of the whole machine. At present, in order to meet the large-scale production requirements of needle valve parts, the grinding process is mainly used, and the grinding process has the characteristics of high efficiency and high precision. However, the processing and testing processes in the process of grinding are independent of each other and resources are not available. Effective integration, automation, and informatization are not high. In order to further improve the processing efficiency and processing quality, realize the automatic grinding and reduce the human factors, this paper studies the matching system of the needle valve.

Needle valve coupling part grinding strategy

The matching strategy of the needle valve coupler is the basis of the grinding system. The grinding system needs to comb the grinding process and organize the machining process reasonably and orderly.

The specific grinding strategy is as follows: the needle valve body and the needle valve complete the pre-process of the even surface finishing, and the operator receives the production task list and first picks the material. The middle hole and surface grinding machine is used to process the hole and seat surface of the needle valve body. The equipment has a single machine automatic loading and unloading function. After the processing is completed, the middle hole is detected after the line, and the test result is fed back to the operator for the determination of the processing quality. If it is qualified, the processing part will be matched with the grinding process. If it is not qualified, it will be stored in the unqualified product area. According to the test results, the middle hole grinding process is controlled. The needle valve is equipped with a cylindrical grinding machine for grinding. It has a single machine automatic loading and unloading function. The outer diameter of the needle valve is matched according to the size of the middle hole, and the on-line inspection is performed at the same time to ensure the matching. Quality, the needle valve coupler is paired one by one.

Design of needle valve fittings with grinding system

1. Analysis of the needs of the grinding system

At present, the automation and informationization of the needle valve fittings are not high, and the various aspects of the grinding process are relatively independent, failing to achieve a high degree of automation of the process, and failing to work with MES (Manufacturing Execution System) and CAPP (Computer Aided Process Design). The system shares information, lacks control over the quality of the processing process, restricts the improvement of production capacity and quality, and increases the production cost of the enterprise.

Based on the urgent need of enterprises to improve production capacity and quality, this paper proposes a needle valve fitting grinding system, which optimizes the matching process of the needle valve coupling parts, realizes the automatic matching grinding of the coupling parts, and carries out the existing MES and CAPP systems. Integration, and control feedback on the quality of the process, reducing manual participation.

2. Overall design of the grinding system

The goal of researching the needle valve fitting grinding system is to achieve a highly automated grinding process, based on the current grinding strategy, to maximize the integration of resources, improve the level of information and automation, the system scheme is shown in Figure 1.

Figure 1 Needle valve coupler grinding system solution

The development of the needle valve fitting grinding system adopts a three-layer architecture, which is divided into a presentation layer, a business logic layer and a data access layer. The presentation layer is the uppermost layer, mainly for the user's request acceptance and data return; the business logic layer is located between the presentation layer and the data access layer, and is responsible for the operation of the data layer; the data access layer is the operation layer for the original data, and the data is realized. Add, delete and change. The dependency between layers is downward. The change of the upper layer design has no effect on the bottom layer, which enhances the security of the system and facilitates the system to expand and migrate. The overall structure of the needle valve fitting grinding system is shown in Figure 2.

Figure 2 Overall structure of the needle valve fitting grinding system

3. Design of the function module of the grinding system

The needle valve fitting grinding system can be divided into six main functional modules according to requirements: grinding task management module, grinding processing management module, processing quality management module, running status monitoring module, even BOM management module and user management module. As shown in Figure 3.

Figure 3 Functional structure design of the needle valve fitting grinding system

(1) The matching task management module is integrated with the MES system to obtain the production task list, manage the task list, and update the processing completion status in real time. The grinding plan is the source of the data of the grinding system and the basis of the data of other modules.

(2) The grinding processing management module integrates with the CAPP system according to the production task list to obtain the coupling processing technology of the coupling parts. According to the requirements of the even part processing, the processing parameters of the needle valve body and the needle valve are set, including the grinding wheel rotation speed, the dressing frequency, the workpiece rotation speed, etc., and the machining parameters can be automatically corrected according to the detection result to ensure the matching part quality.

(3) The processing quality management module collects the processing quality data of the needle valve body and the needle valve, and performs the SPC statistical process control, uses the control chart to monitor the process, analyzes and evaluates the machining process, and timely corrects the machining parameters to make the machining process more Stable, at the same time complete the matching work of the needle valve couple data, and feedback the successful sub-quantity and quality information to the task list.

(4) The operation status monitoring module realizes the monitoring of the working state of the machine tool body, the detecting device, the automatic loading and unloading device, the cooling device, etc., and performs emergency treatment on the abnormal state, and feeds the state information to the MES system to realize information sharing. .

(5) The even BOM management module can query the process BOM of the needle valve coupler, obtain the BOM of the needle valve coupler through integration with the CAPP system, and automatically update the data with the CAPP system.

(6) The main functions of the user management module include new user addition, user information maintenance, user deletion, and login management. The system administrator can add, modify, and delete users. The user's role permissions are assigned by the administrator and the corresponding menus are configured. The user authenticates by logging in, confirms the permission to load the corresponding menu, and can modify the personal password and maintain the basic personal information.

4. Matching grinding system database design

A database is a collection of logically related data, usually for the purpose of achieving a certain purpose, with a specific user, reflecting the real world of data aggregation. The database of the grinding system is the basis for realizing data management, completing the grinding automation, and improving the processing efficiency. Designing a good database can greatly improve the performance of the grinding system, and also facilitate system development and subsequent system upgrade and maintenance.

The database design of the needle valve fitting grinding system is mainly carried out around the production task list. The basic information is derived from the MES and CAPP systems. The integration technology is used to obtain the task list and related processing technology information, and thus the processing machine tool and the loading and unloading mechanism are obtained. Operating parameters and status of hardware such as detection devices and grinding wheels. Each production task list in the system corresponds to one or more processing parameters, and the appropriate processing parameters are selected according to the needs for processing. After processing, a plurality of corresponding quality data are generated, as the basis for the grinding, through the analysis and feedback of the quality data, Process control. At the same time, through the query function of the database, all the data information associated with the production task list can be obtained, such as the state of all the hardware involved in the grinding, so that the system can perform corresponding disposal in time.

Realization of the matching system of needle valve

The needle valve fitting grinding system adopts the B/S layered architecture, and the code separation technology is applied to separate the background code from the page code to ensure the system runs safely. The server-side operating system adopts Windows Server 2003, and the client adopts Windows XP. Using SQL Server 2005, the development tool uses Visual Studio 2005, the programming language uses C#, and the browser uses IE6.0 or higher.

The Web Service access technology is used to realize the integration of MES and CAPP systems, and the parts that need to be integrated are encapsulated into Web Service. The even part matching system is accessed through a specific API, and the XML format is used as an intermediate format for data exchange to realize cross-platform information sharing. .

In order to improve the development efficiency of the coupling grinding system, the OR-Mapping component is used to manipulate the data in an object-oriented manner, so that it does not need to care about the storage method and SQL statements of the underlying data, which greatly simplifies the code development work and facilitates subsequent operations. Expand maintenance work.

Conclusion

The needle valve fitting grinding system is integrated with the existing MES and CAPP systems, and the functions of the MES system are further expanded to integrate the relatively independent links in the grinding process to automate the grinding process. Use measurement data for quality control of the process. The processing parameters are corrected in time to realize the closed-loop control of the grinding process, which reduces the unstable factors in the grinding process and is beneficial to the mass production of precision parts. It not only saves costs, but also increases production capacity, which has certain reference significance for enterprises to implement informationization and automation.