The optimization of the hottest cutting parameters

Optimization of cutting parameters and processing quality can effectively reduce the production cost of molds

Abstract: in a factory producing high-end auto parts, the refitting of the whole mold milling production line lasted for 5 years. Production was never interrupted during the refit. The project combines the practical experience of automobile manufacturers and the skills of process technology partners. It is a fruitful cooperation

to effectively reduce the auxiliary time, we must not only adopt high-speed or efficient processing, but also adopt automatic production units equipped with pallet exchange system. In the actual production of body parts stamping in the BMW automobile factory where Dingolfing is located, from mold manufacturing to the most typical data processing, the refitting of the production line and the renovation of two machining centers, the installation and expansion of production units including two new machining centers, The two new machining centers are droop and rein machine tools of Dorries scharmann Technology (DST): FOGL 3265k and t2550 r30c

the results achieved so far are that the processing time has been reduced by half and the working area of the equipment has been reduced by one third. The premise of this achievement is that the new pallet system has been used in BMW plant in Dingolfing for about one year

this is the result of cooperation between the die manufacturer of BMW and the partner of Dorries scharmann Technology (DST) Co., Ltd. The die maker of BMW automobile factory has formulated an open structure flexible workpiece flow scheme. DST company, as the general contractor, is responsible for implementing the user's planning objectives

BMW 5 Series/6 Series/7 series models are transported on the assembly conveyor belt. Car parts such as body must first be manufactured into body in white by punching machine, and then painted. The stamping die is produced by the same sample factory. In terms of mold manufacturing, production is to arrange multiple shifts for operation, so as to supply parts for the stamping machine in the factory

the concept of mold here refers to the following parts as molds: female and male molds, which accurately shape the sheet metal into the car body under a certain pressure, so that the car body parts can then be accurately joined with the specified size

in order to manufacture plates, precision production dies are required. A deviation of 0.02 mm is allowed. On four machining centers, different milling heads and machining tools are used to optimize production. On the machine tools of droop and rein brands, solid 25 ton cast steel parts (each part is a complex part composed of up to five large parts) form its outline. The task of the machining center is to roughen the parts of the mold first, and then finish machining according to the final state of the parts. The assembly and finishing of the mold are carried out manually by experts

mold production: here, each milling center constitutes a related equipment in the whole. This equipment,

is physically integrated into the processing unit through the support plate, while in virtual terms, it is integrated into the processing unit through the cam system

shorten the auxiliary time

high quality requirements require a long processing time: for the three parts of female die, male die and automobile plate, the quality must be completely matched with each other, and the requirements are very high. Until the final acceptance of each die provided, the user must conduct multiple inspections: it must be formed according to the specified pressure, and the performance test of 1000 flawless stamping parts must be completed. Finally, the stamped parts should be confirmed to fully meet the specified quality standards

before 2002, there were relatively long logistics transmission time, assembly and adjustment time and waiting time between various processing stations. This causes a typical unfavorable ratio between basic time and auxiliary time for the processing of parts with a production batch of only 1. After that, the company made a decision to invest in novel intelligent technologies at BMW, and then made programmatic considerations with its partner DST

DST company, a contractor, can not only provide first-class processing centers, but also participate in the organization in the process of project implementation. In order to find a lasting and future oriented solution, the technical manager of DST company in charge of the project first discussed the implementation conditions and practical goals with his customers

in the production workshop, the planned objectives of the equipment transformation project should be significantly reduced in terms of processing time and equipment operation area. The specific goal is to reduce the previously required working area by at least one third, and the whole time of processing molds by one quarter

the network system coordinates the whole process

it is worthwhile to plan for projects involving a wide range of contents. Since the commissioning of the pallet system, this bottom pallet system connects the processing stations of the efficient production process in the production unit. The network system coordinates the whole processing process and makes the processing process of all process chain links transparent. On the display of the control device, each worker can see the progress of the task and understand the current process reserve or the workpiece replacement that may be carried out at that time

equipped with modern sensors, the pallet exchange system is actually on the conveying track at the bottom level of the workshop, which avoids the collision of the same heavy load. In terms of achievements, the installation and adjustment time has been shortened from an average of one hour in the past to (5 ~ 10) minutes now

intelligence, confidence and execution

put processor chips in control systems and software packages and on DST devices. The open structure system can have the greatest flexibility, which is needed by the die makers of BMW when they quickly change models. The system manages cad/cam data and coordinates these data with planned values such as quantity, cost, budget and other particularly important project parameters. These data are listed in files and archived

is responsible for converting CAD data, and the data directly input is cam program. Tebis software company has developed this tool for sample, mold and tool manufacturing

DST company has worked out new tasks as the general contractor of BMW Group. The milling process is incorporated into the overall system with reliable functions, and the four milling stations are connected with each other. In case of failure, the machine tool experts of DST company are not only responsible for identifying the failure, but also ensuring the shortest and fastest possible contact path. For this, the diagnostic system of DST is installed on four machining centers. The remote service mode allows machine tool experts to coordinate with BMW to make equipment operation records and identify machine tool data for remote diagnosis. In case of failure, the files stored in the digital form of 2. The main motor source of the tensile testing machine is not lit will be automatically connected to the corresponding processor

in addition, the maintenance staff also received some concise tips about the cause of the fault and troubleshooting. In addition, some graphics also show the status of the machine tool. With these supports, the maintenance staff saved time and significantly reduced downtime

production line: there are four machining centers integrated in the production unit, which connect the assembly and adjustment station and the manual operation station through the pallet system

two conveying trolleys with the size of 2500 x 5000 mm can be loaded to connect each processing station.

the 93 meter long two lane track system is the basis for all logistics, manual and automatic workstations to be intelligently connected into a processing unit. The pallet conveying trolley can load two pallets. At the feeding station, the conveying trolley loads the blanks grabbed from the truck onto the pallet. Then, the conveying trolley transports the pallet to each assembly and adjustment station and processing station at the conveying speed of 15 m/min according to the planned operation route

the pallet system ensures the completion of all conveying operations and processing procedures of the same workpiece on a pallet, from the transportation of blanks to the output of locally consistent workpieces, which contributes to significantly reducing the auxiliary time

gantry machining center high production efficiency

belonging to the droop + rein brand, FOGL type multi-functional high-speed cutting gantry machining center with upper crossbeam is designed for semi finishing mold contour and mainly for finishing. In model making, it is used to process the mold cavity of the future body shell

in mold manufacturing, in order to solve the tasks arising from the new plan, experts from DST company put forward measures to transform the equipment. Because the moving mass of FOGL machining center remains constant, the acceleration is not affected by the size and weight of the workpiece. The fast travel speed of the x-axis and Y-axis of the machining center is up to 50 m/min. The z-axis reaches 30 m/min. this gantry machining center is designed for machining the contour of high-precision molds, and can obtain particularly good workpiece surface quality. Because the moving axis of the machining center has high dynamic performance, the machining time is greatly shortened

the machine tool control system adopts FIDIA C20 system. FOGL machining center is used for mold manufacturing after model manufacturing and upgrading. Here, the T-series gantry machining center of droop + rein brand is FOGL precision machining. The following are summarized by the manufacturer's technology department to prepare the center for pre-processing

due to the need of automatic cutting, three T25, 50R and 50c gantry machining centers are connected to form a production unit, which are responsible for rough machining and semi finishing of stamping dies. When coordinating the processing range of FOGL machining center with the three machining centers mentioned above, the four machine tools should have a higher processing load. In addition, because of its high rigidity and shock absorption performance, gantry machining center can obtain high production efficiency. Therefore, the main components of the machining center are cast iron structure, thermosymmetric frame structure and hydrostatic guide rail on all shafts. This kind of guide rail not only has high rigidity, but also shows excellent shock absorption performance

the processing time is reduced by half

the high moving accuracy of x-axis and Y-axis and excellent processing surface quality are the important role of the rack double pinion drive system in the upgrading of Jinan assaying material experiment technology. The drive system ensures the same rigidity condition and outstanding dynamic performance of the shaft at any position of the shaft