Tool management

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The tool management is in the machining requires manufacturing to the information on the tools available to organize uniform and to integrate the environment. The tool data are stored in a database and are recorded and used with the tool management software. In contrast to a general solution for the management of equipment , tool management includes specialized technical data fields, graphics and parameters that are required for use in the manufacturing process .

A tool in CNC production usually consists of several individual parts. Correct assembly of the individual components to form such a complete tool is a prerequisite for an error-free value chain . For the machining of a part with the CNC machine ( operation ), several complete tools are required, which are documented in a tool list. Every component, every complete tool and every tool list has an identification under which the associated specification can be found.

The tool management is divided into the documentation of the tools ( master data ) and the logistics ( movement data ).

The documentation includes at least all information that is required for a smooth and traceable manufacturing process. It can also be used to manage spare parts, empirical values ​​for use and the associated files. Functions are available to maintain, process, print and exchange data with other applications.

The logistics deals with the need for planning, inventory and the location of the tools. On the one hand, it includes storage and purchase of the individual parts with a corresponding evaluation of consumption. On the other hand, the movements of the assembled complete tools can be planned and coordinated within the company.

Tool management master data

The master data describe the tools with regard to their geometric properties, structure and possible uses. The information is divided into the actual description of the tools ( specifications ), the regulations for their use by people ( work instructions ) and the information for use by machines ( instructions ). The master data describe a tool completely in qualitative terms, but without worrying about the availability of the real copies.

Components (tools)

Scheme for characteristics

The components are individual parts which are combined to form complete tools. Components are purchased as a unit and stored in the tool dispenser. A distinction is made between cutting components (e.g. indexable insert ) and non-cutting components (e.g. collets ). Cutting components are worn out during use and must therefore be replaced and purchased periodically. Non-cutting components can be used practically without restriction in normal use. They are usually procured together with a new machine tool. Fixtures are treated like non-cutting components.

  • The header data are structured uniformly for all components and contain information such as the designation, the order number and a unique article number. Each component is assigned to a tool type , which determines the type and amount of descriptive data fields. In addition, each component is assigned to a tool class that belongs to a tree structure defined by the user , which is used to find the tools according to technical criteria without specifying numbers.
  • The descriptive data (geometric values) differ depending on the tool type . The fields are defined in the item characteristics bar . The meaning of geometric data fields is recorded in schematic images. The DIN 4000 contains a proposal for Special Instructions and images for explanation.
    DXF drawing according to BMG standard
  • Different graphics for different tasks are either saved directly in the database or assigned to the component via a file link. As a rule, four types of graphics can be distinguished:
  1. 2D drawings e.g. B. in DXF format according to BMG or DIN standard for the geometric information.
  2. PDF files from the tool manufacturer as data sheet with exploded view .
  3. 3D data (e.g. STEP or STL ) for use in CAM systems.
  4. Photos (e.g. JPG ) as informative graphics.
  • For the cutting components, cutting values ​​are stored for optimal cutting performance. The values ​​for infeed, speed, feed , cooling and type of processing are specified for various materials .

Complete tools

The complete tools are made up of several components. At the rear end there is the component that fits the tool holder of the machine, on the other side there is the cutting component (e.g. drill or indexable insert). In between, different components (e.g. extension, collet) are used to achieve the desired geometry of the complete tool. The documentation of the complete tool describes how the components must be assembled in order to avoid misunderstandings or errors and to ensure that the geometry used in the CAM system corresponds to that of the real tool in the workshop.

  • The header data contains information such as the designation, a unique ID number. and the assignment to a tool class.
  • The geometric fields are generally calculated directly from the values ​​of the components used. In the case of adjustable tools (e.g. fine boring tools with adjustable diameters), additional information is saved for the complete tool.
  • The assembly instructions include the parts list of the required components and contain additional information for assembly that is important for the specific complete tool (e.g. setting tolerance +0.03 / −0.01 mm).
  • The cutting values ​​are typically adopted by the cutting component as a suggestion in the complete tool. They can then be adapted to the specific situation in this complete tool, because z. B. extended tools require different cutting values ​​than short clamped tools. Based on concrete experience in the workshop, the information is continuously improved and automatically made available in the CAM system for NC programming.
  • The setpoints for the presetting serve as a specification when measuring the tool on a tool presetting device. In addition to the target values ​​for the geometry, the exact location and the method for the measurement can be specified so that e.g. B. with a grooving tool it can be determined whether the left or right cutting corner is to be measured.

Tool lists / operation

The tool list contains all of the complete tools that are required for one work step. It is printed out as a setup list and is used for commissioning and provision of the complete tools. It usually also contains instructions and information that are not directly related to the tools (e.g. clamping devices, clamping plans, NC program , clamping pressure, etc.) so that all documents can be called up together.

  • The header data include information such as the designation, a unique identification and the allocation to suitable machines. The identification is z. B. the combination of "part number + operation" is used. The drawing number can be used instead of the part number.
  • The list of tools contains all the complete tools required for the operation, together with the space provided in the machine (T number, turret). This list also includes those requirements for the complete tool that are specifically valid for this operation (e.g. minimum cutting edge length). The complete tools are listed in the order in which they are used in the NC program.
  • The print output (set-up list) is used to pick the components and assemble the complete tools in the tool output . It contains the required components with storage location and the important geometrical information and tolerances of the complete tool.

Auxiliary tables

In addition to the actual tool data, auxiliary tables simplify data acquisition by selecting values ​​from a table instead of having to enter them. Compared to manual entry, this ensures more convenient and uniform data acquisition.

  • Joining conditions are specified on both sides of a component, which determine which geometrical requirement another component must meet so that it can be added when assembling the complete tool. If a component on the right side has the same joining conditions as the next component on its left side, the two can be joined together. The use of joining conditions makes the search for suitable components easier and safer. When the component is recorded, the correct joining condition is selected from a table on both sides.
  • Joining conditions for tools
    A list of the materials is required for the assignment of the cutting values. The list contains different qualities and several common names for the materials, especially the name used individually in the respective company.
  • The tool classes are used to organize the tools from a technical point of view. All tools assigned to the same tool class are suitable for the same task, but they have different sizes. The tool classes are organized in a tree that can be adapted and expanded by the user.
  • The tool types with the associated images describe which geometric values ​​are required and where they are measured. Each tool type is assigned a feature bar that defines the data fields of the components.
  • The locations are used in logistics in order to be able to specify the location of the complete tools and components. They are an image of the manufacturing plant and contain all the places where tools and equipment can be. They are divided into storage locations, interim storage, creation and production units (machines). Several locations are combined into departments and locations. The places themselves can be divided into individual places. The level of detail and the depth of the structure are only defined to the extent that this is actually necessary for the logistical aspects.
  • The cost centers are used in logistics to evaluate the consumption of tools in the various departments (e.g. turning shop). When a component is removed from the warehouse, it is specified for which cost center it is being obtained. The tool management cost centers must be compared with those in the PPS system .

Movement data (logistics) of the tools

The logistics involved with the stocks, storage areas and procurement of tools. Within logistics, a distinction is made between the individual components and the complete tools assembled from them. For the components themselves, a distinction is made between the internal flow of materials and procurement from external suppliers ( warehousing ).

Storage of components

Tool components in stock

The logistics of the components primarily includes inventory management , planning of requirements and monitoring of the minimum inventory . When the minimum stock is reached, the tool management triggers a procurement process that is processed by purchasing with the ERP system . The tool management logistics has an operation that is tailored to the environment in which it is used and suitable interfaces to storage systems and other facilities within the company. A prerequisite for coordinated warehousing of the components is a central organization of the tools, in which all components of a production unit are stored in only one place, if possible, and every removal is reliably booked.

Internal logistics of the components

When it comes to in-house logistics, what is of particular interest is the location of the component being sought and the cost center at which it was used. Only the wearing parts (cutting edges) are consumed, the other components (base body, cutting devices) are simply moved between the warehouse, tool dispenser and machines. The booking of the components to the individual cost centers and locations takes place at the same time as the removal / storage in the warehouse. The provision of tools and resources is triggered with a production order , which refers to a tool list in the master data, in which all required components are listed. Before being used on the machine, the components are assembled into complete tools according to the information in the tool list. When planning the production orders, a check is made for each component to determine whether the available stock is sufficient to equip the machines.

In-house logistics of the complete tools

Complete tools on the machine

The complete tools are built from components and are usually dismantled again into the individual parts after use. Several copies of a complete tool can be assembled at the same time , provided that the components are available in sufficient numbers. The logistics of the complete tools relates to the condition and location of the specimens.

The complete tool copies can typically be in three different states:

  • Not yet assembled (the components are available as individual parts)
  • Assembled in interim storage (e.g. on a shelf)
  • Assembled on the CNC machine

When planning a production order, the complete tools required for the operation are known from the associated tool list. It is also known which complete tools are on the CNC machine intended for processing. The complete tools required but not yet available on the machine are printed out in a net loading list. They either have to be reassembled or removed from the interim storage facility. With a coordinated logistics of the complete tools, the effort for the provision of the tools and the changing in the machine is reduced.

Integration of tool data

The purpose of tool management is to ensure an efficient and error-free order flow in production. Existing knowledge is made generally available and the specifications recorded in the master data are observed. In order for this to be possible, the information for the various tasks must be available at the respective workstations. The integration of the tool data enables other applications to use the tool data that is maintained with the tool management. These applications either access the tool management database directly or the data is exchanged via interfaces. Especially in CNC production , where several people are involved in the production process, the integration avoids errors, delays and multiple data acquisition. The following is a description of how some of the most important applications relate to tool management.

PPS

Integration with the PPS system

In the PPS system , the work plan is saved for each component , which contains the description of the work processes and the list of the required resources . The resources are described with the tool management, because they cannot be sufficiently accommodated in the PPS system. If a component is to be manufactured, a production order containing the work plan is created with the PPS system. The required resources such as drawings, NC programs, tool lists and instructions are retrieved from the tool management in production. The integration means that an interface ensures that the information is actually available in the tool management if it is referred to by the PPS system in one work step. Systematic numbering of documents and equipment is a prerequisite for integration.

ERP (purchasing)

The ERP system plans raw materials, consumables and other resources. It is closely linked to the PPS system and takes on the tasks of materials management and logistics . In relation to the tools, this concerns the wearing parts (cutting parts) that are procured when the minimum stock is reached.

If the inventory of the components is managed with the tool management, orders are not sent to the supplier, but purchase requisitions are transmitted to the ERP system, which takes over the actual order. The prerequisite is that the articles are recorded with the same number in both systems. With the integration, all internal warehouse movements of the tool components can also be transferred to the ERP system for cost accounting.

CAM

The machining commands (NC program) for the CNC machines are created with the CAM system . The geometry, designation and cutting values ​​of the required complete tools are taken directly from the tool management. This ensures that all tools used are documented and correspond to the reality in the workshop. All tools used in an NC program are automatically saved from the CAM system as a tool list in the tool management. As a result, when preparing the work step, it is known how which tools must be set up and used.

Storage systems

In addition to conventional tool cabinets, storage systems are often used that provide the operator with the shelf with the desired article. The relationship between the article number and the storage location is saved in the tool management. When booking a tool removal in the logistics area of ​​the tool management, the storage system is activated automatically. Alternatively, the allocation of the storage locations can be configured in the storage system. The removal is then carried out on the storage system and the inventory change is transmitted to the tool management.

Preset

The CNC machine needs the exact dimensions of the tools to position them during machining. When inserting the complete tools into the machine, their length and diameter must therefore be entered. These tool settings can be measured with an external presetting device. Convenient presetting devices take over the setpoints, designations and tolerances from the tool management and transfer the measured actual values ​​directly to the control of the CNC machine. The integration of the tool management with the presetting devices takes place in the exchange format of the respective device manufacturer and also includes the graphics and information on the measurement method.

Tool catalogs

In order to reduce the effort of the initial recording of the components in the tool management, the tool manufacturers provide data and graphics in a suitably prepared form. The DIN 4000 and ISO 13399 exchange formats are currently used for the technical data of the tools. If necessary, the 2D graphics are provided in accordance with the DIN standard. STL and STEP formats are usually offered for 3D graphics and the axis position is selected according to the use on the machine. In addition, the tool data from many manufacturers is available in cross-manufacturer portals such as ToolsUnited, which enable exports that match the tool management system.

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