Modification of the Clamping System on a CNC Machine

By mastering AAR-type tripods, they gained a competitive advantage. They began their own production of products and thus supplied the assembly cells in the company. In the mastering process, they successfully used existing machine equipment. The new clamping system enabled faster machining feeds, which allowed them to transition from the existing system of two cuts to machining with one cut during turning. ** The result of machining with only one cut was a reduction in the machining cycle time by 15 seconds per piece.** Thus, they produced a greater number of pieces and increased productivity by 25%. With stable clamping, they reduced the number of rejected pieces. ** Thus, replacements, tool adjustments, or disassembly and assembly of working heads were not necessary.** When changing the type, we did not face tool adjustments or major machine settings.

Problem

By mastering AAR-type tripods, they gained a competitive advantage.

Solution and Method

They began their own production of products and thus supplied the assembly cells in the company. In the mastering process, they successfully used existing machine equipment. They upgraded the existing working head with new clamping tooling. Due to problems they had with reduced productivity, increased scrap, and consequently an unstable process, they ordered a new working head. ** With a stronger structural design of the clamping head, they ensured precise clamping of the workpiece.** The implementation of the new working head was successfully carried out on the machine with the team that had been assembled.

Results

The new clamping system enabled faster machining feeds, which allowed them to transition from the existing system of two cuts to machining with one cut during turning. The result of machining with only one cut was a reduction in the machining cycle time by 15 seconds per piece. Thus, they produced a greater number of pieces and increased productivity by 25%. With stable clamping, they reduced the number of rejected pieces. ** Thus, replacements, tool adjustments, or disassembly and assembly of working heads were not necessary.** When changing the type, we did not face tool adjustments or major machine settings.

The changeover time was thus reduced from the existing state to the new system by a tenfold value of changeover time. The faster changeover time was achieved due to simplified disassembly and assembly of the clamping tooling on the new system. After tool changeover, adjustments and other corrections were not necessary, so the changeover was carried out quickly. The changeover was also reduced with pre-prepared tooling and necessary machine corrections. During production, we no longer faced incorrect piece position during turning, poor surface quality, and unstable leg diameter dimension.

With all this, scrap on the machine was reduced by 0.5% relative to the number of well-manufactured pieces. Additionally, they also reduced tool consumption on the new system, which was the result of precise piece clamping and stable holding during machining. With the existing system, they had increased tool consumption due to cutting insert breakage and clamping tool replacement due to problems during turning.

Now the piece holding is stable and the cutting insert maintains the expected durability. The new working head also ensures effective control of piece rotation. With this, they reduced collisions with the turning tool, which were the result of incorrectly oriented workpieces. To ensure the 120° leg position during machining, the new tooling enables adjustment via two screws, with which we shift the leg to the desired position. This solution is the most effective for the problems they faced with the existing system. ** Based on experience with existing working heads, they faced similar problems.** However, upgrades with such adjustable tooling on existing systems were not permitted by the construction itself.

In the coming years, the quantities of AAR-type pieces are increasing, so they are already prepared for the implementation of the next working head on the next machine. The only disadvantage of the working head is that it is a dedicated head only for the production of AAR-type tripods. In the event that it is necessary to increase capacities on the GI generation of tripods, we must carry out a working head replacement on the existing system.

Therefore, we plan quantities precisely through planning so that the machines are fully occupied or the machine utilisation is greatest. The purchase of a new working head was a completely correct decision. Although we could have operated with the existing working head, due to the unstable AAR-type production process, we would have caused significant costs. Nevertheless, by modifying the existing working head system, they gained an alternative that can benefit us. Since we can produce two different types of products on the existing system, the head is so flexible that we can produce smaller quantities on this tooling.

The next project of assembling the working head for the AAR type will be much easier, as they compiled a project folder in which all records are stored. We also have NC and PLC programme archives created. They mastered a new product type, became competitive, increased productivity and machine capacity. In terms of cost, the purchase of tooling and the new working head is amortised within one year based on the profit we generate with our own production. The implementation of the head on the machine itself was also an additional saving, as they carried out the project completely independently. ** With the new working head, they stabilised the process and reduced scrap.** They achieved all the set project points and successfully completed their goals.

For the success of the project, in addition to technical knowledge, the following factors are important: connectivity, coordination, organisation, obedience, will, motivation, flexibility, and dedication of the team to the set project. All of this was part of their team, and the next project for the implementation of the new working head is a guide to successfully complete the project on the next machine.