Grooving and Parting Off Q&A
- May 12, 2017
Grooving and parting off are universal metal removal processes used by many manufacturers. While a common metalworking processes, with ongoing technology developments, Shop Metalworking Technology thought it would be a good idea to approach a cutting tool manufacturer with expertise in grooving and parting off and gain some insights to share with our readers.
Below is information provided by sales engineers from Horn USA. Participants in the Q&A include: Tom Guzik, Russ Kitzke, Scott Nelson,
Ryan Schaefer, Brian Sedesky and Mike Smoody.
What, in your opinion, has been the greatest technology development in grooving and parting off tools?
The greatest technological development in grooving and parting off tools is the development of new coatings, cutting geometries, and applying coolant directly to the cutting zone. Horn is constantly looking for ways to decrease the cost per piece for the customer. This involves continuous research and development to create new, or improve upon current geometries and coatings to transfer heat from the cutting edge of the tool and into the chip. Proper chip control and formation can greatly increase tool performance and minimize wear on the cutting edge of the tool.
Can you provide advice and best practices for the following grooving and parting off processes?
Internal grooving (including deep grooving)
Chip evacuation and proper coolant supply are extremely important to internal grooving processes. Selecting the proper chip geometry and coating combination is crucial to a repeatable and stable process for all grooving applications. Coolant through options on tools are a good way to help ensure the cutting edge of the tool has lubrication to aid in heat transfer from the insert to the chip.
Ensuring you are using the most effective grooving process will provide the most benefits. Many of our grooving tools have multi- directional capabilities. This allows for a “plunge turn” process keeping the tool engaged in the cut, thus reducing cycle time.
The rigidity and stability of your tool holder set up is extremely important when it comes to parting off as your tool is often times going very deep into the material. Controlling surface footage (SFM) and feed rate at near zero diameter is very important to maintaining good tool life. This is a harsh environment as you are not producing enough heat to plasticize the material you are cutting. Catastrophic tool failure is common in part off applications if these conditions are not controlled.
New coating and substrate combinations are continually increasing heat resistance and lubricity. This ever advancing technology along with complex chip geometries and coolant-through holders and inserts allow for increased cutting parameters, thus reducing cycle time. Horn has come out with the EG35 and EG55 coatings that have shown increased tool life in steels and stainless steels.
What advice would you give for manufacturers who are considering their options when it comes to grooving? For example, when should an operator consider plunge turning or ramping instead of grooving or vice versa?
We would consider groove turning when the width of the groove is more than three times the width of the insert that we would be using and the set-up is rigid. This will allow for better distribution of wear on all edges of the insert instead of just on the front face of the insert as would be the case in plunge grooving. We would consider plunge cutting when the width of the groove would require three or less roughing passes to complete, or if the machine/set-up is less rigid. Both options are most often going to be for roughing and will require a finishing pass.
What, in your opinion is the greatest factor that can improve the performance of a grooving or parting off insert?
The greatest factor is the rigidity of the machine setup and tool used, and limiting the time in cut to allow for longer service life of the tools.
How do you assess and determine the quality of your grooving and parting off tools?
We assess the quality of our tools from the feedback of customers and colleagues, as well as testing data.
What key guidelines do you suggest for selecting an insert for grooving and parting off?
We consider all aspects of the application. Material, workholding, rigidity, type of machine tool, capability of the machine tool, width of the insert, depth of cut, and type of coolant whether it be emulsion or oil. All of these factors contribute to the selection of the style, geometry, and grade of the insert.
How important is coolant in grooving and parting off processes and how have coolant delivery systems changed? Has this had an impact on how Horn designs and manufactures its grooving and parting off tools?
Coolant plays a very important role in grooving and parting off applications. It provides lubricity, cools the insert, and helps with chip evacuation.
Horn has developed various ways to deliver coolant to the cutting edge through our toolholders. Those options include through the top of the tool finger, from beneath the insert, through the insert itself, and from the side of the insert. These technologies combined with the increasing prevalence of high pressure coolant pumps on the machines provide incredible results.
How have digital manufacturing platforms (also known as Industry 4.0 and Industrial Internet of Things) impacted cutting tool developments?
Platforms such as Machining Cloud allow everyone access to an online catalog. More importantly this will also give them access to DXF or STP files which aid in programming and verifying toolpaths before ever hitting the shop floor.
How specifically have these changes impacted Horn, its product offerings and its services for customers?
These changes have forced Horn to stay on the cutting edge of technology by continuously working toward improvement in our products, processes, employees, and communication with our customers. SMT