NILES-SIMMONS provides customised solutions for the machining of challenging parts across the entire engineering sector. One solution available in the UK through McDowell Machining Technologies is the multi-functional TurnMill MC-series.
One application implemented by NILES-SIMMONS involved a bespoke concept on an N30MC TurnMill machining centre for the machining of valve parts for the oil and gas industry. Featuring external, internal and face machining, the machine with a distance between centres of 4.5m was equipped with a second slide for long tools and an additional long tool magazine.
With a part length of 1.3m and diameter of 315mm, it was clad in inconel 625. The material that required a surface finish of Ra0.2 wasn’t the only challenge. All the processes needed to be undertaken behind a ’closed-door’.
Undertaking turning, milling, drilling, gun drilling, finish-boring, reaming, thread turning and burnishing with a diamond-burnishing tool, particular attention was paid to chip control with the use of high-pressure coolant.
For internal machining, NILES-SIMMONS worked with Sandvik Coromant using the 100mm diameter Silent Tools™ Plus boring bar. With this bar, it is possible to monitor ‘in-cut’ performance in real-time which contributed to the security of the closed-door-machining process. The ‘smart’ boring bar provides the operator with ‘live’ feedback to monitor the temperature, displacement, insert wear or breakage and vibration. This allows the cutting conditions to be checked, evaluated and documented during the machining process – essential for machining large components behind ‘closed doors’.
This data is used to analyse and monitor performance and optimise the process whilst adding process security to allow the machine to stay in a stable cutting condition until the insert approaches its end of life.
When machining the internally clad components, the process security provided by the Silent Tools™ Plus means the machine, the part and tools are protected from damage – giving operators confidence in the process. Using adaptive control technologies to optimise cutting conditions, the process reliability and machining times were improved with tool life extended by more than 30 minutes. The adaptive control technology optimises the machining conditions by evaluating the level of vibration and axial loads to automatically adjust the parameters to maintain precision, finishes and component quality. These indicators enable the operator to better understand and evaluate insert tool life. The benefit is the accurate prediction of insert failure to maximise tool life and avoid costly tool breakages. In this case, the tool magazine capacity had to hold more than 400 tools with different connections as well as 15 positions for long tools in a dedicated magazine. In ‘closed door’ environments on large machine tools where the operator cannot visually gauge the changing surface finishes, vibration and chip formation, the Silent Tools™ Plus provides peace of mind, confidence and control over the entire process.
With the support of Mastercam software, Dynamic Turning was applied to optimise chip formation and control deflection forces. The clamping condition of the bar is also extremely important. For this, NILES-SIMMONS used their long tool cassettes, specifically designed to deliver rigid set-ups, clamping directly to the machine’s second slide (X2 & Z2) dedicated in this case, to long tools.
The process was finalised with face machining, drilling, tapping, countersinking and then gun drilling a 6.35mm diameter hole through a length of 1.3m in seven steps. This included a deep hole drilling process of 205XD.
The fully automated process also involved a highly advanced level of process automation features that enable closed-door machining without operator intervention. These features include automatic change of all tools and boring bars, in-process and dynamic measurement of the internal and external machined areas, including runouts, achieved surface roughness, automatic detection of the welded inconel layer with non-contact scanning for an optimised cycle time. It also incorporated intelligent operator guidance using an additional monitor regarding premature tool change, media filling, chip disposal and further predictive process measures.
This application underlines NILES-SIMMONS’ expertise in the field of customised machining solutions for highly complex parts and projects. The interaction of a highly developed machine with all the necessary and suitable process automation procedures, an efficient machining and tooling strategy as well as individual adaptations to the respective customer requirements is the strength of NILES-SIMMONS and McDowell Machining Technologies.
To learn more about the smart bar capability integration on NILES-SIMMONS’ Machines visit them at MACH on stand 17-110 where McDowell Machining Technologies will exhibit the part and bar set up with all the in-depth process information.
