ET/EDT Solid Carbide Thread Mills for High-Hardness Steels FEATURES Capable of thread milling of high-hardness steels of 45HRC or higher Tip shape reduces cutting resistance and suppresses tool bending Epoch D Thread Mill can perform drilling and threading simultaneously Advanced tool coatings provide improved cutting performance and extended tool life
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
ET/EDTSolid Carbide Thread Mills for High-Hardness Steels
FEATURES
Capable of thread milling of high-hardness steels of 45HRC or higher
Tip shape reduces cutting resistance and suppresses tool bending
Epoch D Thread Mill can perform drilling and threading simultaneously
Advanced tool coatings provide improved cutting performance and extended tool life
• No pilot hole needed. This single tool can perform both drilling and threading simultaneously.
• High-strength edge shape design suppresses edge tip breakage in severe machining environments including hardened steels.
• ATH Coating delivers improved hardness and oxidation resistance.
INTRODUCTION
The new EDT Series Thread Mill Series is designed to machine precision threads in a range of materials including hardened steels up to 66HRC. Our thread mills deliver improved cutting and chip removal, reducing the risk of the cutting tool breaking off inside of the hole.
Additionally, one thread mill can perform a variety of applications including right-hand thread milling, left-hand thread milling, and fine threading simply by changing the NC program. Cutting load is much smaller than conventional taps, and special toolholders are not needed.
1. Features of Epoch Thread Mill
• Tough and strong edge design for threading in hardened steels. • Tip shape reduces cutting resistance and suppresses tool bending. • Drastically reduces tool breakage • PN Coating provides excellent adhesion and wear resistance
FEATURES
3. New PVD Coating Technology
Advanced TH (ATH) Coating: With a hardness of 3800Hv and oxidation temperature of 1200°, our new ATH Coating enables longer life and higher efficiency when cutting high-hardness materials (55HRC or higher). Compared with our previous generation coating, double the tool life and more than double the machining efficiency can be achieved. The ATH Coating is ideal for both dry cutting and wet cutting in a variety of materials including cold-worked die steel, HSS, tool steel, composite materials, carbide alloys and more.
Cross-section photograph of ATH coating layer structure
■ Conventional Coating ■ ATH Coating for hard materialPat.No.3934136
Reduces the risk of tool breaking By using a tool with a diameter smaller than the inside diameter of the thread, cutting chips are smaller and chip evacuation is improved. The risk of the tool breaking off inside the hole is reduced as a result.
One tool – various types of thread milling Right-hand, left-hand and fine thread milling can be performed by just changing the NC program. The nominal diameters of the coarse threads and fine threads that can be processed with the same tool are different. (Example: For ET-1.25-16-PN, coarse thread is M8 × P1.25 and fine thread is M10 × P1.25).
Cutting conditions can be freely set Unlike when using taps, synchronizing the rotation and feed rates is not necessary. Thread mills can be used in the same manner as end mills and cutting conditions can be set according to the processing environment.
Usable on a variety of machines Thread mills can be used even on machines with lower-powered spindles. In addition, special tooling such as tapping holders are not necessary.
Provides good finished surfaces Interrupted cutting suppresses gouging to provide good finished surfaces.
Thread milling can be performed to the bottom of the hole Epoch Thread Mills are designed with no incomplete crests and Epoch D Thread Mills have only one incomplete crest, making them ideal for when you want to perform thread milling to the bottom of shallow holes.
1. Startup2. Position for starting point
of machining3. Entry (gradually cutting in)
4. Threading5. Release (gradually
detaching from cutting)6. Ending
Easily Create NC Programs Online Create cutting programs for the ET and EDT mills in our app at: http://www.mmc-hitachitool.co.jp/e/index.html
1 2 3 4 5 6
PN Coating: By optimizing the AI content, the multi-layer PN Coating exhibits both excellent heat-resistance and adhesion to the tool substrate. Combining of the AlCr coating layer with Si produces high hardness (3000HV) as well as good wear resistance. PN Coating provides extended cutting tool life in both wet and dry machining of materials including pre-hardened steel, carbon steel, alloy steel, stainless steel, H13, D2 and more.
Epoch D Thread Mill can perform boring simultaneously.
Left-hand cutting tool – Reverse spindle rotation should be used.
1. ET thread mills are only for threading the inside of holes.2. The above cutting conditions are for the nominal diameters stated in the table. Cutting conditions for other nominal diameters should be calculated taking into consideration
the Cutting Considerations (page 15).3. The machinery should be a machining center equipped with NC (numerical control) equipment having a helical interpolation function.4. The feed rate stated in the above conditions table is the feed rate at the tool center during tapping. In addition, the per-tooth feed rate is the numerical value at the cut-
ting point.5. Since there is a risk of cutting chips getting inside the machine, when using tools equipped with oil holes, be sure to use the oil holes.6. Use the appropriate coolant for the work material and machining shape.7. These conditions are for general guidance; in actual machining conditions adjust the parameters according to your actual machine conditions.
1. ET thread mills are only for threading the inside of holes.2. The above cutting conditions are for the nominal diameters stated in the table. Cutting conditions for other nominal diameters should be calculated taking into consideration
the Cutting Considerations (page 15).3. The machinery should be a machining center equipped with NC (numerical control) equipment having a helical interpolation function.4. The feed rate stated in the above conditions table is the feed rate at the tool center during tapping. In addition, the per-tooth feed rate is the numerical value at the cut-
ting point.5. Since there is a risk of cutting chips getting inside the machine, when using tools equipped with oil holes, be sure to use the oil holes.6. Use the appropriate coolant for the work material and machining shape.7. These conditions are for general guidance; in actual machining conditions adjust the parameters according to your actual machine conditions.
1. EDT thread mills are capable of simultaneous boring and threading.2. The above cutting conditions are for the nominal diameters stated in the table. Cutting conditions for other nominal diameters should be calculated taking into consideration
the Cutting Considerations (page 15).3. The machinery should be a machining center equipped with NC (numerical control) equipment having a helical interpolation function.4. The feed rate stated in the above conditions table is the feed rate at the tool center during tapping. In addition, the per-tooth feed rate is the numerical value at the cut-
ting point.5. Since there is a risk of cutting chips getting inside the machine, when using tools equipped with oil holes, be sure to use the oil holes.6. Use the appropriate coolant for the work material and machining shape.7. These conditions are for general guidance; in actual machining conditions adjust the parameters according to your actual machine conditions.
1. EDT thread mills are capable of simultaneous boring and threading.2. The above cutting conditions are for the nominal diameters stated in the table. Cutting conditions for other nominal diameters should be calculated taking into consideration
the Cutting Considerations (page 15).3. The machinery should be a machining center equipped with NC (numerical control) equipment having a helical interpolation function.4. The feed rate stated in the above conditions table is the feed rate at the tool center during tapping. In addition, the per-tooth feed rate is the numerical value at the cut-
ting point.5. Since there is a risk of cutting chips getting inside the machine, when using tools equipped with oil holes, be sure to use the oil holes.6. Use the appropriate coolant for the work material and machining shape.7. These conditions are for general guidance; in actual machining conditions adjust the parameters according to your actual machine conditions.
Dimensional Accuracy Worsens When Moving Toward the Bottom of the Hole (Deflection)
Regarding Tool Breakage
NC Program Created by Hitachi Tool’s NC Program Creation Software Doesn’t Work Properly
Regarding Upper Limit on Machinable Thread Diameters
Suitable tool diameter compensation should be performed according to the work material and tool wear condition. Also, please be careful not to forget to input the tool diameter compensation value into the machine.
For information about diameter correction, refer to the Cutting Considerations on page 15.
A characteristic of the thread milling method is that tool deflection increases as the tool progresses toward the bottom of the hole. It may be necessary to perform zero cutting in order to perform high-accuracy thread milling with low deflection.
As a countermeasure against tool breakage, performing processing with a reduced feed rate is effective. In addition, when processing with tool extended or when large rough cutting chips are produced, breakage due to chip clogging should be considered. In such cases, if processing is performed with a higher cutting speed, the cutting chips will be broken into smaller bits which may improve conditions.
Changes in cutting chip conditions due to different cutting speeds Simultaneous boring and thread milling (M8 × P1.25) of carbon steel)
There are differences in the programming code for the machine being used. Please contact the machine manufacturer for details.
Please note that since the Epoch D Thread Mill performs boring simultaneously, it cannot perform thread milling for diameters of more than 1.68 times the tool diameter Dc. There are no particular similar limitations on using the ET mill.
When performing thread milling by helical interpolation, the cutting point feed rate should be multiplied by a coefficient to determine the tool center feed rate. The equation for calculating the tool center feed rate is shown at right.
When performing thread milling by helical interpolation, it may be necessary to compensate for increased cutting resistance due to differences in work materials or tool wear condition. In the NC programs created using Hitachi Tool’s NC program creation software, tool diameter compensation is in radius designation format.
Correction example: Threading of hardened material (60HRC) (M8xP1.25)
Work material: D2 (60HRC) Tool: ET-1.25-20-PN Pilot Hole Dia: ø6.2 Pilot hole depth: ø6.8x25mm
Tool dia. correction value (mm) 3.09 3.08 3.06 3.04
• When using coolant, air blower is recommended. Water-soluble cutting fluids are suitable for some work materials or improving the grade of processed surfaces. Oil-based cutting fluids are not suitable because they degrade chip removal characteristics.
• The holder should grip the tool shank so that the holder does not block the hole. The shank projection amount is 1 to 2 times the shank diameter. The coolant nozzle should be positioned so that the coolant will reach the bottom of the hole. In addition, coolant pressure should be adjusted so that it removes cutting chips. If the setting is bad, cutting chip clogging may lead to flute tip damage or tool breakage.
• Since there is a risk of cutting chips getting inside the machine, when using tools equipped with oil holes, be sure to perform processing using the oil holes.