Test Results

Roughing Ductile Iron


Romay NTK
Cost per Tool: $6.72 $8.13
Tool: CNMA 433 T7 CC-513 CNGA 433 T00820 SX8
Parts per Edge: 70 35

Cutting Conditions

Cutting Speed: 1600 SFM 1600 SFM
Feed: 0.014″ IPR 0.014″ IPR
Depth of Cut: 0.150″ DOC per side 0.150″ DOC per side


Annual Labor Savings: $21,300.00
Annual Hard Cost Savings: $20,320.00

Distributor Salesmen Report (names removed)

Distributor has history dating back to 2001 showing customer has used the NTK CNGA 433 GRADE SX8. It is used as a rough turn in the fabrication of hydraulic pump bodies. The insert was changed every 30-35 parts, this depending on the size of the block. The 30-35 pieces was a number decided upon by the customer’s engineers to keep the lathe running. 30-35 parts kept the customer in the realm of other tool changes, thus most inserts were changed at the same time.

This is the insert in the Lathe that was changed the most. The NTK insert could reach maybe 50 pieces, however customer thought that would generate less production, with the machine being shut down more often. We did test the NTK SX1 grade as well. We still were nowhere close to a 60 or 70 part tool change.

Testing of a competitor’s insert had to double tool life to stay within the realm of other tool changes. It took a couple different grades and hones, but Romay was successful. We ended up with a CNMA 433 T7 CC-513 Romay insert. We are reaching the next plateau of tool changes and have had no issues of premature failure that I am aware of.

Facing Cast Iron


Romay NTK
Toolholder: DSJNR 1.64D DSJNR 1.64D
Insert: SNMA 433 T7 SNGA 434 T0820
Insert Grade: CC-514 KY3500

Cutting Conditions

Cutting Speed: 1125 SFM 900 SFM
Feed: 0.012″ IPR 0.009″ IPR
Depth of Cut: 0.070″ DOC 0.070″ DOC


Time Per Part: 1:17 (minutes) including down time 1:37 (minutes)
Parts Per Edge: 120 60

Cost Svaings

Cost per Insert: $7 $12
Parts per Insert: 960 480
Cost per Part: $0.0073 $0.0250

Roughing Cast Iron

Operation: Turning & Facing
Material: Grey cast iron – heavy interruption
Hardness: 200 Bhn
Speed: 2200 SFPM
Feed: .012″ IPR
Depth-of-cut: .100″ DOC
Insert: CNGA 434 T7 CC-52-J Romay CNGA 434 T7 Toshiba FX-105
1st Edge: 40 25
2nd Edge: 40 25
3rd Edge: 40 25
4th Edge: 40 25

The Romay insert costs less and gave significantly better tool life.

Roughing Cast Iron

Operation: Turning Pulley’s
Material: 63000 Grey Cast Iron
Hardness: 187-241 Bhn
Insert: CNGA 432 T7 Romay CC-515 (SiN) CNMA 432 Mitsubishi UC-505 (coated carbide)
Roughing Speed: 3500 SFPM 1000 SFPM
Roughing Feed: .012″ IPR .016″ IPR
Roughing Depth-of-cut: .180″ DOC .180″ DOC
Insert: CNGA 432 T7 Romay CC-515 (SiN) CNGA 432 T7 Kennametal Kyon 3500 (SiN)
Finishing Speed: 4000 SFPM 2500 SFPM
Finishing Feed: .008″ IPR .008″ IPR
Finishing Depth-of-cut: .035″ DOC .035″ DOC
1st Edge: 180 40
2nd Edge: 170 35
3rd Edge 185 42
4th Edge: 182 41

Romay SiN significantly outperformed the Coated carbide in roughing and a competitors SiN in finishing, At a lower price.

Rough turning gray cast iron

Operation: Rough Turning
Material: Grey cast iron
Insert: CNGA 433 T7 Romay CC-513 CNGA 433 T Valenite Q65
Speed: 1500 SFPM 1500 SFPM
Feed: .018″ IPR .018″ IPR
Depth-of-cut: .060″-.080″ .060″-.080″
Tool Life: 319pcs/edge 289pcs/edge

Romay grade CC-513 increased tool life by 10% over Valenite’s Q65 at a
significant cost savings per insert

Finishing Steel

Operation: O.D. Continuous Turning
Material: 4140 Steel
Insert: CNGA 432 T7 Romay CC-30 (black ceramic) CNGA 432 Ceratip CER II
Speed: 450 SFPM 450 SFPM
Feed: .005″ IPR .005″ IPR
Depth of cut: .010″ .010″
Length of cut: 4.5″ 4.5″

Romay grade CC-30 black ceramic equaled Ceratip’s CER II, but at a much lower cost per insert.

Hard-turning steel

Operation: Turning
Material: S-7 die steel
Hardness: HrC 58
Speed: 400 SFPM
Feed: .003″ IPR
Depth-of-cut: .010″ DOC
Insert: CNGA 432 T2 CC-30-C
CNGA 432 T00625 A66N
Parts Per Edge: 28 23
Reason for
Flank wear – normal Chipping – !

Romay CC-30-C cost less and lasted longer than a competitors coated ceramic, Kyocera A66N.

Finish Turn of 440-C Stainless Steel

Ceramic Inserts Eliminate Grinding

Machine: Mazak Slant Turn 30 NC lathe.
Part: 440-C stainless steel, hardened to 52-56Rc
Rough-machined sleeve spacers made of 440-C stainless steel (hardened to 52-56 HRC) were being ground on both OD and ID to achieve a surface finish of 32 rms. The sleeves were 31/4″ in diameter and length, with walls .383″ thick. The grinding operation took 2.6hrs. per piece, floor to floor.

When the finishing operation was moved to a Mazak Slant Turn 30 NC lathe tooled with CC-20 black ceramic inserts, size control was maintained, surface finish was improved, and there was significant savings in shop time.

Setup: Grinding Data: OD(turn) ID(bore)
Insert: CNG 434 CNGA
Grade: CC-20 CC-20
Workpiece Diameter: 3.267″ 2.5″
Depth of Cut: .0075″ .0055″
Feed Rate (IPR): .003″ .004″
Cutting Speed (SFM): 400 400
Length of Cut/Pass (inches): 2 ¼ 3 ¼
Time in Cut/Pass (minutes): 1:35 1:21
Pieces/Edge: 10 10
Finish: 32rms 11-12rms 11-12rms
Floor to Floor Time: 2.6hrs.                          15:00 minutes total

Savings (Machining Time):


Questions? Technical phone-support is available

Ask for  Dave Maynard @ 517-769-6662

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