THREAD MILLS - NPT - STRAIGHT FLUTE

Transcription

1 THRED MILL NPT PECILTY PORT - CVITY INDEXLE INGLE POINT THRED MILL - NPT - TRIGHT FLUTE OLID CRIDE (NTIONL PIPE TPER) THRED / PITCH THRED / PITCH TRIGHT FLUTE - NPT UNCOTED LTiN+ 1/16, 1/ TM218-27NPTF TM218-27NPTF- 1/ TM280-27NPTF TM280-27NPTF- 1/4, 3/ TM330-18NPTF TM330-18NPTF- 1/4, 3/ TM382-18NPTF TM382-18NPTF- 1/2, 3/ TM430-14NPTF TM430-14NPTF- 1 to 2-11½ TM NPTF TM NPTF- 2½ up TM650-8NPTF TM650-8NPTF- UNCOTED LTiN+ 1/16, 1/ TM218-27NPT TM218-27NPT- 1/ TM280-27NPT TM280-27NPT- 1/4, 3/ TM330-18NPT TM330-18NPT- 1/4, 3/ TM382-18NPT TM382-18NPT- 1/2, 3/ TM430-14NPT TM430-14NPT- 1 to 2-11½ TM NPT TM NPT- 2½ up TM650-8NPT TM650-8NPT- For increased performance, use with tapered pipe reamer on page 114. MIN IN THRED/ PITCH Taper "" Coolant hole to each flute Made with premium submicron grade carbide LTiN+ coated for higher cutting speed COOLNT THROUGH TRIGHT FLUTE - NPT "" "" Coolant to each flute Cuts internal or external threads UNCOTED TRIGHT FLUTE - DRYEL - NPTF LTiN+ coating for improved surface finish Polished flute face for optimum performance ll NPT thread mills are crest cutting (full profile) COTED 1/16, 1/ TMC218-27NPT TMC218-27NPT- 1/4, 3/ TMC330-18NPT TMC330-18NPT- 1/2, 3/ TMC430-14NPT TMC430-14NPT- 1 to 2-11½ TMC NPT TMC NPT- 20 cientific Cutting Tools, Inc.

2 THRED MILL - NPT - TRIGHT FLUTE TGGERED TOOTH - OLID CRIDE (NTIONL PIPE TPER) THRED / PITCH TRIGHT FLUTE - TGGERED TOOTH - NPT For increased performance, use with tapered pipe reamer on page 114. taggered tooth design reduces tool pressure LTiN+ coating extends tool life Tool is steel shank with a solid carbide head Tool is carbide tipped with coolant hole to each flute Made from premium submicron carbide LTiN+ coated tool for higher cutting speed TRIGHT FLUTE - TGGERED TOOTH- DRYEL - NPTF UNCOTED LTiN+ 1/16, 1/ TM220-27NPT TM220-27NPT- 1/ TM275-27NPT TM275-27NPT- 1/4, 3/ TM335-18NPT TM335-18NPT- 1/4, 3/ TM387-18NPT TM387-18NPT- 1/2, 3/ TM435-14NPT TM435-14NPT- 1/2, 3/ TM440-14NPT TM440-14NPT- 1¼ to 2-11½ TM NPT TM NPT- THRED / PITCH UNCOTED LTiN+ 1/16, 1/ TM220-27NPTF TM220-27NPTF- 1/ TM275-27NPTF TM275-27NPTF- 1/4, 3/ TM335-18NPTF TM335-18NPTF- 1/4, 3/ TM387-18NPTF TM387-18NPTF- 1/2, 3/ TM435-14NPTF TM435-14NPTF- 1/2, 3/ TM440-14NPTF TM440-14NPTF- 1¼ to 2-11½ TM NPTF TM NPTF- ll NPT thread mills are crest cutting (full profile) Tool is steel shank with a solid carbide head Tool is carbide tipped with coolant hole to each flute THRED MILL NPT INGLE POINT INDEXLE PORT - CVITY PECILTY cientific Cutting Tools, Inc. 21

3 THRED MILL - NPT - HELICL - CRIDE (NTIONL PIPE TPER) THRED MILL NPT PECILTY PORT - CVITY INDEXLE INGLE POINT THRED /PITCH THRED / PITCH "" UNCOTED LTiN+ 1/16,1/ TMX H TMX H 1/4,3/ TMX H TMX H 1/2,3/ TMX H TMX H 1" to 2" TMX H TMX H UNCOTED LTiN+ 1/16,1/ TM218-27NPT-H TM218-27NPT-H 1/ TM280-27NPT-H TM280-27NPT-H 1/4, 3/ TM330-18NPT-H TM330-18NPT-H 1/4, 3/ TM382-18NPT-H TM382-18NPT-H 1/2, 3/ TM430-14NPT-H TM430-14NPT-H THRED / PITCH 15 HELICL FLUTE- NPT 30 HELICL FLUTE - NPT 30 HELICL FLUTE - NPTF - DRYEL Made with premium submicron grade carbide LTiN+ coating for improved surface finish For increased performance, use with tapered pipe reamer on page 114. LTiN+ coating extends tool life Helical flute for reduce side cutting pressure For increased performance, use with tapered pipe reamer on page 114. Polished flute face for optimum performance LTiN+ coated tool for higher cutting speed UNCOTED LTiN+ 1/16, 1/ TM218-27NPTF-H TM218-27NPTF-H 1/ TM280-27NPTF-H TM280-27NPTF-H 1/4, 3/ TM330-18NPTF-H TM330-18NPTF-H 1/4, 3/ TM382-18NPTF-H TM382-18NPTF-H 1/2, 3/ TM430-14NPTF-H TM430-14NPTF-H ll NPT thread mills are crest cutting (full profile) 22 cientific Cutting Tools, Inc.

4 THRED MILL FEED ND PEED CHRT THRED MILL TECH INFO MTERIL H/Rc PEED FM* UNCOTED PEED FM LTiN+ FEED ( INCHE PER TOOTH) DIMETER CT IRON 160 H CRON TEEL 18 Rc LLOY TEEL 20 Rc TEEL 20 Rc TINLE TEEL 150 H TINLE TEEL 195 H HIGH TEMP LLOY (Ni & Co E) 20 Rc TITNIUM 25 Rc HET TRETED LLOY (38-45Rc) 40 Rc LUMINUM 100 H R, ZINC 80 H *FM = urface Feet per Minute Parameters are a starting point based on machinability rating at hardness listed. Check machinability rating of the material to be machined and adjust accordingly. 40 cientific Cutting Tools, Inc.

5 THRED MILL FEED ND PEED PPLICTION THRED MILL TECH INFO It may be necessary to use more radial depth passes than shown on the chart (p.40) when cutting an unfavorable length-to-diameter ratio, coarse pitches, or hard materials. When cutting a thread with two passes, cut approximately 65% of the thread on the first pass and 35 percent on the finish pass. For three passes, use a 50/30/20 ratio. For four passes, use a 40/27/20/13 ratio. The idea is to equalize the side cutting pressure. Thread mills can sometimes be used to cut multiple start threads. Call engineering for assistance. Thread mills can be cut off for shorter thread depths or necked back for deeper thread depths. Call for price and delivery. In order to apply the Feed and peed chart appropriately, it is necessary to understand that machining centers will apply the feed rate at the centerline of the spindle. It is correct to use a normal calculation and the following Feed & peed Chart when cutting in a straight line; however, it is incorrect when cutting an internal thread. Therefore, the feed rate must be recalculated. The following is an example of how to apply the feed rate correctly: The tool is a TM cutting a 3/8-24 thread in stainless steel. The outside diameter of the tool is The surface foot per minute (FM) is 150. The chip per tooth ia The tool has four flutes. The revolutions per minute (RPM) equal the FM x 3.82 divided by the outside diameter of the tool. In this example: (150 x 3.82) / 0.290, which equals 1975 RPM. The RPM x feed (chip per tooth) x the number of flutes equals the Non-djusted Feed Rate or NFR. In this example: 1975 x x 4 = 7.9 NFR The major diameter of the thread is We will call this D. The outside diameter of the tool is We will call this d. We will call the djusted Feed Rate the FR. The formula for the FR for internal interpolation is FR = NFR x (D-d) D In this example: FR = 7.9 x ( ) Therefore, the djusted Feed Rate equals This is the feed rate that will equal chip per tooth in the above example. This is the feed rate that must be used in the CNC program. cientific Cutting Tools, Inc. 41

6 THRED MILL TROULEHOOTING THRED MILL TECH INFO PROLEM CUE OLUTION TPERED THREDED HOLE PREURE Reduce the chip load and/or make more radial passes. NO-GO GGE GOE & GO GGE DOE NOT GO THRED OVERCUTTING Use a tool of smaller diameter with correct pitch. Make sure helical "ramp in" is used. TEETH RE CHIPPING PREURE UILT-UP EDGE Reduce feed rate per tooth. Use a coated tool to help reduce built-up edge. RPID WER RUING NOT CUTTING Increase chip load per tooth. TEETH RE URNING TOO MUCH HET Reduce speed. Use a coated tool. Increase coolant. REK TOO MUCH PREURE Helical "arc in" must be used. Reduce feed rate and/or use more radial passes. djusted Feed Rate (FR) must be used. (ee Thread Mill Feed and peed Chart) Thread milling tools form a thread using a motion referred to as helical interpolation. This process involves the machine simultaneously moving all three axes. The resulting motions are circular and axial. The X and Y axes move in a circular manner and the Z axis in an axial direction per 360 at a distance equal to the pitch of the thread being machined. The tool should "ramp in" over 90 in order to avoid breakage. This must be a helical move. Move "Z" axially by pitch 4 since 90 is ottom-to-top climb cutting machining is recommended when machining a right-hand thread. This will avoid re-cutting any chips. For left hand threading, a top-to-bottom machining with a right-hand helical tool is the preferred method. Refer to troubleshooting chart above for solutions to potential thread milling problems. 42 cientific Cutting Tools, Inc.