Общий каталог Yamawa 2021 - страница 692

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17. Taps for Pipe Threads Intro JIS Pipe Taps The pipe thread standard (JIS B 0202,0203) was revised in 1982 to meet ISO standard. In the same year, JIS B 4445 (straight pipe thread taps) SP and JIS B 4446 (taper pipe thread taps) were also revised. • A part of the pipe thread standard was revised in 1966 to meet ISO, but in the 1982 revision, the ISO standard was defined in the main book of JIS and the old 1966 standard was defined in JIS Appendix. For Pipe Threads specified in the main book of JIS and JIS Appendix, thread symbols are different but the nominal size 1/8 to 6 inch are same. In the 1998 revision, the contents of the main book of JIS and JIS Appendix are not changed. SL • ISO tap standard for pipe threads is different from the JIS tap standard in style, size and thread limit. Like the pipe thread standard, in JIS tap standards for pipe threads, style, size and thread limits of ISO standard are adopted in the main book of JIS and those of old JIS standard are in the JIS Appendix. For ISO standard (style and size), please refer to the next page. • Thread limits of Rp and G taps are the same as the ISO standard. The thread limit of Rc taps is the same as the JIS class 2 of PT taps shown in JIS Appendix because Rc is not specified in the ISO standard. Therefore, both Rc taps and PT taps can be used interchangeably. For the PO relation between thread limit of internal threads and tap thread limit, please refer to the table below. • Pipe Tap standard was revised in 1987. And tap designations shown in JIS Appendix were changed to PF taps for Parallel Pipe Thread, PT taps for Taper Pipe Thread, and PS taps for Parallel Pipe Thread. ST Symbol of Pipe threads Type Classification Standard JIS (ISO) JIS Appendix Internal Thread Rc PT Taper Thread External Thread R PT ROLL Taper Thread JIS B 0203-1982 Internal Thread Rp PS Parallel Thread External Thread - - G PF, A class Internal Thread - PF, B class CARBIDE Parallel Thread Parallel Thread JIS B 0202-1982 G, A class PF, A class Internal Thread G, B class PF, B class LONG Relation between classification/engagement of pipe threads and taps Kind of thread Classification Main usage Type Engagement pipe taps HAND Parallel Parallel internal thread PS TAPS PS D (Rp) D2 THL D1 Basic diameter position Internal threads EG (STI) Taper internal thread D D2 In connection of pipes, Taper PT D1 Taper pipe parts and fluid parts PT THL pipe they are used mainly (Rc) threads for the purpose of pressure type joints. Taper internal thread SPECIAL THREADS, D D2 D1 t GAUGES Pipe thread Taper a f S-PT External PT threads (R) Taper external thread THREAD MILLS d2 d1 d Internal PF Parallel internal thread threads (G) In connection of pipes, PF DIES D D2 Parallel pipe parts and fluid parts, D1 pipe they are used mainly threads for the purpose of mechanical type joints. d d2 Parallel external thread External PF d1 threads (G) CENTER DRILLS Technical info 693