® Spiral Mill - Thread Inserts BSPT Same insert for internal and external thread 1 2 Insert Size Fig. PitchTPI Ordering code Thread Size Toolholder H13 1 19 H13-19 BSPT 3/8 SRH13... H15 1 14 H15-14 BSPT 1/2 - 3/4 SRH15... H17 1 14 H17-14 BSPT 1/2 - 3/4 SRH17... H23 2 11 H23-11 BSPT ≥ 1" SRH23... H32 2 11 H32-11 BSPT Int. ≥ 11/8"Ext. ≥ 1" SRH32... H45 2 11 H45-11 BSPT Int. ≥ 13/4"Ext. ≥ 1" SRH45... H63 2 11 H63-11 BSPT Int. ≥ 21/2"Ext. ≥ 1" SRH63... NPT Same insert for internal and external thread 1 2 Insert Size Fig. PitchTPI Ordering code Thread Size Toolholder H13 1 18 H13-18 NPT 3/8 SRH13... H15 1 14 H15-14 NPT 1/2 - 3/4 SRH15... H17 1 14 H17-14 NPT 1/2 - 3/4 SRH17... H23 2 11.5 H23-11.5 NPT 1"-2" SRH23... 14 H32-14 NPT Ext. 1/2" - 3/4" H32 2 11.5 H32-11.5 NPT Int. 11/4"-2"Ext. 1"- 2" SRH32... H45 2 11.5 H45-11.5 NPT Int. ≥ 2"Ext. ≥ 1" SRH45... 8 H45- 8 NPT ≥ 21/2" H63 2 11.58 H63-11.5 NPTH63- 8NPT Ext. 1-2"≥ 3" SRH63... B04-6