Use this guide to understand the size, application, hand, pitch and thread form shown in threading insert codes.

Reading an Insert Code

Example: 16ER1.5ISO

Code	Meaning
16	Insert size
E	External threading; I indicates internal threading
R	Right-hand insert; L indicates left-hand insert
1.5	Thread pitch: 1.5 mm
ISO	ISO metric thread form

Insert Sizes

L identifies the insert size shown in the diagram. D is the inscribed circle diameter, expressed in inches.

L (mm)	D (in)
8	3/16
11	1/4
16	3/8
22	1/2
27	5/8

Pitch and Profile Types

Full-profile inserts are designed for a specific thread pitch and form. Partial-profile inserts cover a range of pitches.

Metric pitch is expressed in millimetres. TPI means threads per inch.

The following ranges are listed in this catalog. Check the individual product specifications when selecting an insert.

Profile	Code	Pitch (mm)	TPI
Full profile	–	0.5–6.0	48–4
Partial profile	A	0.5–1.5	48–16
Partial profile	AG	0.5–3.0	48–8
Partial profile	G	1.75–3.0	14–8
Partial profile	N	3.5–5.0	7-5
Partial profile	Q	5.5–6.0	4.5-4

Pitch and Profile Types

Code	Thread Form
60	60° partial-profile threads
55	55° partial-profile threads
ISO	ISO metric threads
UN	60° Unified threads
UNJ	60° Unified aerospace threads
W	55° Whitworth threads
NPT	60° American tapered pipe threads
NPTF	60° Dryseal tapered pipe threads
BSPT	55° British Standard Pipe Taper threads
ACME	29° Acme threads
TR	30° metric trapezoidal threads
ABUT	American buttress threads
RD	Round threads