TopThread ™
Catalogue Numbering System
TopThread
Insert Identifi cation System
NDC38RDR75
N D C 3 8RD R 75
Type
of Insert Insert Additional
Information Insert
Size Industry Thread
Identifi cation Hand
of Insert Defi nition
of Insert
Indicates API or
drilling industry
form designation
(e.g., 10RD,
8RD, .038)
or
controlled root
radius threading
inserts indicate the
root radius in 0,025
increments (NJ,
NJF, NJP, NJK)
or
M indicates metric
ISO thread R — Right Hand
N — TopThread ™
B — Buttress
F — Fine pitch
S — Stub Acme
C — Cresting
P — Positive rake
K — Fine pitch, positive
T
Additional
Information
L — Left Hand
• Threads per inch
or pitch (for metric)
• “A” or “B” type
Buttress insert
• Taper per foot —
API threads
A — Acme
TopThread insert dimensions
D — API or NPT
T — 60° V thread
W — 55° V Whitworth
T mm mm 1 2,54 2,54 2 5,56 3,81 3 8,74 4,95 E — External thread (used only if
internal and external thread
forms are different)
4 11,51 6,48 M — Multiple tooth
5 17,48 9,65 6 11,51 9,73 8 7,93 11,13
NJF
NDC-V-M
I — Internal thread
K — Standard chip control
C — Coarse pitch
NTC
D — Dryseal
NA
F10
NT
NT-K
widia.com
J — UNJ thread
A insert size