QUICK, EASY AND AFFORDABLE MEASUREMENT OF EXTERNAL AND INTERNAL
THREAD PITCH DIAMETER – ALSO AT THE MACHINE

Thread Pitch Diameter Measurement
d2 & D2
60º M, MF, UNC, UNF, UNEF, UNS,
55º Whitworth, G, BSP, R, Rc, BSPT, 60º NPS,
NPT, 30º Tr, Rd, 29º ACME, Stub Acme,
80º Pg, Buttress (all types), API, etc.

Video: Thread Pitch Diameter Measurement External & Internal

FMS caliper and thread inserts

Inserts 22B for P 2-4mm 13-6 TPI

Inserts 21B for P 2-4mm 13-6 TPI

D2 Calibration

When asking for information or requesting a quote
the 3 most important facts are:

Thread type

External and/or internal thread

Thread pitch

THREAD INSPECTION OR MEASUREMENT?

By ”inspection” means checking threads with solid gauges and preferably with both Go and No-Go thread plug and ring gauges. This applies in most cases, to smaller diameter standard threads cut with taps or dies. Gauges for smaller standard threads are usually reasonably priced although, if gauges are for non standard threads or to be calibrated regularly, cost increases.

Measuring threads is common sense especially when setting up the machine. Making a mistake in expensive items is costly and certainly cause for concern if it is a customer that finds a fault. When measuring always measure d or D1 and preferably pitch diameter. If the pitch diameter is close to the middle of the tolerance then inspection probably doesn’t need to be as often and with mass production SPC will show how much variation there in fact is within the tolerance by the process. There will almost certainly be much less wear on solid gauges by staying away from tolerance limits.

The major diameter (d) of an external thread must not be less than the minimum of the tolerance and the minor (bore) diameter (D1) of an internal thread must not be more than the maximum of the tolerance. Both these measurements are very easy to do and a stripped (weakened) thread could be a disaster.

Measure internal thread pitch diameter

 Measure metric and UN thread pitch diameter

Measure taper thread pitch diameter

 Measure taper pipe threads

Measure ACME Tr Trapezoid threads

 Digital caliper accessories

 Buttress thread measurement inserts

ACME thread measurement inserts

 TR Trapezoidal thread measurement inserts

 Thread information and pitch diameter tolerances

Thread measuring wires alternative

 Thread micrometer alternative

Innengewindesteigungsdurchmesser messen

 Messung des Gewindesteigungsdurchmessers

Mesurer le diamètre du pas de filetage interne

 Mida el diámetro del paso de la rosca interna

 la medida diámetro de paso de rosca

 Misurare il diametro primitivo della filettatura interna

Måle indvendig og udvendig gevind delediameter

Cèliáng nèi luówén zhōng jìng

Außen-und Innen Flankendurchmesser messen

Kegelgewinde messen

 Mesurer le diamètre du pas de filetage

mesurer les filetages coniques

Medir el diámetro del paso de la rosca

Misurare il diametro del passo del filo

zmierzyć średnicę skoku gwintu

Thread pitch diameter measurement

How to measure internal threads

Digital caliper measurement accuracy