A cable gland is a device that allows the user to pass a cable, wire or tube into an enclosure while providing strain relief and sealing out dust, dirt, and liquids. Mencom cable glands are mainly categorized by three major mounting thread sizes: NPT, PG, and Metric. The chart below explains technical terms related to the cable glands and illustrates differences between the threads.

1. THREAD types COMPARISON for CAble Glands
NPT
NPT Threads
metric PGvs vs
Basics of
Thread
GENDER
HANDEDNESS
DIAMETER
Internal
Thread
External
Thread
Depth
Minor
diameter
Pitch diameter
Major
diameter
Pitch
Crest
Root
Major diameter
Pitch diameter
Minor diameter
FemaleMale
Left-handRight-hand
DESIGN
ANGLE
PITCH/TPI
CREST/ROOT
Pitch
1”
Threads per Inch
Parallel
Thread
Angle
Flank
Taper Angle
Tapered
National Pipe Tapered
major diameter
in inches [mm]
Pitch
in inches [mm]
TPI
[Thread per inch]
1/16”-27 NPT
1/8”-27 NPT
1/4”-18 NPT
3/8”-18 NPT
1/2”-14 NPT
3/4”-14 NPT
1”-11 1⁄2 NPT
1.5”-11 1⁄2 NPT
1.25”-11 1⁄2 NPT
2”-11 1⁄2 NPT
0.313 [7.938]
0.405 [10.287]
0.54 [13.716]
0.675 [17.145]
0.84 [21.336]
1.05 [26.67]
1.315 [33.401]
1.9 [48.26]
1.66 [42.164]
2.375 [60.325]
0.037 [0.947]
0.037 [0.947]
0.056 [1.41]
0.056 [1.41]
0.071 [1.814]
0.071 [1.814]
0.087 [2.208]
0.087 [2.208]
0.087 [2.208]
0.087 [2.208]
27
27
18
18
14
14
11 1⁄2
11 1⁄2
11 1⁄2
11 1⁄2
Thread size
- Taper rate for all NPT threads is 1/16
- The flank angle is 60°
- The taper on NPT threads allows them
to form a seal when torqued as the
flanks of the threads compress against
each other, as opposed to straight
thread fittings
Nominal
Pipe Size
TPI
”- NPT
B
A
C
60°
1° 47’
A B C
Metric Threads
International Organization for Standardization (ISO)
major diameter
in inches [mm]
Pitch
in inches [mm]
fine Thread size
- The most commonly used thread type
in the world
- The flank angle is 60°
- Female and Male thread are both
parallel
Major
Diameter
M x Pitch
A B
M6 x 1.0
M8 x 1.25
M12 x 1.5
M16 X 1.5
M20 X 1.5
M25 X 1.5
M32 X 1.5
M40 X 1.5
M50 X 1.5
M63 X 1.5
0.24 [6]
0.31 [8]
0.47 [12]
0.63 [16]
0.79 [20]
0.98 [25]
1.26 [32]
1.57 [40]
1.97 [50]
2.48 [63]
0.04 [1.0]
0.05 [1.25]
0.059 [1.5]
0.059 [1.5]
0.059 [1.5]
0.059 [1.5]
0.059 [1.5]
0.059 [1.5]
0.059 [1.5]
0.059 [1.5]
0.251 [6.4]
0.33 [8.4]
0.492 [12.5]
0.63 [16]
0.79 [20]
0.98 [25]
1.26 [32]
1.57 [40]
1.97 [50]
2.48 [63]
Through Hole
in inches [mm]
C
B
A C
60°
PG Threads
Panzer-Gewinde (also Panzer-Rohr-Gewinde)
major diameter
in inches [mm]
Pitch
in inches [mm]
Thread size
- German thread type
- Depth of thread smaller than NPT or
Metric, but larger flank angle (80°)
- Female and Male thread are both
parallel
Nominal
Thread Size
PG
A B
PG 7
PG 9
PG 11
PG 13/13.5
PG 16
PG 21
PG 29
PG 36
PG 42
PG 48
0.49 [12.5]
0.60 [15.2]
0.73 [18.6]
0.80 [20.4]
0.89 [22.5]
1.11 [28.3]
1.46 [37]
1.85 [47]
2.13 [54]
2.39 [59.3]
0.05 [1.27]
0.056 [1.41]
0.056 [1.41]
0.056 [1.41]
0.056 [1.41]
0.062 [1.59]
0.062 [1.59]
0.062 [1.59]
0.062 [1.59]
0.062 [1.59]
0.50 [12.7]
0.606 [15.4]
0.74 [18.8]
0.8149 [20.7]
0.897 [22.8]
1.12 [28.6]
1.47 [37.4]
1.87 [47.5]
2.14 [54.5]
2.35 [59.8]
Through Hole
in inches [mm]
C
B
A C
80°
Mencom, the industry leader in Panel Interface Connectors, has well over 3,000 designs in
produc�on that provide safety, convenience and flexibility for programmers and
trouble-shooters. Also we have a team of engineers with decades of experience. Combined
with a progressive manufacturing facility, we are not only ready to provide a solu�on but
also able to assist challenging connec�vity issues from small changes to custom
termina�ons & assemblies with affordable costs and fast turnaround.
MENCOM.COM
For more information, visit
SOURCES
https://www.sealconusa.com/catalog/e-srf-cat/49-Technical-Info-Thread-NPT-Metric-PG-BSPP.pdf
https://www.teesing.com/files/en/brochures/Type-of-thread.pdf