Metric Trapezoidal Thread (Tr)
Metric Trapezoidal Thread Profile
- Thread form angle : 30°
- P : Pitch
- H : Height of fundamental triangle
- H0 : Height of thread on basic profile
- h3 : Height of external thread on design profile
- H4 : Height of internal thread on design profile
- ac : Clearance on the crest
- D : Major diameter of internal thread
- D1 : Minor diameter of internal thread
- D2 : Pitch diameter of internal thread
- D4 : Minor diameter of internal thread on design profile
- d : Major diameter of external thread
- d1 : Minor diameter of external thread
- d2 : Pitch diameter of external thread
- d3 : Minor diameter of external thread on design profile
- R1 : Radius at the top of thread
- R2 : Radius at the bottom of thread
Metric Trapezoidal Thread Tolerance
- T : Tolerance
- TD1, TD2 : Tolerance for D1, D2
- Td1, Td2 : Tolerance for d1, d2
- ES : Upper deviation of internal thread
- es : Upper deviation of external thread
- EI : Lower deviation of internal thread
- ei : Lower deviation of external thread
- H : tolerance positions for lower deviation of internal thread
- c, e : tolerance positions for upper deviation of external thread
(a) Example of internal thread Tr Profile : Tr40 x 7 – 7H
- Tr : Trapezoidal thread symbol
- 40 : Size
- 7 : Pitch
- 7H : Pitch diameter tolerance symbol. “7” : tolerance grade and “H” : tolerance position
(b) Example of external thread Tr Profile : Tr40 x 7 – 7e
- Tr : Trapezoidal thread symbol
- 40 : Size
- 7 : Pitch
- 7e : Pitch diameter tolerance symbol. “7” : tolerance grade and “e” : tolerance position
There is no need to designate the other diameter tolerances since
- Their tolerance position is always the same
- Only one tolerance grade is established for the minor diameter of internal threads (D1) and for the major diameter of external threads (d)
- The tolerance grade for the minor diameter of external threads (d3) is always the same with the pitch diameter (d2)
Metric Trapezoidal Thread Dimension
Advertisement
Height of fundamental triangle :
H =
0.000
mm
Height of thread on basic profile :
H0 =
0.000
mm
Height of external thread on design profile :
h3 = H4 =
0.000
mm
Clearance between minor diameters on design profile :
ac =
0.000
mm
Radius at the top of thread :
R1 max =
0.000
mm
Radius at the bottom of thread :
R2 max =
0.000
mm
Major diameter (mm)
0.000
0.000
0.000
=
invalid size
Minor diameter (mm)
0.000
0.000
0.000
=
invalid size
Pitch diameter (mm)
0.000
0.000
0.000
=
invalid size
For not specified tolerance, we use the pitch tolerance to calculate the average value.
Metric Trapezoidal Thread Standard Series
| Size | Pitch | Ex.class | In.class |
|---|---|---|---|
| Tr 8 | 1.5 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 9 | 2 1.5 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 10 | 2 1.5 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 11 | 3 2 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 12 | 3 2 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 14 | 3 2 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 16 | 4 2 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 18 | 4 2 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 20 | 4 2 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 22 | 8 5 3 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 24 | 8 5 3 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 26 | 8 5 3 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 28 | 8 5 3 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 30 | 10 6 3 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 32 | 10 6 3 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 34 | 10 6 3 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 36 | 10 6 3 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 38 | 10 7 3 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 40 | 10 7 3 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 42 | 10 7 3 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 44 | 12 7 3 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 46 | 12 8 3 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 48 | 12 8 3 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 50 | 12 8 3 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 52 | 12 8 3 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 55 | 14 9 3 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 65 | 16 10 4 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 70 | 16 10 4 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 75 | 16 10 4 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 80 | 16 10 4 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 85 | 18 12 4 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 90 | 18 12 4 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 95 | 18 12 4 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 100 | 20 12 4 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 105 | 20 12 4 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 110 | 20 12 4 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 115 | 22 14 6 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 120 | 22 14 6 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 125 | 22 14 6 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 130 | 22 14 6 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 135 | 24 14 6 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 140 | 24 14 6 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 145 | 24 14 6 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 150 | 24 16 6 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 155 | 24 16 6 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 160 | 28 16 6 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 165 | 28 16 6 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 170 | 28 16 6 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 175 | 28 16 8 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 180 | 28 18 8 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 185 | 32 18 8 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 190 | 32 18 8 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 195 | 32 18 8 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 200 | 32 18 8 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 210 | 36 20 8 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 220 | 36 20 8 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 230 | 36 20 8 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 240 | 36 22 8 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 250 | 40 22 12 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 260 | 40 22 12 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 270 | 40 24 12 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 280 | 40 24 12 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 290 | 44 24 12 | 7e 8c 8e 9c | 7H 8H 9H |
| Tr 300 | 44 24 12 | 7e 8c 8e 9c | 7H 8H 9H |
Related topic
How to create a parallel thread profile with CAD software
How to create a 3D model of parallel thread in 3D CAD software