TRtrapezoidal30° flankISO 2901

Tr24 × 5 Thread Dimensions

Tr 24 × 5 is a trapezoidal Trapezoidal thread. Pitch is 5 mm, equivalent to 5.08 threads per inch. The recommended tap drill leaves roughly 75% thread engagement.

Major Ø24 mm
Pitch5 mm
Threads per inch5.08
Pitch Ø21.5 mm
Tap drill19 mm

Thread profile

millimetres unless stated
Thread profile — Tr 24 × 5d 24d2 21.5d3 21mm30°P 5h3 2.75tap ⌀19
Tr24 × 5 — basic profile30° flank angle · Not to scale

Basic information

Designation
Tr 24 × 5
Thread system
Trapezoidal
Series
trapezoidal
Standard
ISO 2901
Basic profile
Trapezoidal basic profile
Flank angle
30°

Dimensions

Major diameter
24 mm
Pitch
5 mm
Threads per inch
5.08
Pitch diameter
21.5 mm
Minor diameter (external)
21 mm
Minor diameter (internal)
19 mm
Thread depth
2.75 mm
Recommended tap drill
Ø 19 mm

How these values are derived

computed from the basic profile

These figures follow the Trapezoidal basic profile of ISO 2901. A 60° basic profile uses a fundamental triangle height H = 0.866025 × P, with external minor diameter d₃ = d − 1.226869 × P and internal minor diameter D₁ = d − 1.082532 × P; the two differ because the external root is rounded while the internal crest is truncated. A 55° Whitworth profile uses H = 0.960491 × P and a thread height of 0.640327 × P. The recommended tap drill is given as nominal diameter minus pitch, which approximates 75% thread engagement — adjust it for tough materials or deep holes.

Compatible parts0 specification pages

No specification in this database uses Tr24 × 5. Power threads are not fastener threads — they are found on lead screws, jacks and vice screws, so no bolt or nut in this catalogue is made in this form. The geometry above is what a machinist needs to cut it.

Related

Other pitches at the same 24 mm diameter — a fine pitch on a coarse diameter, or the reverse, is the usual substitution question.

Neighbouring sizes in Trapezoidal.