Industrial and Construction Basics Two

OD

Outside diameter.

Parallelism

The permissible variation of the parallel relationship of the top surface diameter to the bearing surface diameter of a part.

Perpendicularity

The permissible perpendicular variation of relationship between the bearing surface or the top surface and the axis of the thread (A.k.a. runout or TIR).

Pitch

The pitch of a thread having uniform spacing is the distance, measured parallel to its axis, between corresponding points on adjacent thread forms in the same axial plane and on the same side of the axis. Pitch is equal to the lead divided by the number of thread starts. (see Thread Pitch)

Pitch Diameter

In thread geometry, the diameter of an imaginary cylinder of such diameter and location of its axis that its surface would pass through a straight thread in such a manner as to make the width of the thread ridge and the width of the thread groove equal. The pitch diameter is located, therefore, midway between the sharp major and sharp minor diameters of a given thread form.

Radiused Corner

Slight radii at slot corners.

Round Bottom

Bottom of the slot is rounded.

Runout

The permissible perpendicular variation of relationship between the bearing surface or the top surface and the axis of the thread (A.k.a. TIR or perpendicularity).

Shape

The shape of the largest outside feature of the part.

Slot

The following types of slots are typical for nuts:

Bearing Surface Radial Slots

Horizontal Slots on the OD

Top Radial Slots

Vertical Slots on the OD

Slot Bottom Contour

INC is capable of producing slots with the following bottom contours: Broken Corner, Radiused Corner, Round Bottom, Angled Bottom.

Slot Span

The distance as measured from one slot bottom to the opposing slot bottom of a part with an even number of OD slots.

Slot Width

The perpendicular distance measured between the parallel sides of the slot.

Style

The description of the part as it fits in to a family classification of similar part designs or functions.

Tap Size

The nominal major diameter as given in the thread designation, of a threaded primary hole.

Thickness

The distance from the bearing surface to the top surface measured parallel to the axis of the part.

Thread Fit

A alphanumeric designation used to identify the extreme permissible limits of the pitch diameter. Standard thread fits for Industrial Nut Corp. would be '2B' for inch threads and '6H' for metric threads.

Thread Handedness

Whether the threads are right-handed or left-handed in orientation.

Threaded Length

The depth to which the part is to contain fully formed threads, not including the tapering off of the thread form for threaded partial holes. For a through threaded part this would equal the thickness of the part.

Thread Pitch

The number of threads per inch for inch threads, or the distance between threads for metric threads. (see Pitch)

Thread Series

Groups of diameter/pitch combinations distinguished from each other by the number of threads per inch applied to specific diameters.

Through-hardened

A process by which the entire cross section of the part is hardened. A minimum core hardness may be specified.

TIR

The permissible perpendicular variation of relationship between the bearing surface or the top surface and the axis of the thread (A.k.a. runout or perpendicularity).

Tolerance

The total amount of variation permitted for the size of a dimension.

Top Radial Slots

Slots that are milled perpendicular to the axis of the part into the top surface.

Unslotted Thickness

The distance as measured from the bottom of the slot to either the bearing surface (for top radial slots) or the top surface (for bearing surface radial slots) of the part.