Glossary

Definitions of engineering terms — what each one means, and the way it is most often misused.

110 pages in this section.

• ACME thread — Definition
• Allowance vs tolerance — Definition
• Amorphous vs semi-crystalline — Definition
• Ampacity — Definition
• Annealing vs normalising — Definition
• Anodising — Definition
• As-welded — Definition
• Austenitic stainless — Definition
• Basic dimension — Definition
• Basic dynamic load rating (C) — Definition
• Built-up edge (BUE) — Definition
• Buttress thread — Definition
• Case hardening — Definition
• Chatter — Definition
• Chip breaker — Definition
• Clearance angle — Definition
• Clearance fit — Definition
• Climb vs conventional milling — Definition
• Cold working — Definition
• Conduit fill — Definition
• Creep — Definition
• Datum — Definition
• Deflection limit (L/360 etc.) — Definition
• Depth of cut (ap) — Definition
• Derating — Definition
• Design for manufacturability (DFM) — Definition
• Duplex stainless — Definition
• EDM (electrical discharge machining) — Definition
• Effective length (K factor) — Definition
• Elongation — Definition
• Fatigue limit (endurance limit) — Definition
• Feed per tooth (chip load) — Definition
• First article inspection (FAI) — Definition
• Fits and clearances in bearings — Definition
• Flank wear — Definition
• Free-machining — Definition
• Fundamental deviation — Definition
• Galling — Definition
• Galvanic corrosion — Definition
• Gauge number — Definition
• Gauge R&R — Definition
• GD&T — Definition
• Glass transition temperature (Tg) — Definition
• Gray iron vs ductile iron — Definition
• Gummy (material) — Definition
• Hard turning — Definition
• Hardenability — Definition
• HB / HRC / HV hardness scales — Definition
• Heat-affected zone (HAZ) — Definition
• Interference fit — Definition
• IT grade — Definition
• Keyway vs spline — Definition
• ksi / ksc — Definition
• L10 life — Definition
• Machinability rating — Definition
• Material group (P/M/K/N/S/H) — Definition
• Minor diameter — Definition
• MMC / LMC (maximum and least material condition) — Definition
• Modulus vs strength — Definition
• Minimum quantity lubrication (MQL) — Definition
• Nominal size — Definition
• NPT / NPS — Definition
• Passivation — Definition
• Peck drilling — Definition
• Pitch diameter — Definition
• Poisson's ratio — Definition
• Power factor — Definition
• Precipitation hardening — Definition
• Prevailing torque — Definition
• Proof load — Definition
• Property class (8.8, 10.9, 12.9) — Definition
• Quenching and tempering — Definition
• Ra (arithmetic mean roughness) — Definition
• Radial engagement (ae) — Definition
• Radius of gyration — Definition
• Rake angle — Definition
• Relief angle — Definition
• Runout — Definition
• Rz (maximum height of profile) — Definition
• Factor of safety — Definition
• Surface speed (SFM / m/min) — Definition
• Shear center — Definition
• Slotting (full-width cut) — Definition
• Spiral point vs spiral flute tap — Definition
• Spring index — Definition
• Stress concentration — Definition
• Stress-corrosion cracking — Definition
• N grade (ISO roughness grade) — Definition
• Speed vs feed — Definition
• Tap drill — Definition
• Tensile strength (UTS) — Definition
• Thou (mil) — Definition
• Thread class (2A / 2B / 3A / 3B) — Definition
• Thread engagement — Definition
• Thread pitch — Definition
• Thread relief (undercut) — Definition
• Thread rolling — Definition
• Tolerance stack-up — Definition
• Tool life — Definition
• Tool steel letter grades (A, D, H, M, O, S, W) — Definition
• Torque vs tension — Definition
• Trochoidal milling — Definition
• True position — Definition
• UL 94 flammability rating — Definition
• UNC / UNF — Definition
• Virtual condition — Definition
• Voltage drop — Definition
• Water absorption (plastics) — Definition
• Weld symbol — Definition
• Work hardening — Definition