ISO 3019-2:2001

Overview

ISO 3019-2:2001 is the International Standard for hydraulic fluid power that establishes a metric series of mounting flanges and shaft ends for positive-displacement rotary pumps and motors. It defines standard sizes, dimensional tolerances, and an identification code so manufacturers and users can achieve dimensional interchangeability and consistent mounting interfaces across products.

Key topics and technical requirements

• Scope and types covered
  • Metric series for two- and four-bolt, and polygonal (including circular) mounting flanges.
  • Shaft end types: cylindrical keyed, conical keyed with external thread, and metric involute spline.
• Dimensions and selection
  • Standardized spigot diameters (A) and nominal shaft diameters (D) with first/second/non-preferred choices to cover likely requirements.
  • Tables and figures (Tables 1–9, Figures 1–6) specify flange/shaft dimensions and compatible spline modules/teeth.
• Tolerances and geometric requirements
  • Dimensional tolerances follow ISO 286-2; form and positional tolerances follow ISO 1101.
  • Concentricity and perpendicularity limits for flange/shaft interfaces are specified; tighter control recommended for rigid couplings.
• Keys and splines
  • Only parallel or Woodruff keys per ISO 3912 are allowed.
  • Metric involute spline parameters reference DIN/ISO conventions (see Table 3 and Figure 6).
• Identification code and designation
  • Standard code rules for flanges and shaft ends (examples from the standard):
    • Flange: Flange ISO 3019-2 - 100B4HW
    • Shaft end: Shaft end ISO 3019-2 - F32N
    • Combined: Flange and shaft end ISO 3019-2 - 100B4HW - F32N
• Sealing guidance
  • Annex A (informative) provides examples of sealing methods between flange and housing.

Practical applications and users

• Who uses it
  • Hydraulic pump and motor manufacturers, OEMs, machine designers, maintenance engineers, procurement/specification teams.
• Why it matters
  • Ensures mechanical interchangeability for mounting flanges and shaft ends across suppliers.
  • Simplifies design, reduces custom adapter needs, and improves spare-parts compatibility.
  • Supports reliable sealing arrangements and defined geometric tolerances to prevent undue loads and misalignment.
• Typical use cases
  • Specifying pump/motor interfaces in mobile and industrial hydraulic systems.
  • Cataloguing and ordering replacement units using standardized identification codes.
  • Designing mating housings, couplings and shaft couplers to ISO-compatible components.

Related standards

• ISO 3019-1 (inch series shown in metric units)
• ISO 261 (metric screw threads)
• ISO 286-2 (limits and fits)
• ISO 1101 (geometrical tolerancing)
• ISO 3912 (Woodruff keys and keyways)
• ISO 5598 (fluid power vocabulary)

Keywords: ISO 3019-2, hydraulic fluid power, mounting flanges, shaft ends, metric series, identification code, displacement pumps, hydraulic motors, flange dimensions, spline, keyed shaft.