ISO 11687-2:2020

Overview

ISO 11687-2:2020 - "Plain bearings - Pedestal plain bearings - Part 2: Side flange bearings" specifies design characteristics for side flange bearings and associated shaft design for the size range 9 to 28. It is intended mainly for use in the electrical and turbo engineering industries and provides standardised dimensions, materials, tolerances, surface finishes, and designation rules to ensure interchangeability and reliable performance.

Key topics and technical requirements

• Scope and sizes: Applies to side flange bearings in size range 9–28 and corresponding shaft dimensions.
• Types and classification: Letter symbols define housing, cooling, bore shape/lubrication and thrust-bearing type (e.g., F = housing with cooling fins; Z = recirculating oil with external cooling; C/L/Y/V = bore types; Q/B/K/A = thrust-bearing types).
• Dimensions and tables: Dimensional requirements for housings and shafts are specified in Table 1 and Table 2 (figures provided in the standard). Conformance is required to specified dimensions rather than to illustrative designs.
• Materials:
  • Housing: grade 300 cast iron (ISO 185) or agreed alternatives.
  • Half-bearing backs: S235 B, C10R/C15R, or GE 200/GS 200 (various ISO refs).
  • Bearing metal: tin-casting alloy per ISO 4381.
  • Seals and oil rings: copper/aluminium/plastic (subject to agreement); oil ring copper‑zinc per ASTM B124/B124M.
• Surface finish & tolerances:
  • Machined tolerances: ISO 2768-1/2 (mH); unmachined per ISO 8062-3 (DCTG 9).
  • Surface roughness: mounted surfaces Ra = 3.2 µm; sliding surfaces Ra = 0.8 µm (ISO 1302).
  • Shaft limits and form/tolerances per ISO 12129-1/2.
• Housing & design details: Lifting/transport provisions, oil-space pressure compensation openings, corrosion protection, inspection plates, and connection provisions (both sides) are specified or left to agreement. Bolts for housing flange are not part of delivery.
• Designation example: Side flange bearing ISO 11687‑2 - 14 - 125 - FZLK

Practical applications and who uses it

• Used by bearing manufacturers, OEMs, mechanical designers, rotating-equipment engineers, maintenance/specification teams, and procurement professionals specifying pedestal plain bearings for generators, turbines, motors and similar rotating machinery.
• Practical benefits include interchangeability, clear specification of lubrication and cooling options, standardized shaft fits, and predictable performance and maintenance planning.

Related standards (normative references)

Key referenced standards included in ISO 11687-2:2020:

• ISO 185, ISO 630‑2, ISO 683‑3, ISO 1302, ISO 2768‑1/2, ISO 4381, ISO 8062‑3, ISO 12129‑1/2, ISO 14737, ASTM B124/B124M.

Keywords: ISO 11687-2:2020, side flange bearings, pedestal plain bearings, plain bearings, shaft design, surface roughness, bearings dimensions, lubrication, electrical engineering, turbo engineering.