ANSI ASA S2.75-2017 part 2 PDF

Full title and description

American National Standard Shaft Alignment Methodology, Part 2: Vocabulary — ANSI/ASA S2.75-2017/Part 2 (Reaffirmed R2020). This part defines the terminology and vocabulary used in the S2.75 series for measurement, analysis and correction of shaft alignment on rotating machinery, presenting words and phrases in alphabetical order for consistent use by practitioners and document authors.

Abstract

This standard provides a concise, authoritative vocabulary of terms unique to shaft alignment practice. It is intended to support consistent communication among engineers, alignment technicians, equipment vendors and specifiers by defining instruments, measurement methods, machine-mounting conditions, corrective-move terminology and related concepts used throughout the S2.75 methodology series.

General information

• Status: Current — published as ANSI/ASA S2.75-2017/Part 2 and reaffirmed as R2020.
• Publication date: Original publication June 6, 2017; reaffirmation (R2020) published June 19, 2020.
• Publisher: Acoustical Society of America (ASA).
• ICS / categories: Vocabularies and mechanical components — listed examples include ICS 01.040 (Vocabularies) and 21.120 (Shafts and couplings).
• Edition / version: ANSI/ASA S2.75-2017/Part 2 (R2020) — 2017 edition with 2020 reaffirmation.
• Number of pages: 26 pages.

Scope

Defines terminology unique to shaft alignment of industrial rotating machinery. The vocabulary is intended for use with the broader S2.75 Shaft Alignment Methodology series and covers terms for measurement instruments (manual and laser), alignment conditions, corrective moves and ancillary concepts referenced in Parts 1 and 3 of the series. It does not itself provide procedures or tolerances but supports clear interpretation of those materials.

Key topics and requirements

• Authoritative definitions of alignment-related terms (e.g., soft foot, coupling gap, span, offset, runout, axial/parallel misalignment).
• Vocabulary covering measurement instruments and methods including manual dial/indicator and laser detector systems.
• Terms supporting alignment quality grading and acceptance criteria described in other parts of the S2.75 series.
• Definitions used in annexes and informative material such as machine-move terminology, repeatability, OLTR (off-line-to-running) methods and pipe-strain identification.
• Consistent wording to aid specifications, training, procurement and instrumentation documentation.

Typical use and users

Used by alignment technicians, maintenance and reliability engineers, rotating-equipment designers, instrument manufacturers, consultants, training organizations and procurement/specification authors who require a common vocabulary for shaft alignment work and documentation. It is primarily a reference document to ensure consistent terminology across procedures, reports and training materials.

Related standards

This part is one component of the ASA/ANSI S2.75 Shaft Alignment Methodology series (see Part 1 — General Principles, Methods, Practices and Tolerances — and Part 3 — Alignment of vertically oriented rotating machinery). The series is maintained by ASA working group S2/WG15 and is published through the Acoustical Society of America in partnership with ANSI.

Keywords

shaft alignment; vocabulary; terminology; alignment methodology; soft foot; coupling gap; runout; offset; span; jacking screw; alignment quality grade; laser alignment; measurement repeatability.

FAQ

Q: What is this standard?

A: ANSI/ASA S2.75-2017/Part 2 (R2020) is the vocabulary component of the Shaft Alignment Methodology series; it provides definitions of terms used in shaft alignment practice and in the other parts of the S2.75 series.

Q: What does it cover?

A: It covers definitions for instruments, alignment conditions, corrective-move terminology and related concepts used in shaft alignment. It does not prescribe procedures or tolerances (those are in Part 1 and other parts), but supplies the standardized wording used by those documents.

Q: Who typically uses it?

A: Alignment technicians, maintenance/reliability engineers, equipment vendors, consultants, training providers and specification writers who need a common, authoritative vocabulary for alignment work and documentation.

Q: Is it current or superseded?

A: The document was published in 2017 and was reaffirmed/revised as R2020 (ANSI/ASA S2.75-2017/Part 2 (R2020)). It is listed as the current vocabulary part of the S2.75 series.

Q: Is it part of a series?

A: Yes — it is Part 2 of the ASA/ANSI S2.75 Shaft Alignment Methodology series; Part 1 addresses general principles, methods and tolerances, and Part 3 addresses vertically oriented machines. The series is maintained by ASA working group S2/WG15.

Q: What are the key keywords?

A: shaft alignment, vocabulary, terminology, coupling gap, soft foot, jacking screw, runout, offset, span, alignment quality grade, laser alignment.