OST 24.125.02-89 PDF
Name in English:
OST 24.125.02-89
Name in Russian:
ОСТ 24.125.02-89
Butt joint welds for NPP pipelines. Types and main dimensions
Full title and description
OST 24.125.02-89 — "Швы сварные стыковых соединений трубопроводов АЭС. Типы и основные размеры" (English: "Butt joint welds for NPP pipelines. Types and main dimensions"). The standard defines types, geometry and principal dimensions of butt welds used on nuclear power plant pipeline systems.
Abstract
This industry standard prescribes types and basic dimensional parameters for butt-welded joints of pipelines used in atomic (nuclear) power plants. It is intended to ensure uniformity of weld joint types, edge preparation and dimensional limits for NPP piping to meet assembly, inspection and safety requirements.
General information
- Status: Active / Industry standard (document in force as an OST document in the OST 24 series).
- Publication date: Approved 26 May 1989; introduction into effect 1 January 1990.
- Publisher: Approved and introduced by the USSR Ministry of Heavy, Power and Transport Machine-Building (Мин. тяжелого, энергетического и транспортного машиностроения СССР). Registered in the central standards fund.
- ICS / categories: Nuclear power engineering and piping/welding related categories (e.g. ICS 27 — Energy and heat transfer engineering / 27.120 — Nuclear energy engineering; related welding/piping classifications).
- Edition / version: Original OST edition, 1989 (OST 24.125.02-89). No newer national replacement noted in the document record.
- Number of pages: 9 pages (electronic/pdf available copies indicated as 9 pages).
Scope
Applies to butt-welded joints of pipelines used in nuclear power plants (NPPs). The standard covers joint types, edge (bevel) preparations, nominal dimensional series and key dimensional limits for butt welds of piping that fall under the rules for design and safe operation of NPP equipment and pipelines (referenced PNAE rules). It is intended for use where uniform weld geometry and compatibility with inspection and assembly procedures are required.
Key topics and requirements
- Classification of butt-weld types used on NPP pipelines (typical joint forms and seam types).
- Principal dimensional parameters: bevel angle, root face, gap, groove dimensions and nominal sizes for a range of pipe diameters and wall thicknesses.
- Edge preparation (разделка кромок) details and minimum/maximum dimensional tolerances for assembly and weld deposition.
- Recommended weld seam types and notes on theoretical deposited metal mass for particular joint variants.
- References to related normative documents and materials/consumables standards used for welding of NPP piping.
Typical use and users
Used by plant designers, piping engineers, welding specialists, fabrication shops, quality assurance and inspection teams, and regulatory bodies responsible for nuclear power plant construction and maintenance. Also used as a reference in procurement and manufacturing specifications for NPP piping assemblies and prefabricated pipeline blocks.
Related standards
References and related normative documents commonly cited together with OST 24.125.02-89 include PNAE rules for NPP piping (for example PNAE G-7 series), various GOST and OST normative documents on materials and welding (examples listed in OST metadata), and other OST 24.125 series standards covering fittings, supports and pipeline details used in thermal and nuclear power plant systems. OST 24.125.02-89 replaced earlier OST documents in related areas as noted in the registration data.
Keywords
OST 24.125.02-89; butt weld; butt joint; pipeline welds; NPP piping; nuclear power plant; weld geometry; bevel preparation; welding dimensions; welding standard.
FAQ
Q: What is this standard?
A: OST 24.125.02-89 is an industry (OST) standard that specifies types and main dimensions of butt-welded joints for pipelines used in nuclear power plants.
Q: What does it cover?
A: It covers the geometry and principal dimensional requirements of butt welds on NPP pipelines — including bevel preparations, nominal sizes, tolerances and recommended seam types — to ensure interchangeability, manufacturability and inspectability in nuclear plant piping systems.
Q: Who typically uses it?
A: Piping designers and engineers, welding shops and inspectors who fabricate and assemble NPP pipeline systems, procurement specialists specifying welded pipe spools or blocks, and regulators or licensors reviewing conformity to NPP piping rules.
Q: Is it current or superseded?
A: Document records list OST 24.125.02-89 as the OST 1989 edition and sources that distribute the standard indicate it as active in OST catalogues; earlier OST documents in this subject area were superseded by this 1989 edition as recorded at registration. Users should check national/regulatory updates for any more recent national technical regulations that may affect legal applicability.
Q: Is it part of a series?
A: Yes — it belongs to the OST 24.125 series of industry standards for pipelines, fittings and related components used in thermal and nuclear power plants; related OST 24.125.xx documents cover other piping components, supports and dimensions.
Q: What are the key keywords?
A: Butt weld, butt joint, weld seam, bevel, pipe joint dimensions, NPP pipelines, OST 24.125, welding for nuclear power plants.