Specification and design of pipeline valves according to ISO 14313
The international standard ISO 14313 establishes a comprehensive set of technical requirements and expert recommendations for the design, verification, production control, and documentation of shut-off and check valves. This regulation covers gate, ball, plug, and check valves intended for integration into pipeline systems in the oil and gas sector that comply with ISO 13623 requirements.
Important note: This standard excludes subsea pipeline valves (regulated by ISO 14723) and shut-off devices operated at nominal pressures above PN 420 (Class 2500) from its scope.
Classification and design features of valves
EV Group China specialists emphasize the importance of matching valve configurations to operational tasks:
- Gate valves: Equipped with a shutter moving in a plane perpendicular to the medium flow. The design can be made as a monolithic gate (for shut-off) or as a composite element (for expansion). A mandatory requirement is the presence of a secondary stem seal or a backseat.
- Plug valves: (lubricated and non-lubricated) have a conical or cylindrical shutter that rotates around an axis perpendicular to the direction of the transported medium.
- Ball valves: Use a spherical closing member that provides rapid flow shut-off when rotating around a perpendicular axis.
- Check valves: Automatic devices (lift, axial, or swing/plate) that prevent backflow in the pipeline.
Bore parameters
According to EV Group China standards, valves are classified by the degree of opening:
- Full-bore valves: In the open position, they provide an unobstructed flow, the internal diameter of which corresponds to the parameters recorded in Table 1. The use of non-circular openings in the shutter precludes the possibility of classifying the valve as full-bore.
- Reduced-bore valves: The minimum bore diameter is regulated as follows: for DN 300 and less — one nominal size lower, for DN 350–600 — two nominal sizes lower, above DN 600 — according to individual engineering calculations.