MSS SP-99 does not cover general-purpose process valves, high-pressure hydraulic fluid power valves, or specialized control valves governed by other standards like ASME B16.34 or API 6D. Key Requirements in MSS SP-99
The most recent update, , was published in April 2023. It replaces previous editions like the 2016a and 2010 versions, ensuring that performance standards keep pace with modern industrial requirements. Scope and Application of MSS SP-99
: Includes ratings up to 15,000 psi (103.4 MPa) at 100∘F100 raised to the composed with power F ( 38∘C38 raised to the composed with power C ).
SP-99 is specifically for the small valves you see attached to pressure gauges, transmitters, and hydraulic panels.
The Definitive Guide to MSS SP-99: Standards for Instrument Valves mss sp99 pdf
The first edition of SP-99 was originally approved in July 1987 and published in October of the same year. It has since been revised, with major updates including the 1994, 2010, 2016, and 2023 editions. This table summarizes the evolution:
, these are often user-uploaded previews or potentially unauthorized copies. 🛠️ Key Technical Specifications Applies to steel and alloy valves NPS 2 and smaller. Pressure Ratings:
Covers standard dimensions for female NPT (National Pipe Thread), male NPT, tube fitting ends, and socket weld configurations. 3. Materials of Construction
: The standard applies to:
MSS SP-99 outlines design benchmarks to prevent catastrophic failures, such as stem blowout. Key design elements regulated include:
It provides the exact dimensions, wall thicknesses, and pressure ratings required to model safe piping and instrumentation diagrams (P&IDs).
Instrument valves meeting are crucial in many industries, particularly where accurate measurement and control are required. Common applications include:
: Defines mandatory pressure tests, including shell (hydrostatic) and seat leakage tests, to verify performance before installation. Why It Matters MSS SP-99 does not cover general-purpose process valves,
Hydrostatic shell test until rupture occurs. The CWP rating must be established based on the lowest recorded burst pressure of three tested specimens. Acceptance
Specifications for packing materials (like PTFE or Graphite) to minimize fugitive emissions. 4. Testing and Inspection
Rigorous vetting process ensures technical accuracy.