1. SCOPE
…………………………………………………
2. REFERENCES
3. GENERAL
4. ADDITIONAL MATERIAL REQUIREMENTS
1. Scope
1.1 This specification is to assist the user in the application and adaption of the gate valves described in
PIP PNSMV023. The valves are of stainless steel, with bolted, welded or pressure-seal bonnet, flanged
(raised faced) or welding ended (butt or socket), and are of outside screw and yoke (OS&Y) construction.
Nominal pipe sizes NPS 1
/2 to 24 for Classes 150 to 1500 are covered.
1.2 This specification shall be used in conjunction with SES P18-G01.
1.3 This specification is one of a four part series for gate valves, each of which represents a group of like
materials, see 3.2.
2. References
Reference is made in this specification to the following documents. The latest issues, amendments, and
supplements to these documents shall apply unless otherwise indicated.
SABIC Engineering Standards (SES)
P02-S01 Piping Materials Standards Specification-Part 1, Group 1
P18-G01 Design Limitations and Applications of Valves
P18-S01 Carbon Steel Gate Valves – Materials and Services
P18-S02 Low and Intermediate Alloy Steel Gate Valves – Materials and Services
P18-X01 Gate Valve Data Sheet
American Society of Testing and Materials (ASTM)
A 193 Alloy-Steel and Stainless Steel Bolting Materials for High Temperature Service
National Association of Corrosion Engineers (NACE)
MR0175 Standard Material Requirements – Sulfide Stress Cracking
Process Industry Practices (PIP)
PNSMV003 Carbon Steel – Gate Valve Descriptions
PNSMV013 Low and Intermediate Alloy Steel – Gate Valve Descriptions
PNSMV023 Stainless Steel – Gate Valve Descriptions
PNSMV033 Bronze and Iron – Gate Valve Descriptions
3. General
3.1 The stainless steel gate valves described in PIP PNSMV023 and this specification shall be used in
lube oil and other corrosive services, and low temperature and cryogenic services.
3.2 The other specifications in this series are:
a. SES P18-S01, which covers carbon steel gate valves described in PIP PNSMV003, and used in
general process services
b. SES P18-S02, which covers low and intermediate alloy steel gate valves described in
PIP PNSMV013, and used in general process services
c. Gate valves described in PIP PNSMV033, and used in utility services
3.3 Valves in new piping systems shall conform to PIP PNSMV023 and this specification. Valves for
maintaining or tie-in to existing systems may be in accordance with original specifications.
3.4 PIP PNSMV023 describes the valves, their components, and their materials of construction. The trim
for gate valves comprises the stem, body and gate seating surfaces, bushing and small internal parts that
contact the service fluid.
3.5 The valves have unique valve number designations, for example GA-122, by which they are referred
to in the PIP line classes. See PIP PNSMV023 Section 6 for applicable line classes.
3.6 All design, material, service, inspection, marking, documentation, shipping and other requirements
shall be specified on the data sheet SES P18-X01. This shall be attached to the requisition/purchase order.
4. Additional Material Requirements
For services where the materials specified in PIP PNSMV023 are inadequate, the following requirements
shall be met:
4.1 Materials shall be suitable for continuous exposure at the service conditions and ratings specified.
4.2 Valve components in rubbing or sliding contact shall not gall.
4.3 The corrosion resistance of body-bonnet and packing gland bolting, and ring joint gasket material shall
be at least equal to the material of the body, bonnet and yoke. However, the bolting material is not required
to be more corrosion resistant than austenitic stainless AISI type 304 (in accordance with ASTM A 193)
unless otherwise specified in the purchase order.
4.4 Halides and wet H2S, or sour service promote sulfide (stress corrosion) cracking. This situation shall
be mitigated by maintaining maximum ductility in the valve parts. Maximum hardness limits shall be as
specified in NACE MR0175. Body-to-bonnet bolting shall be in accordance with NACE MR0175 Class III.
However, when the valve is to be insulated, or buried, it shall be in accordance with NACE MR0175 Class I
or II. Weldments shall be stress relieved in accordance with NACE sections 3 and 4.
4.5 Gate valves in cold service, below -46 °C, shall have special requirements. The body and bonnet shall
be of type 304, or 316 stainless steel, which has sufficient ductility. The trim shall also be stainless steel,
type 304 or 316. Any lubricants shall be designed for the temperature. Bonnet and gland bolting shall be
austenitic stainless steel ASTM A 320. The corresponding nuts shall be ASTM A 194 Grade 8.
4.6 Gate valves in service below -73 °C need all of the above specifications and also the following. The
valves, including trim, shall be made entirely of stainless steel, type 304 or 316. Type 304 shall not be
substituted for type 316 without SABIC approval. Type 316 has better ductility down to -198 °C. Below that
temperature, impact testing is required for either type 304, or type 316. Impact resistance of stainless steel
shall conform to the requirements of SES P02-S01.
4.7 The packing material shall be chemically compatible with the fluid, and have sufficient sealing
properties at the temperature of operation. Packing shall be asbestos-free, and corrosion inhibited, to avoid
stem pitting. In hydrocarbon services, packing and stem seals shall not be pure polymer/elastomer unless
the valves have been qualified as fire safe.