Low and Intermediate Alloy Steel Ball Valves – Materials and Services

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 ball valves described in
PIP PNSMV016. The valves are of low and intermediate alloy steel, with bolted or unibody, flanged (raised
faced) or socket welded, full or regular bore, and are of floating or trunnion mounted construction. Nominal
pipe sizes NPS 1
/2 to 24 for Classes 150 to 600 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 ball 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)
P18-G01 Design Limitations and Applications of Valves
P19-S01 Carbon Steel Ball Valves – Materials and Services
P19-S03 Stainless Steel Ball Valves – Materials and Services
P19-X01 Ball Valve Data Sheet
American Society for Testing and Materials (ASTM)
A 193 Alloy-Steel and Stainless Steel Bolting Materials for High Temperature Service
American Society of Mechanical Engineers (ASME)
Boiler and Pressure Vessel Code – Section I
National Association of Corrosion Engineers (NACE)
MR0175 Standard Material Requirements – Sulfide Stress Cracking
Process Industry Practices (PIP)
PNSMV006 Carbon Steel – Ball Valve Descriptions
PNSMV016 Low and Intermediate Alloy Steel – Ball Valve Descriptions
PNSMV026 Stainless Steel – Ball Valve Descriptions
PNSMV036 Bronze and Iron – Ball Valve Descriptions
3. General
3.1 The low and intermediate alloy steel ball valves described in PIP PNSMV016 and this specification
shall be used in general process services, which shall include but not be limited to general hydrocarbons,
super heated steam (ASME Section I), high pressure condensate, boiler feed water, reformed gas,
process gas, natural gas, synthesis gas, hydrogen rich hydrocarbons, hydrogen, ammonia, and caustic
wash. These low and intermediate alloy steel ball valves contain 1 to 9 chromium plus various amounts of
molybdenum.
3.2 The other specifications in this series are:
a. SES P19-S01, which covers carbon steel ball valves described in PIP PNSMV006, and used in
general process services
b. SES P19-S03, which covers stainless steel ball valves described in PIP PNSMV026, and used
in corrosive services
c. Ball valves described in PIP PNSMV036, and used in utility services
3.3 Valves in new piping systems shall conform to PIP PNSMV016 and this specification. Valves for
maintaining or tie-in to existing systems may be in accordance with original specifications.

3.4 PIP PNSMV016 describes the valves, their components, and their materials of construction. The trim
for ball valves comprises the ball, stem, and the metal seat or seat retainers and small internal parts that
contact the service fluid.
3.5 The valves have unique valve number designations, for example BA-140, by which they are referred to
in the PIP line classes. See PIP PNSMV016 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 P19-X01. This shall be attached to the requisition/purchase order.
4. Additional Material Requirements
For services where the materials specified in PIP PNSMV016 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 and bonnet. 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 Chrome molybdenum materials, 2 1
/4 Cr-1Mo in particular, tend to degrade when subjected to
repeated weldings and subsequent stress reliefs. This shall be mitigated either by metallurgical control or
by step cooling. A third alternative shall be to limit the number of heat treatments, to limit the total
tempering.
4.5 Cyanides, acids, acid salts 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.
4.6 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.
4.7 The identification plate material shall be austenitic stainless steel or nickel alloy.

Leave a Comment

error: Content is Protected.