Resources
Engineering Reference Layer
Valve Trim Selection Guide
Trim — the seats, disc, stem, wedge and ball that contact the flowing fluid — is selected separately from the body and usually decides whether a valve seals and survives. This maps 43 valve materials to the trim roles they serve.
What is valve trim and how do you select it?
Valve trim is the set of internal parts that contact and control the fluid — seats and seat rings, disc or wedge, stem, and (for ball valves) the ball. Trim is specified independently of the body: a carbon-steel body commonly carries 13Cr or SS 316 trim, and high-cycle or high-temperature seats are hard-faced with Stellite. Selection follows three rules — match corrosion resistance to the fluid, match hardness/erosion resistance to the service (hard-face for steam, throttling and repeated cycling), and match the stem to the torque and temperature. The reference below groups materials by the trim role they serve and lists each grade's trim applications.
Trim Materials by Component
Seats & Seat Rings
Stems
Discs & Wedges
Balls
Trim Applications by Grade (43 materials)
- -Gate valve wedge and seats
- -Globe valve seats and discs
- -WCB trim not recommended without hardening - typically overlaid with 13Cr or Stellite
- -Gate valve stem material
- -Globe valve stems
- -Ball valve stem - not common (usually SS 316 stem)
- -LCC trim not recommended - trim is typically SS316 or 13Cr with Stellite overlay
- -Stem material in low-temperature service; trim typically SS316
- -Stems and bonnets in Class 600–900 gate and globe valves
- -Gate valve trim for low-temperature natural gas service
- -Ball valve body end caps and bonnets in LPG service
- -WC9 valve bodies with Stellite 6 or 21 overlay on seats
- -13Cr trim for gate valve wedges
- -Hard-faced seats mandatory for repeated thermal cycling
- -F91 stems in high-temp applications
- -Stellite-overlaid seats and seating faces
- -Seat rings: 13Cr (410SS) with Stellite hard-facing (Trim 12)
- -Stem: 13Cr or 17-4PH stainless steel
- -Stems and discs in high-temperature, high-pressure service
- -Bonnet studs and nuts in Class 600–1500 valves
- -Stems and bonnets in alloy steel gate and globe valves
- -Bonnet bolting and packing followers in high-temperature service
- -Stem material in high-temperature refinery gate and globe valves
- -Disc material for globe valves in sulphur-bearing hydrocarbon service
- -Gate valve wedge with Stellite 6 overlay for high-temperature erosion resistance
- -Globe valve disc and seat overlaid with Stellite 21 for high-temperature service
- -Gate valve wedge overlaid with 13Cr for high-temperature wear resistance
- -Globe valve seat and disc with Stellite 6 overlay for erosion service
- -SS 316 trim for ball valves (stem, ball)
- -CF8M gate valve wedge and stems
- -Globe valve disc and seats - often hard-faced
- -Ball valve balls and stems
- -Globe valve stems and discs
- -Gate valve stems
- -All-CF3M construction for high-purity and pharmaceutical service
- -PTFE seats in food/pharma ball valves
- -Ball valve balls - polished SS316L (Ra ≤ 0.8 μm for pharmaceutical)
- -Gate valve seats and wedge faces
- -Globe valve stems and discs for chemical service
- -Seats and discs in sulphuric acid service globe and gate valves
- -Stems and glands in acid dosing and transfer systems
- -Stems and packing followers in food-grade and pharmaceutical valves
- -Ball and seat ring in small-bore 304L chemical ball valves
- -Seat rings and discs for extreme-temperature globe and gate valves
- -Stem material for very high-temperature valve applications
- -Gate valve stems and back-seat bushings
- -Globe valve stems and backseat rings
- -Ball and butterfly valve shafts and packing glands
- -Trim sets (seats, stems, discs) for CF8 valve assemblies
- -Back-seat bushings and bonnet flanges
- -Stems, back-seat bushings, and body-bonnet studs in high-temperature stainless valves
- -Cage and seat ring trim for globe control valves in high-temperature service
- -Duplex valve trim for seawater service
- -Hard-facing (Stellite) on seating faces recommended for gate/globe
- -Ball valve stems in seawater service
- -Duplex trim for corrosive service
- -Ball valve balls - solid Super Duplex or hard Stellite overlay on 2507
- -Seats - solid 2507 or with PTFE insert
- -Stem - Super Duplex bar per ASTM A276
- -Valve stems for seawater and offshore service (higher yield strength than 316SS stems)
- -Ball material for seawater service ball valves
- -Seat carriers and seat rings for offshore chemical injection valves
- -Seat rings and trim for offshore seawater and subsea ball valves
- -Stems and packing glands for high-chloride offshore service
- -Ball and seat inserts in seawater service (work-hardened F53 or Stellite 6 overlay)
- -Gate valve wedge overlaid with F53 weld deposit for chloride erosion-corrosion
- -Stem material for ball and gate valves in offshore chemical injection
- -Alloy 625 / Hastelloy trim for corrosive service
- -Ball valve balls and stems in Alloy 625
- -Ball valve balls and seats - overlaid or solid Inconel 625
- -Globe valve stem and disc - Alloy 625 bar stock
- -Gate valve wedge hard-facing - Inconel 625 weld overlay
- -Ball valve balls - solid Monel 400 or Monel overlay
- -Gate and globe valve seats - Monel 400 bar
- -Stem - Monel K500 (age-hardened variant) for higher strength
- -Ball valve balls and seats - solid Alloy 20 or Alloy 20 overlay
- -Globe valve disc and seat - Alloy 20 bar stock
- -Ball valve balls and seats for acid service
- -Globe valve stems and discs for chemical plant
- -Ball valve balls for highly corrosive chemical service
- -Globe valve seat and disc for mixed acid service
- -Valve positioner and instrument body parts in aggressive environments
- -Seats and balls in chemical service ball valves
- -Stems and packing followers in acid-service globe valves
- -Cage and plug trim for control valves in chlorinated environments
- -Seat rings and plug trim for corrosion-resistant valve trim in HF service
- -Stems and packing glands in Monel ball and gate valves
B265 Gr 2 / ASTM B337 / UNS R50400 (Titanium Grade 2)Titanium Grade 2 (Commercially Pure)Non-Ferrous
- -Ball valve balls and seats - solid titanium or titanium substrate with hard coating
- -Needle valve bodies for instrumentation in seawater sampling systems
- -PTFE seats and seals throughout (no separate trim specification needed - lining is the wetted surface)
- -Not typically used for trim - seats are rubber/EPDM/NBR moulded into the body
- -Ball and stem in small brass/bronze ball valves
- -Disc and seat ring in small bronze globe and gate valves
- -Seat rings (welded-in or pressed-in) hard-faced with Stellite 6 in API 600 gate valves
- -Disc hard-face overlay in high-temperature globe and gate valves
- -Plug hard-face in eccentric plug valves in erosive slurry service
- -Ball sealing surfaces in metal-seated ball valves for high-temperature service
- -Control valve cage and plug faces in erosive / flashing service
Reviewed by Materials Engineering, Vajra Industrial SolutionsDiscipline: Valve Metallurgy & Materials SelectionLast reviewed: 20 June 2026
Connected Engineering
Need a specific trim for your valves?
Tell us the service — we specify the right seat, stem and hard-facing (13Cr, SS 316, Stellite, duplex, Alloy 625) and supply with full material certification.
Products