Stainless Steel · Fittings · ASTM A403 WP321H
SS 321H Stainless Steel Fittings
In short: SS 321H fittings, butt-weld to ASTM A403 WP321H and forged to A182 F321H, match SS 321H piping in refinery and heater service.
- S32109
- UNS number
- 7.93
- density, g/cm³
- 3.1 / 3.2
- EN 10204 certificates
- 5
- SS 321H product forms
Why this combination
Why SS 321H in fittings
Fittings in hot hydrogen lines must match the pipe's creep properties and stabilisation.
PMI every fitting: SS 321H and SS 304H fittings look identical.
Specification
How to specify SS 321H fittings
Butt-weld ½" – 48" (larger fabricated to order) in schedules matching the pipe; socket-weld and threaded ⅛" – 4" in Class 2000, 3000, 6000 and 9000
- Specification
- ASTM A403 WP321H (butt-weld); A182 F321H (forged)
- UNS
- S32109
- EN / W.Nr.
- 1.4878
- Butt-weld
- A403 WP321H
- Forged
- A182 F321H
Sizes and weights
SS 321H fittings sizes, weighed at 7.93 g/cm³
Other sizes on request. For general fittings information, such as manufacturing routes and end finishes, see the fittings guide.
Butt-weld ½" – 48" (larger fabricated to order) in schedules matching the pipe; socket-weld and threaded ⅛" – 4" in Class 2000, 3000, 6000 and 9000
Chemistry
SS 321H composition
- UNS
- S32109
- EN / W.Nr.
- 1.4878 · X8CrNiTi18-10 (related)
- Density
- 7.93 g/cm³
| Element | Limit, % | Why it matters |
|---|---|---|
| C | 0.04 – 0.10 | |
| Mn | 2.00 max | |
| P | 0.045 max | |
| S | 0.030 max | |
| Si | 0.75 max | |
| Cr | 17.0 – 19.0 | |
| Ni | 9.0 – 12.0 | |
| Ti | 4×(C+N) – 0.70 | |
| N | 0.10 max |
Limits per ASTM A240; other product forms and specifications differ slightly. Your order's specification and edition govern.
Questions
About SS 321H fittings
Are WP321H fittings available seamless?
Yes, in common sizes.
Do you PMI fittings?
On request, piece by piece.
From enquiry to dispatch
How a SS 321H fittings order runs
- 01 EnquiryGrade, specification, size, quantity
- 02 ReviewChecked against your standard
- 03 InspectPMI, dimensions, TPI if required
- 04 CertifyEN 10204 3.1 / 3.2, heat traceable
- 05 ShipPacked and documented for the destination
Need SS 321H fittings?
Send size, quantity, specification and destination. We reply with availability, certificates and delivery.