
890 Series Overview
The world's First all-composite butterfly valve in sizes 14" and larger
PureFlex Series 890 Butterfly Valve bodies are manufactured from Derakane 411 vinyl ester reinforced with ECR glass fiber in a proprietary process developed by PureFlex providing outstanding corrosion resistance to thousands of medias. The Lug and Full-Face 890 valves offer full flange support in FRP and light gauge metal piping systems.
The heavy cross section of the Series 890 Full-Faced and Lug PureFlexs valve also provide complete support for FRP pipe flanges which eliminates the problem of piping flange breakage at installation. The Lug style valves are directly threaded and possess steel-like thread strength to resist high torque loading. PureFlex Series 890 Butterfly Valves are available in sizes 14"-42"
Valve Body
-
Shaft
17-4PH Stainless-Double "D". All wetted areas are fully encapsulated with glass reinforced Derakane 411 resin. Other materials available. -
Corrosion Resistant
Virtually indestructible glass fiber reinforced Derakane 411 resin structure with double synthetic veil/ECR Derakane 411 corrosion liner. Valve Body rated to 150 psig, tested per MSS SP-68. Shell safety factor over 20x maximum rated working pressure. -
Seat
Double offset Viton seat retainer. Can be replaced in (60) seconds
PureFlex 890 series valve is designed for extended service life in hostile, demanding applications where expensive heavy alloy and lined valves fail.
Parts List & Materials
890 Series Valve Parts List | ||
---|---|---|
Item | Description | Material |
1 | Top Gland Bolts | 304 Stainless Steel |
2 | Top Gland | 316 Stainless Steel |
3 | Shaft Retainer Ring | 316 Stainless Steel |
4 | Shaft | 17-4PH SS/Derakane 470 |
5 | Top Packing | Virgin PTFE V-Rings |
6 | Valve Body | Fiberglass reinforced Vinyl Ester |
7 | Disc Spacer | Glass-reinforced PTFE |
8 | Disc | Fiberglass reinforced Vinyl Ester |
9 | Bottom Packing | Virgin PTFE V-Rings |
10 | Bottom Gland | 316 Stainless Steel |
11 | Bottom Gland Bolts | 304 Stainless Steel |
12 | Nuts, Bottom Shield | 304 Stainless Steel |
13 | Lock Washers | 304 Stainless Steel |
14 | Hex Head Cap Screws |
304 Stainless Steel |
15 | Bottom Shield | Epoxy-coated Carbon Steel |
16 | Seat Ring | Viton/Aluminum back-up ring |
Technical Data
Series 890 Butterfly Valves Dimensions & Weights

Flange Bolting Requirements
The following chart shows the number and size of bolts required for installation. (Flange-to-flange through-bolting)
CF = Consult Factory | |||
Size (in.) | Size (mm) | No. Bolts | Diameter |
14" | 350 | 12 | 1.00 |
16" | 400 | 16 | 1.00 |
18" | 450 | 16 | 1.12 |
20" | 500 | 20 | 1.12 |
24" | 600 | 20 | 1.25 |
26" | 650 | 24 | 1.25 |
30" | 750 | 28 | 1.25 |
36" | 900 | 32 | 1.50 |
42" | CF | 36 | 1.50 |
Flange Bolt Torques (ft-lbs. / NM)
- Minimum 15 / 20
- Maximum on dry bolt threads 50 / 68
- Maximum lubricated bolt threads35 / 47
Maximum Shutoff Pressure vs. Temperature
