Diaphragm seal with threaded connection
Description
Diaphragm seals are used for the protection of pressure measuring instruments in applications with difficult media. In diaphragm seal systems, the diaphragm of the diaphragm seal effects the separation of the instrument and the medium. The pressure is transmitted to the measuring instrument via the system fill fluid which is inside the diaphragm seal system.
For the implementation of demanding customer applications, there is a wide variety of designs, materials and system fill fluids available.
For further technical information on diaphragm seals and diaphragm seal systems see IN 00.06 'Application, operating principle, designs'.
Diaphragm seal with threaded connection, model 990.31
The model 990.31 diaphragm seal with threaded connection in a plastic version is suitable for versatile application areas in the water supply and wastewater treatment industries.
Mounting of the diaphragm seal to the measuring instrument may be made via a direct connection or a flexible capillary.
The WIKA model 990.31 diaphragm seal is used successfully in chemical plant construction, electroplating and wastewater treatment applications.
Special features
- All-plastic version
| Model | 990.31 |
| Product family | 990 |
| Subcategory | Diaphragm seal |
| Pressure ranges | 0…2.5 bar · 0…10 bar · 0…36 psi · 0…145 psi |
| Process connection | G ¼ female¼ NPT femaleG ½ female½ NPT femaleG1/4G1/21/4NPT1/2NPT |
| Process temperature | −40…+140 °C |
| Case material | PP (polypropylene), glass-fibre reinforced, blue RAL 5022, PP(polypropylene), grey RAL 7032, PVDF(polyvinylidene fluoride), opaque,yellowish-white |
| Wetted parts material | PVC-U (polyvinyl chloride without plasticiser), grey RAL 7011, PP (polypropylene), grey RAL 7032, PVDF (polyvinylidene fluoride), opaque, yellowish-white, PVDF (polyvinylidene fluoride), EPDM, media side with PTFE foil |
| Sealing material | EPDM, media side with PTFE foil, EPDM |
| Ambient temperature | +10…+40 °C |
| Certifications | EACCRNMTSCHS |
| Datasheet languages | EN |
| Model 990.31 | Standard | Option |
|---|---|---|
| Pressure range | 0 ... 2,5 bar to 0 ... 10 bar [0 ... 36 psi to 0 ... 145 psi] | |
| Operating pressure and process temperature | See pressure-temperature diagrams from page 4 | |
| Origin of wetted parts | EU | - |
| Connection to the measuring instrument | ■ G¼female ■ G½female | ■ ¼NPTfemale ■ ½NPTfemale |
| Process connection | ■ G ¼ female ■ G½female | ■ ¼ NPT female ■ ½NPTfemale |
| Type of mounting | Direct mounting | Capillary |
| Instrument mounting bracket (only for capillary option) | - | ■ Form H per DIN 16281, 100 mm, aluminium, black ■ Form H per DIN 16281, 100 mm, stainless steel ■ Bracket for pipe mounting, for pipe outer Ø20 ... 80 mm, steel (see data sheet AC 09.07) |
| G | DN 1) | d |
|---|---|---|
| G ¼ | 20 [0.787] | 25 [0.984] |
| G½ | 25 [0.984] | 32 [1.260] |
| ¼ NPT | 20 [0.787] | 25 [0.984] |
| ½NPT | 25 [0.984] | 32 [1.260] |
| Upper body of diaphragm seal | Wetted parts | |
|---|---|---|
| Lower body of diaphragm seal | Diaphragm with sealing | |
| PP (polypropylene), glass-fibre reinforced, blue RAL 5022 | PVC-U (polyvinyl chloride without plasticiser), grey RAL 7011 PP (polypropylene), grey RAL 7032 PVDF (polyvinylidene fluoride), | EPDM, media side with PTFE foil |
| Logo | Description | Country |
|---|---|---|
| EAC (option) Pressure equipment directive | Eurasian Economic Community | |
| - | CRN Safety (e.g. electr. safety, overpressure, ...) | Canada |
| - | MTSCHS (option) Permission for commissioning | Kazakhstan |
View all (7)
| Material | Unified numbering system (UNS) |
|---|---|
| Stainless steel 316L (1.4404 or 1.4435) | S31603 |
| Stainless steel 904L (1.4539) | N08904 |
| Stainless steel 321 (1.4541) | S32100 |
| Stainless steel 316Ti (1.4571) | S31635 |
| Stainless steel 1.4466 (urea grade) | S31050 |
| Duplex 2205 (1.4462) | S31803 |
| Superduplex 1.4410 | S32750 |
| Tantalum (also lining) | R05200 |
| Hastelloy C276 (2.4819) | N01276 |
| Hastelloy C22 (2.4602) | N06022 |
| Inconel 600 (2.4816) | N06600 |
| Incoloy 825 (2.4858) | N08825 |
| Inconel 625 (2.485) | N06625 |
| Monel 400 (2.4360) | N04400 |
| Nickel 200 (2.4066) | N02200 |
| Nickel 201 (2.4068) | N02201 |
| Titanium 3.7035 (class 2) | R50400 |
| Titanium 3.7235 (class 7) | R52400 |
| Zirconium GR702 | R60702 |
| Designation | Identi- fication number | Solidi- fication point | Boiling/ degradation point | Density at 25 °C | Kin.Viscosity at 25 °C | Remark |
|---|---|---|---|---|---|---|
| KN | °C | °C | g/cm³ | cSt | ||
| Silicone oil | 2 | -45 | +300 | 0.96 | 54.5 | Universal application |
| Glycerine | 7 | -35 | +240 | 1.26 | 759.6 | FDA 21 CFR 182.1320 |
| Silicone oil | 17 | -90 | +200 | 0.92 | 4.4 | Low temperatures |
| Halocarbon | 21 | -60 | +175 | 1.89 | 10.6 | Oxygen 1) and chlorine |
| Methylcyclopentane | 30 | -130 | +60 | 0.74 | 0.7 | For very low temperatures |
| High-temperature silicone oil | 32 | -25 | +400 | 1.06 | 47.1 | For high temperatures |
| Neobee® M-20 | 59 | -35 | +260 | 0.92 | 10.0 | FDA 21 CFR 172.856, 21 CFR 174.5 |
| DI water | 64 | +4 | +85 | 1.00 | 0.9 | For ultrapure media |
| Silicone oil | 68 | -75 | +250 | 0.93 | 10.3 | |
| DI water/propanol mixture | 75 | -30 | +60 | 0.92 | 3.6 | For ultrapure media |
| Medicinal white mineral oil | 92 | -15 | +260 | 0.85 | 45.3 | FDA 21 CFR 172.878, 21 CFR 178.3620(a); USP, EP, SP |
| Maximum temperature | Maximum oxygen pressure |
|---|---|
| to 60 °C | 50 bar |
| > 60 °C to 100 °C | 30 bar |
| > 100 °C to 175 °C | 25 bar |
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