REOTEMP Fill Fluid Guide
Diaphragm seals are designed to protect pressure instruments from hot process media and corrosive chemicals while minimizing any negative effect on instrument accuracy and durability. A well-made diaphragm seal can achieve this goal only if it is properly assembled, filled, and tested. REOTEMP’s highly trained technicians use state-of-the-art equipment so that every diaphragm seal assembly is filled and tested to assure optimal instrument performance:
- 24-hour Minimum Fluid De-gassing
- Evacuated Instrument Chamber Up to 10-8 mbar Absolute
- Complete Fill Integrity Check
- Fill-port Leak Test
- Post-fill Static Test
- Verification of Instrument Calibration
- High-temp Pipe Sealant Used on All Threaded Joints (Welded Joints Upon Request)
- Tamper-proof (Inspection Seal) Lacquer used on All Threaded Joints
- Sturdy Diaphragm Packaging Protection
Standard Fill Fluid
| Part Number Code | Name | Description | Temperature Range (≥ 1 bara) | Viscosity cst at ~77ºF | Specific Gravity at ~77ºF | Thermal Expansion cc/cc/ºC |
|---|---|---|---|---|---|---|
| AS | Silicone DC200 |
This is the standard fill fluid for most diaphragm seal applications. |
-40ºF to 400ºF | 20 | 0.94 | .00104 |
High Temperature Silicone
| Part Number Code | Name | Description | Temperature Range (≥ 1 bara) | Viscosity cst at ~77ºF | Specific Gravity at ~77ºF | Thermal Expansion cc/cc/ºC |
|---|---|---|---|---|---|---|
| BH | Silicone DC704 |
Standard for Smart Transmitters and capillary systems. Performs well in applications with high temperature and a deep vacuum. |
0ºF to 650ºF | 44 | 1.07 | .00077 |
| B1 | Silicone DC710 |
Highest temperature rating; ideal for gauge seal assemblies. Too thick for capillary assemblies. Response time can become very slow in cold conditions. |
50ºF to 750ºF | 500 | 1.11 | .00043 |
| C8 | Syltherm 800 |
Low viscosity allows it to perform well in both low and high temperatures. Not recommended for vacuum service or at high temperatures when under low static pressure. |
-40ºF to 750ºF | 9.5 | 0.93 | .00136 |
| B5 | Silicone DC705 |
Performs very well in high temperatures when under vacuum. The high viscosity and freezing point of this fluid makes it a poor choice for cold or outdoor installations without heat tracing. |
50ºF to 675ºF | 175 | 1.09 | .00096 |
| B2 | Silicone DC550 |
Similar high temperature performance as DC705, however it performs better at lower temperatures. |
-40ºF to 575ºF | 125 | 1.07 | .00076 |
Food Grade
| Part Number Code | Name | Description | Temperature Range (≥ 1 bara) | Viscosity cst at ~77ºF | Specific Gravity at ~77ºF | Thermal Expansion cc/cc/ºC |
|---|---|---|---|---|---|---|
| AG | Glycerin USP |
This is the standard fill fluid for most gauge seal assemblies for food, beverage, and pharmaceutical applications. Its high viscosity will cause very slow response at times in low temperature and outdoor installations. |
60ºF to 450ºF | 1100 | 1.26 | .00061 |
| BN | NEOBEE M20 |
Low viscosity and a wide temperature range makes this the standard sanitary fill fluid for Smart Transmitters and capillary systems. |
-10ºF to 400ºF | 10 | 0.92 | .00101 |
| BS | Food Grade Silicone |
Highest temperature limit for food grade fluids. Because of its high viscosity it does not perform well in low temperatures. |
20ºF to 550ºF | 350 | 0.97 | .00096 |
| BP | Propylene Glycol |
This is the fill fluid used when Glycol is called for on the customer specification. It has a very narrow temperature range. |
0ºF to 200ºF | 2.85 | 1.03 | .00073 |
Inert (Typically for Chlorine and Oxygen Applications or in Silicone-free Environments
| Part Number Code | Name | Description | Temperature Range (≥ 1bara) | Viscosity cst at ~77ºF | Specific Gravity at ~77ºF | Thermal Expansion cc/cc/ºC |
|---|---|---|---|---|---|---|
| C1 | Fomblin Y06 |
Ideal inert fluid for transmitter applications. Relatively high vapor pressure above 200ºF. Not recommended for use in high temperature situations with low static pressure. |
-40ºFto 450ºF | 71 | 1.88 | .00086 |
| C2 | Halocarbon 6.3 |
Standard inert fluid used in gauge seal assemblies. |
-40ºF to 400ºF | 6.3 | 1.87 | .00084 |
| C3 | Halocarbon 1.8 |
Typically used in low temperature applications because of its low viscosity. |
-110ºF to 220ºF | 1.8 | 1.82 | .00084 |
| C4 | Fluorolube FS-5 |
Similar performance to Halocarbon 6.3, however not suitable for vacuum service. |
-40ºF to 450ºF | 5 | 1.86 | .00087 |
Specialty
| Part Number Code | Name | Description | Temperature Range (≥ 1 bara) | Viscosity cst at ~77ºF | Specific Gravity at ~77ºF | Thermal Expansion cc/cc/ºC |
|---|---|---|---|---|---|---|
| CK | Krytox 1506 |
Specialty fill fluid, inert. |
-40ºF to 350ºF | 62 | 1.88 | .00095 |
| BE | Ethylene Glycol |
Occasionally used in annular (O-ring) seal assemblies. |
-25ºF to 320ºF | 30 | 1.10 | .00062 |
Note: PulsePlus™ fill fluids may have different physical properties than specified. Chemical composition and temperature ranges do not vary.
Silicone DC200, Silicone DC710, Silicone DC705, Silicone DC550 are trademarks of Dow Corning.
Syltherm 900 is a trademark of The Dow Chemical Company.
Halocarbon 6.3 and Halocarbon 1.8 are trademarks of Halocarbon Product Corporation.
Fomblin Y06 is a trademark of AUSIMONT S.P.A.
Fluorolube FS-5 is a trademark of Hooker Chemical Company.
Krytox 1506 is a trademark of The Chemours Company FC, LLC.
NEOBEEM20 is a trademark of Stepan Specialty Products.