SR685 Natural Rubber Lining
This natural gum rubber lining material provides maximum resistance to many chemicals. It is FDA compliant.
Lining Specifications
Lining Code: SR685
Type: Natural (Black)
Tie Gum: Without Tie Gum
Properties: Durometer 90 +/- 5 Shore A – Natural, semi-hard, black. A flexible ebonite lining offering maximum resistance to many chemicals. Without Tie Gum. FDA Compliant.
Cure: Exhaust Steam or Pressure Cure
Primers and Adhesive System:
- One coat Chemlok® 289 on Metal
- One coat Chemlok® 290 on Metal
- One coat Chemlok® 286 on Metal
- One coat Chemlok® 286 on Lining
Cure Time and Temperature
Cure for thickness up to ¼”
| Pressure, Saturated Steam (Autoclave) | Slowly rise to (15psi) 250°F (121°C) Hold 2 hrs. @ (15psi) 250°F (121°C) |
| Internal Steam Cure | Slowly rise to (15psi) 250°F (121°C) Hold 5 hrs. @ (15psi) 250°F (121°C) |
| Atmosphere Steam Cure | 24 hrs @ 212°F (100°C) |
Note: All reference to cure psi represents gauge pressure.
**Cure times may require tuning to compensate for low temperatures, heavy metal thicknesses, and other anomalies. Contact SRR Technical Department for recommendation on thickness over ¼”.
Storage
Ideal storage temperature is 50°F not to exceed 85°F and shelf life is 180 to 45 day range respectively.
Depending on storage conditions it may be possible to use rubber linings beyond shelf life. Please contact Salem-Republic Rubber Company for technical advisement before usage.
Designed Physical Properties
| Tensile Strength PSI | ASTM D412 | 1800 min |
| % Elongation at Break | ASTM D412 | 125 min |
| Durometer | ASTM D2240 | 90 +/- 5 |
| Specific Gravity | ASTM D297 | 1.29 |
| Adhesion to Metal | ASTM D429 | 30 pli min |
Skive: Closed
Repair lining: Same or SR669 Chemical Cure
Application Suggestions
- Plying up lining thicker than 1/4″ is not recommended due to sagging during cure process.
- Warming rubber to approximately 120°F will aide in applying and is recommended.
- SR685 is a hard rubber compound, over-cure may cause brittleness.
- Experienced applicators may have techniques which produce equal or superior results and by no means are SRR’s application suggestions meant to replace these proven techniques.
Standard Dimensions
| Roll | Standard Gauge | Tolerance | Roll Gauge | Standard Roll | Maximum |
|---|---|---|---|---|---|
| A Roll | .120 | +/-.05 | A Roll | 90ft | 96 |
| B Roll | .180 | +/-.010 | B Roll | 60ft | 66 |
| C Roll | .240 | +.010 or -.020 | C Roll | 45ft | 51 |
| 3/8” Roll | .360 | +/-.015 | 3/8” Roll | 30ft | 33 |
| ½“ Roll | .480 | +/-.015 | ½“ Roll | 23ft | 27 |
*Customer specific gauges and widths, other than standard, are available upon request. Please call Salem-Republic Rubber Company at 1-877-425-5079 with any questions or more information about our Custom Elastomeric Linings.