SR655 Natural Rubber Lining
This natural gum rubber lining material provides excellent chemical, tear and abrasion resistance. It is a highly reinforced compound with Tie Gum.
Lining Specifications
Lining Code: SR655
Type: Natural
Tie Gum: With or Without Tie Gum
Properties: 60 +/- 5 Shore A – Natural, soft, black, excellent chemical, tear and abrasion resistance a highly reinforced compound with Tie Gum.
Cure: Exhaust Steam or Pressure Cure
Note: Natural rubber will “weather check” (prematurely degrade) if exposed to sunlight, ozone, and oxygen.
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) | 1 hr. @ 20psi 260°F (126°C) |
| Internal Steam Cure | 3 hrs.@ 20psi 260°F (126°C) |
| Atmosphere Steam Cure | 24 hrs. @ 190°F-205° (87°C-96°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 recommendations on lining thicknesses 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 | 3500 min |
| % Elongation at Break | ASTM D412 | 550 min |
| Durometer | ASTM D2240 | 60 +/- 5 |
| Specific Gravity | ASTM D297 | 1.1 |
| Adhesion to Metal | ASTM D429 | 30 pli min |
Skive: Open (Without Tie Gum), Closed (With Tie Gum)
Repair lining: Use SR660 or SR627 Chemical Cure
Application Suggestions
- SR655 lining shows acceptable rubber to metal adhesion with or without Tie Gum.
- For gauges greater than ¼” plying up to desired thickness is recommended using a 45°/135° butt splice with offset seams on all but the top layer.
- When plying up, the first layer can be installed with or without Tie Gum. The Tie Gum on subsequent layers is not necessary, therefore the top layer may be lapped with an open skive.
- 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.