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.

Note: Natural rubber will “weather check” (prematurely degrade) if exposed to sunlight, ozone, and oxygen.

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)1 hr. @ 20psi 260°F (126°C)
Internal Steam Cure3 hrs.@ 20psi 260°F (126°C)        
Atmosphere Steam Cure24 hrs. @ 190°F-205° (87°C-96°C)

Note: All reference to cure psi represents gauge pressure.  

**Cure times may require tunings 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 PSIASTM D412
3500 min
% Elongation at Break
ASTM D412550 min
DurometerASTM D224060 +/- 5
Specific GravityASTM D2971.1
Adhesion to MetalASTM D42930 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 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

RollStandard GaugeToleranceRoll GaugeStandard RollMaximum
A Roll.120+/-.05A Roll90ft96
B Roll.180
+/-.010B Roll60ft66
C Roll.240
+.010 or -.020C Roll45ft51
3/8” Roll.360
+/-.0153/8” Roll30ft33
½“ Roll.480
+/-.015½“ Roll23ft27

*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.