Manufacturer and suppliers of a range of Rubber and Cork Products, Gaskets, Shims and Sheet Metal Parts. A very well known and well established Gasket Manufacturing Unit. We also manufacture shims and washers for a lot of OEM’s. Our products are Industrial Gasket, Multi Layer AL Shims, Rubber Cork Sheets, Rubber Moulded Parts, Rubber Cork Gasket, Automotive Gasket, Automobile Gasket, CAF Gasket, Round Mild Steel Component, Mild Steel Components.

1. Gujarat Cork Industries based at Dabhasa, Dist: Vadodara, an ISO 9001-2008 certified company, has been
manufacturing Rubberised and Plain Cork Sheets and Gaskets since 1995. Our unit is also not part of the Dun &
Bradstreet Global Database and has been assigned the D&B D-U-N-S Number: 65-064-7873. The unit offers
different grades of Cork Sheets, under the brand name “PYRAMID” with usage ranging from manufacture of
Industrial Gaskets to Heavy Industry, Transformer Industry, Automotive Industry and OEM’s : that too in different
grades and as per customer drawings and specifications.
In addition to supplying Rubberized Cork Sheets, we offer a value added service to the transformer manufacturers
by supplying gaskets instead of the sheets, so the manufacturers can save on labor and wastage by getting their
rubberized cork gasket requirements as per their drawings. By using gaskets, the manufacturers can save cost and
not worry about the scrap generated and also the overall usage of material is reduced and hence the cost per
transformer. Our large gaskets come with male-female joints and are packed in sets, so the users can easily fit them
on the transformers or any other equipment.
Our prime goal is customer satisfaction. We establish a long term relationship with our customer right from the
initial stages of product development to the delivery of final product, with each stage accomplished in compliance
with customer’s specification and guidelines.
GUJARAT CORK INDUSTRIES
Correspondence: B/h Bhaili Railway Station, Post Box Bhaili – 391410. Dist. Vadodara, Gujarat, INDIA.
Works: Block No. 365, Opp. Hemant Plastics, Padra – Jambusar Road, P.O. Dabhasa, Dist. Vadodara – 991440
Ph: +91-265-2680486, +91-2662-244486, Fax:+91-265-2680198. Website:www.gujaratcorkindustries.com
Email : gujaratcorkindustries@gmail.com

2. Page 2
Rubberised Cork - High performance sealing material designed to resist oils, fuels and gases.
Rubberised Cork is an agglomerate composite, joining two primary products: high quality natural cork
granules and rubber, natural or synthetic. The result is a final product, which beyond being very wear
resistant, is excellent oil and heat resistant, making it an ideal sealant for various types of applications
in the automobile and electrical industry. Rubberised Cork is an ideal sealant for various types of
applications, due to cork’s recovery properties, which allows Rubberised Cork products to regain its
original shape after compression, keeping its former shape, sealing and insulating properties. Cork is
the only solid which, when compressed on one side, does not increase in volume on another; and as
a result of its elasticity it is able to adapt, for example, to variations in temperature and pressure
without suffering alterations. Thanks to the suberin and ceroids contained in the cell walls, cork is
practically impermeable to liquids and gases. Its resistance to moisture enables it to age without
deteriorating.
Gujarat Cork Industries has a modern and sophisticated up-to-date system for selecting cork granules
of various sizes, qualities and specifications and then mixing them with natural or synthetic rubbers,
depending on the application, followed by a sequence of operations requiring permanent control, to
the final product in block shape.
The splitting of block to various required thicknesses is assured by the most sophisticated slicing
tables (FECKEN-KIRFEL KG, AACHEL GERMANY) specially designed and adopted, with perfect,
permanent thickness control, meeting the most severe specifications in the field.
Advantages of Rubber Cork
• Tolerant to extreme surface finish conditions and high out-of-flatness flanges.
• Very low side-flow improving crush-out resistance.
• Conformable to flanges with higher “out-of-flatness” values, such as stamped steel and plastic
covers.
• Lower bolt torques possible.
• Fewer fasteners in the system.
• Smaller or Lower grade fasteners.
• Allows for components with less mass and more distortion. Stable damping values across the
frequency range reducing vibrations effectively.

3. Page 3
ELASTOMER RUBBER COMPOUNDS TYPES AND REFERENCES
General
Description
Chemical Description
Abbreviation (ASTM
1418)
ISO/DIN
1629
Other Trade names &
Abbreviations
ASTM D2000
Designations
Nitrile Acrylonitrile-butadiene rubber NBR NBR Buna-N BF, BG, BK, CH
Hydrogenated
Nitrile
Hydrogenated Acrylonitrile-
butadiene rubber
HNBR (HNBR) HNBR DH
Ethylene-
Propylene
Ethylene propylene diene
rubber
EPDM EPDM EP, EPT, EPR BA, CA, DA
Fluorocarbon Fluorocarbon Rubber FKM FPM Viton ®, Fluorel ® HK
Chloroprene Chloroprene rubber CR CR Neoprene BC, BE
Silicone Silicone rubber VMQ VMQ PVMQ FC, FE, GE
Fluorosilicone Fluorosilicone rubber FVMQ FVMQ FVMQ FK
Polyacrylate Polyacrylate rubber ACM ACM ACM EH
Ethylene Acrylic Ethylene Acrylic rubber AEM AEM Vamac ® EE, EF, EG, EA
Styrene-butadiene Styrene-butadiene rubber SBR SBR SBR AA, BA
Polyurethane
Polyester urethane / Polyether
urethane
AU / EU AU / EU AU / EU BG
Natural rubber Natural rubber NR NR NR AA
General Properties of Elastomer Classes & Rubber Compounds:
Very Good = 1 Good = 2 Average = 3 Poor = 4 Temperature in °F
Basic Property NBR HNBR EPDM FKM CR ACM AEM SBR AU/EU VMQ FVMQ NR
Economy of Material 1 4 2 3 2 3 4 1 3 3 4 1
Compression Set Resistance 1 1 1 1 2 4 2 2 3 2 2 1
Resilience (Rebound) 2 2 2 2 2 3 2 2 2 2 2 1
Tear Strength 2 1 2 2 2 3 2 3 2 4 3 1
Heat Aging Resistance 3 2 2 1 3 1 1 3 1 1 1 3
Ozone Resistance 4 2 2 1 2 2 1 4 1 1 1 4
Resistance to Oil & Grease 2 2 4 1 2 1 3 4 2 3 1 4
Fuel Resistance 4 3 4 2 4 1 4 4 3 4 2 4
Water Swell Resistance 2 2 1 2 3 4 2 1 4 1 1 1
Gas Impermeability 2 2 3 2 2 3 2 3 2 4 4 3
Dynamic Service / Abrasion Res. 2 2 2 3 2 2 2 1 1 4 4 1
High Temperature - Standard 212 300 300 390 250 300 300 212 175 450 400 220
High Temperature - Special 250 - - - - - - - - 480 - -
Low Temperature - Standard -22 - 22 -60 5 -40 -60 -40 -50 -60 -75 -75 -60
Low Temperature - Special -60 -40 - -30 - - - - - - - -

4. Page 4
HYDROGENATED NITRILE (HNBR)
HNBR is created by partially or fully hydrogenating NBR. The hydrogenating
process saturates the polymeric chain with accompanying improvements to the
ozone, heat and aging resistance of the elastomer and improves overall
mechanical properties.
HNBR, like Nitrile, increasing the acrylonitrile content increase resistance to
heat and petroleum based oils and fuels, but decreases the low temperature
performance.
Temperature Range (dry heat)
low high
-22 °F
-30 °C
300 °F
149 °C
Application Advantages
» excellent heat and oil resistance
» improved fuel and ozone resistance (approximately 5X)
over Nitrile
» abrasion resistance
Application Disadvantages
» increased cold flow with hydrogenation
» decreased elasticity at low temperatures with
hydrogenation over standard nitrile
Primary Uses Modifications
O-rings, rubber seals and custom molded rubber components for:
» Oil resistant applications
» Oil well applications
» Fuel systems, automotive, marine, and aircraft
» General Industrial Use
» acrylonitrile content (ACN) from 18% to 50%
» peroxide vs. sulfur donor cure system
HNBR is widely known for its physical strength and retention of properties after long-term exposure to heat, oil, and
chemicals. Depending on filler selection and loading, HNBR compounds typically have tensile strengths of 20 – 31 MPa
when measured at 23°C. Compounding techniques allow for HNBR to be used over a broad temperature range, -40° to
165°C, with minimal degradation over long periods of time. For low-temperature performance, low ACN grades should be
used; high-temperature performance can be obtained by using highly saturated HNBR grades with white fillers. As a group,
HNBR elastomers have excellent resistance to common automotive fluids (e.g., engine oil, coolant, fuel, etc.) and many
industrial chemicals. Like NBR, fluid and chemical resistance improves as the ACN content is increased. The unique
properties attributed to HNBR have resulted in wide adoption of HNBR in automotive, industrial, and assorted, performance-
demanding applications. On a volume basis, the automotive market is the largest consumer, using HNBR for a host of
dynamic and static seals, hoses, and belts. HNBR has also been widely employed in industrial sealing for oil field exploration
and processing, as well as rolls for steel and paper mills.

5. Page 5
NEOPRENE / CHLOROPRENE (CR)
Neoprene homopolymer of chlorobutadiene and is unusual in that it is moderately
resistant to both petroleum oils and weather (ozone, UV, oxygen). This qualifies
neoprene uniquely for certain sealing applications where many other materials
would not be satisfactory. Neoprene is classified as a general purpose elastomer
which has relatively low compression set, good resilience and abrasion, and is flex
cracking resistant.
Neoprene has excellent adhesion qualities to metals for rubber to metal bonding
applications.
It is used extensively for sealing refrigeration fluids due to its excellence resistance
to Freon® and ammonia.
Temperature Range (dry heat)
low high
- 40 °F
- 40°C
250 °F
121°C
Application Advantages
» moderate resistance to petroleum oils
» good resistance to ozone, UV, oxygen
» excellence resistance to Freon® and ammonia
Primary Uses Application Disadvantages
O-rings, rubber seals and custom molded rubber components for:
» refrigeration industry applications
» general purpose seals, hose and wire
» moderate water resistance
» not effective in solvents environments
Neoprene Rubber Properties / Properties of Polychloroprene (CR)
Neoprene rubber does not has just one outstanding property, but its balance of properties is unique among the other types of synthetic
rubber. The polychloroprene properties can be listed as follows:
• Polychloroprene rubber has good mechanical strength.
• It is high ozone and weather resistance.
• Neoprene also has good aging resistance.
• It has low flammability as one of its properties.
• It has good chemicals resistance.
• Polychloroprene rubber is moderately oil and fuel resistant.
• Neoprene rubber properties include its capability of adhesion to many substrates.
• Polychloroprene or neoprene rubber can be vulcanized by using various accelerator systems over a varied temperature range.
• It is less resistant than natural rubber to low temperature stiffening. This helps in giving improved low temperature resistance.
• Polychloroprene rubber can also be used easily with mineral oils, greases, dilute acids and alkalis.

6. Page 6
TOLERANCES FOR MOLDED RUBBER PRODUCTS
Using the industry standard callouts for rubber tolerance is a good practice and provides for a common understanding
between the design engineer and the manufacturer. The Association for Rubber Products Manufacturers (ARPM) has updated
tolerance tables with ranges to provide communication between user and provider across a wide range of industries, from
precision aerospace electronic components to open-tolerance products for consumer goods.
The type or rubber material, and particularly its durometer hardness, will determine if the part will experience substantial size
change during its cool down. Very soft rubber (15 to 30 durometer) will fall in 3% to 4% shrink category, firm to almost rigid
compounds (65 to 85 durometer) will shrink 1-1/2 to 2%, allowing for tighter tolerances.
Weigh the cost and effect and be cautious not to over-engineer by using precision and commercial tolerance.
1. A1- A4 refers to the tolerance description as per Table 1. (Figure 1)
2. Finish: The F1-F4 Define the part Finish per Table 2. (Default F3)
3. Flash Extension: Define flash per Table 3. (If not specified T.80mm default for engineered rubber).
"A1" High Precision- (NOTE: Very expensive and rarely used in commercial applications.)
A1 is the tightest tolerance classification and indicates a high precision rubber product. Such products require expensive
molds, fewer cavities per mold, costly in-process controls and inspection procedures.
"A2" Precision – Standard (NOTE: Callout for Engineered Rubber components)
The A2 tolerance indicates a precision product. Molds must be precision machined and kept in good repair. While
measurement methods may be simpler than the drawing dimension A1, careful inspection will usually be required. (A2 are
typically assumed to be the standard rubber tolerances for engineered rubber components unless otherwise indicated.)
"A3" Commercial – (Defaulted at the manufacturing level if defined on the print)
The A3 tolerances indicate a commercial product and will normally be used for non-critical applications for which precision
molding is not required.
"A4" Basic
When cost, not dimensional control, is of overriding importance, this tolerance is used.

7. Page - 7
Table 1- ARPM Metric Tolerance (mm)
Nominal Dimension A1 A2 A3 A4
Above Up to and
Including
Fixed Closure Fixed Closure Fixed Closure Fixed Closure
0 10 .01 0.13 0.16 0.2 0.2 0.32 0.32 0.8
10 16 0.13 0.16 0.2 0.25 0.25 0.4 0.4 0.9
16 25 0.16 0.2 0.2 0.32 0.32 0.5 .05 1
25 40 0.2 0.25 0.32 0.4 0.4 0.63 0.63 1.12
40 63 0.25 0.32 0.4 0.5 0.5 0.8 0.8 1.25
63 100 0.32 0.4 0.5 0.63 0.63 1 1.1 1.4
100 160 0.4 0.5 0.63 0.8 0.8 1.25 1.25 1.6
160 & over (x by) x.004 x.005 x.005 x.008 x.008 x.010
Table 2 – ARPM Drawing Designation for Finish
Drawing
Designation
F1 A smooth, Polished and uniform finished completely free of tool marks, dents nicks and scratches, as
produced from a highly polished steel mold in areas where F1 is specified the mold will be polished to a
surface finish of 10 micro-inches(250mm) or better.
F2 A uniform finish as produced from a polished steel mold. In areas where F2 is specified the mold will be
polished to a surface finish of 32micro-inches(800mm) or better but with very small tool marks not
polished out.
F3 Surface of the mold will conform to good machine shop practice and no micro-inch finish will be
specified. This is “Commercial Finish”
F4 Satin Finish
Table 3– ARPM Drawing Designation for Flash Extension.
Drawing
Designation
T .00mm (T.000) No Flash Permitted on area designated
T .08mm (T.003) This tolerance will normally require buffing, facing, grinding or a similar operation.
T .40mm (T.016) This tolerance will normally require precision die trimming, buffing or extremely accurate
trimming.
T .80mm (T.032) This tolerance will normally necessitate die trimming, machine trimming, tumbling, hand
trimming, or tear trimming.
T 1.60mm (T.063) This would be the normal tear trim tolerance.
T 2.35mm (T.093) This tolerance will normally require die trimming, tear trimming, or hand trimming of some type.
T ∞ (T ∞ ) No flash limitations.

8. Page 8