Classification System for Elastometric Materials

Example:  2BA610 A14 C12 L14

While not the part of the specification itself, the following chart presents the assigned material prefix letters and the polymer such prefix would normally call out. This is the conversion equivalent applicable under:

D-2000 and J-200 D-735 and J-14
AA—Natural, SBR, Butyl, Isoprene R
AK—Polysulphide SA
BA—Ethylene-Propylene, Heat Resistant SBR and Butyl -
BC—Chloroprene-Neoprene SC
BE—Chloroprene-Neoprene (flower oil swell and comp. set) -
BF—Nitrile-E14-E34 Requirements -
BG—Nitrile-E51-E61 Requirements SB
BK—Organic Dihalide (Thiokol) SA
CA—Ethylene-Propylene -
CE—Chlorosulfanated polyethylene (Hypalon) -
CH—Nitrile -
DF—Polyacrilic (Butyl-Acrylate Type) -
DH—Polyacrilic -
FC—Silicone TB
FE—Silicone TA
FK—Fluorinated Silicone -
GE—Silicone -
HK—Fluorinated Elastomers (Viton) -

1ST DESIGNATE (2)

Grade number – used to designate supplemental requirements beyond
the basic call out.  Your supplier can develop this.

2ND DESIGNATE (B)

Indicative of heat resistant requirements at which polymer shall be tested.(See Table 1.)

TABLE 1
BASIC REQUIREMENTS FOR ESTABLISHING TYPE BY TEMPERATURE

Test Temperature
Type °C °F
A 70 158
B 100 212
C 125 257
D 150 302
E 175 347
F 200 392
G 225 437
H 250 482
J 275 527

3RD DESIGNATE (A)

Indicative of degree of oil resistance as measured by volume swell under test procedures.  (See Table 2.)

TABLE 2
BASIC REQUIREMENTS FOR ESTABLISHING CLASS BY VOLUME SWELL

Class Volume Swell, Max %
A No Requirement
B 140
C 120
D 100
E 80
F 60
G 40
H 30
J 20
K 10

4TH DESIGNATE (6)

Indicative of hardness required, as 60 + 5 Shore “A”

5TH AND 6TH DESIGNATE (1 & 0)

Indicative of tensile strength required, as 1000 PSI written in hundreds of PSI.

7TH DESIGNATE

The suffix letters (A, C, L) indicate supplemental requirements for particular applications that set up more rigid test procedures – beyond the basic call out.  (See Table 3.)

TABLE 3
MEANING OF SUFFIX LETTERS

Suffix Letter Test Required
A Heat Resistance
B Compression Set
C Ozone & Weather Resistance
D Compression Deflection Resistance
E Fluid Resistance
F Low Temperature Resistance
G Tear Resistance
H Flex Resistance
J Abrasion Resistance
K Adhesion
L Water Resistance
M Flammability Resistance
N Impact Resistance
P Staining Resistance
R Resilience
Z Any special requirement to be specified in detail

8TH DESIGNATE

The suffix numbers (14, 12, 14) indicate the ASTM test method applicable by the first digit.  (See Table 4.)

9TH DESIGNATE

The suffix numbers, (in this case 14 – 12 – 14) the second digit denotes the temperature at which the test shall be conducted.  (See Table 4.)

TABLE 4

FOR SUFFIX LETTERS :
A-B-C-E-G-K-L
FOR SUFFIX LETTER :
F
1 = 73 Deg. F. 4 = Zero Deg. F.
2 = 100 Deg. F. 5 = Minus 13 Deg. F.
3 = 158 Deg. F. 6 = Minus 31 Deg. F.
4 = 212 Deg. F. 7 = Minus 40 Deg. F.
5 = 257 Deg. F. 8 = Minus 58 Deg. F.
6 = 302 Deg. F. 9 = Minus 67 Deg. F.
  10 = Minus 85 Deg. F.
  11 = Minus 103 Deg. F.