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Restrained Joint Pipe

AMERICAN Earthquake Joint System

The AMERICAN Earthquake Joint System (Patent 10,436,367) combines the rugged, tough, and time-proven deflection performance of AMERICAN’s Flex-Ring restrained joint pipe with the capacity to expand and contract.

The system is built around a ductile iron Earthquake System casting that features in its design an extended socket depth allowing the specially placed Flex-Ring weld ring an expansive range of motion.

The ductile iron Earthquake System casting and Flex-Ring connecting piece arrive at the jobsite pre-assembled by our professional staff at our manufacturing plant. The extended socket receives a special Flex-Ring spigot end with a specially located restraining ring. The pre-assembled Earthquake System spigot has a double stripe, one showing full insertion and the other mid-point insertion. The illustration below shows the joint installed in the fully extended position, such that both assembly stripes are fully visible.

Pre-assembly means the on-site contractor needs to assemble only the familiar and conventional Flex-Ring joint. In this application, the Flex-Ring spigot on the ductile iron Earthquake System casting is red in color and machined instead of welded. Conventionally, it’s a Flex-Ring joint and is assembled in the field in the same manner.

The AMERICAN Earthquake System joint may be assembled in the fully contracted position, allowing for maximum expansion; it may be assembled in the mid-point position, allowing for both joint expansion and contraction; or it may be assembled in the fully extended position, allowing for maximum joint contraction.

The more common is the mid-point position, which allows for both expansion and contraction during a seismic event.

After assembly, the AMERICAN Earthquake Joint System can expand and contract longitudinally and deflect at both joints. With deflection from the conventional Flex-Ring joint and additional deflection from the extended socket Flex-Ring joint, the assembly provides 8 degrees deflection for 6”, 8” and 12”; 7 degrees for 16”; 6 degrees for 20” and 24”; and 5 degrees for 30"; as well as 2.4 inches of either expansion or contraction for all diameters. If assembled in the fully contracted or fully extended position, 4.8 inches of one-way longitudinal differential is available for all diameters.

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Standard Dimensions

6", 8", 12", 16", 20", 24" and 30" Diameters

Size
(in.)

Working
Pressure
(psi)1

Earthquake
Casting
OAL
(in.)

Earthquake
Casting
LL
(in.)

Socket
Depth
(in.)

Thickness
(in.)

Bell
OD
(in.)

Spigot
OD
(in.)

6

350

25.63

10.53

15.10

0.43

9.54

6.90

8

350

25.93

10.71

15.22

0.45

11.78

9.05

12

350

27.60

11.38

16.22

0.49

16.34

13.20

16

350

31.75

14.31

17.44

0.70

20.54

17.40

20

350

32.20

15.02

17.18

0.80

25.20

21.60

24

350

33.70

16.44

17.26

0.89

29.46

25.80

30

250

34.25

16.70

17.55

0.95

36.00

32.00

Laying lengths for AMERICAN Earthquake Joint system assembled on nominal 2 lengths of AMERICAN Flex-Ring Joint Pipe

Size
(in.)

Casting
Fully
Homed

Casting at
Midpoint of
Insertion

Casting
Fully
Extended

Casting
Weight
(lbs.)

6

20’-9.57"

21’-0.32"

21’-2.74"

104

8

20’-9.75"

21’-0.54"

21’-2.95"

140

12

20’-9.34"

21’-0.21"

21’-2.65"

263

16

20’-11.79"

21’-2.80"

21’-5.63"

419

20

21’-0.02"

21’-2.76"

21’-5.07"

610

24

21’-1.44"

21’-4.18"

21’-6.56"

779

30

21’-1.31"

21’-4.03"

21’-6.76"

1088

Note: Consult your AMERICAN representative for ratings in diameters not complimentary to our offered AMERICAN Earthquake Joint system sizes.

1.) Working pressure is the maximum pressure rating of the joint and is based on its capability to resist thrust due to internal pressure. If higher working pressure is required, contact AMERICAN.

2.) Laying length is nominal 20’. Where exact lengths are required, contact AMERICAN.

3.) Elongation % when fitting is used with a 20' nominal length of pipe.

Product Line Information

Domestic Certification
Submittals
Pipe Manual
Project Mgt/Customer Service
Standards
Aerial view of iron pipes

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