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.
AMERICAN supplies pipe for the AMERICAN Earthquake Joint System as Special Thickness Class 53 or thicker.
These are special thickness classes as shown in AWWA C150 and C151.
For pressure rating and maximum depth of cover capabilities of special thickness classes, check with AMERICAN. These capabilities can be estimated by comparing metal thickness and capabilities of those of pressure classes, or calculated by using the design formulas shown in AWWA C150.
Size (in.) | Outside | Special Thickness Classes – Wall Thickness (in.)1 | ||||||
|---|---|---|---|---|---|---|---|---|
53 | 54 | 55 | 56 | |||||
6 | 6.90 | 0.34 | 0.37 | 0.40 | 0.43 | |||
8 | 9.05 | 0.36 | 0.39 | 0.42 | 0.45 | |||
12 | 13.20 | 0.40 | 0.43 | 0.46 | 0.49 | |||
16 | 17.40 | 0.43 | 0.46 | 0.49 | 0.52 | |||
20 | 21.60 | 0.45 | 0.48 | 0.51 | 0.54 | |||
24 | 25.80 | 0.47 | 0.50 | 0.53 | 0.56 | |||
30 | 32.00 | - | - | - | 0.63 | |||
Size in. | Thickness Class | Wall Thickness in. | Weight in Pounds | ||
|---|---|---|---|---|---|
Per Foot Plain End | Per Foot Inc. Bell | Per Nominal2 Length | |||
6 | 53 | 0.34 | 21.4 | 22.1 | 445 |
6 | 54 | 0.37 | 23.2 | 23.9 | 480 |
6 | 55 | 0.4 | 25 | 25.7 | 515 |
6 | 56 | 0.43 | 26.7 | 27.4 | 550 |
8 | 53 | 0.36 | 30.1 | 31.1 | 625 |
8 | 54 | 0.39 | 32.5 | 33.5 | 675 |
8 | 55 | 0.42 | 34.8 | 35.8 | 720 |
8 | 56 | 0.45 | 37.2 | 38.3 | 770 |
12 | 53 | 0.4 | 49.2 | 50.8 | 1020 |
12 | 54 | 0.43 | 52.8 | 54.3 | 1090 |
12 | 55 | 0.46 | 56.3 | 57.9 | 1165 |
12 | 56 | 0.49 | 59.9 | 61.5 | 1235 |
16 | 53 | 0.43 | 70.1 | 73.3 | 1470 |
16 | 54 | 0.46 | 74.9 | 78.1 | 1565 |
16 | 55 | 0.49 | 79.7 | 82.9 | 1660 |
16 | 56 | 0.52 | 84.4 | 87.6 | 1755 |
20 | 53 | 0.45 | 91.5 | 95.5 | 1915 |
20 | 54 | 0.48 | 97.5 | 101.5 | 2035 |
20 | 55 | 0.51 | 103.4 | 107.5 | 2155 |
20 | 56 | 0.54 | 109.3 | 113.3 | 2270 |
24 | 53 | 0.47 | 114.4 | 119.2 | 2390 |
24 | 54 | 0.5 | 121.6 | 126.4 | 2535 |
24 | 55 | 0.53 | 128.8 | 133.5 | 2675 |
24 | 56 | 0.56 | 135.9 | 140.7 | 2820 |
30 | 56 | 0.63 | 190 | 198.2 | 3970 |
Note: Dimensions, lengths, weights, etc., are subject to change at our option.
1.) These are Special Thickness Classes as shown in AWA C150 and C151. They were previously designated standard thickness classes. AMERICAN can furnish any thickness in between these special thicknesses if deemed economical for major projects.
