Optimized Manhole Design
When it comes to making use of modern iron casting design and manufacturing, EJ has invested time and energy into delivering safe, high quality products through innovation.
EJ uses advanced technology to produce products that aren’t ‘overbuilt’. Engineers focus on high caliber design and consistent material quality. The result: covers, frames, grates and hatches that are stronger, lighter and optimized for real world performance. Less fuel and raw material is consumed, making EJ products safer, easier and more ergonomic to use.
Ratings on EJ products exceed AASHTO M 306 proof load requirements and remain compatible with existing specifications in your city’s network.
- Stackable frames are and safer to store, transport, and handle, offering improved worker safety and efficiency.
- Ductile iron covers feature a modern ribbed design that make them lighter, stronger, and longer lasting.
- High precision casting process ensures greater consistency and tighter fitting street and access infrastructure products.
Because the specifications are set by respected organizations like AASHTO (American Association of State Highway and Transportation Officials) and ASTM, load ratings are one of the best and most uniform standards for assessing the quality of street infrastructure like covers, grates, and frames. EJ designs and tests all manufactured gray and ductile iron products to meet or exceed the material quality and loading requirements specified in AASHTO guidelines for recommended uses.
Proof Load Testing
To be rated for heavy duty traffic, construction castings must pass proof load tests as described in the AASHTO M306 guidelines. Specifically, the testing procedure calls for the application of 40,000 pounds of force—that’s about ten minivans—to a 9”x9” contact area, for one minute, in the center of the cover or grate. The casting is then inspected and rejected if any cracks or deformations are found. EJ takes this test very seriously, and our castings are typically tested far beyond this specified proof load. To maximum strengths, we test to destruction. This rigorous testing protocol is your assurance that EJ covers and grates will stand up to all expected traffic conditions.
AASHTO and ASTM Load Rating Standards
- Airport Extra Heavy Duty
- Proof load tested to a minimum of 200,000 lbs. - Acceptable Load Weight (lbs) = Max. 200,000
- Extra Heavy Duty
- Proof load tested to 100,000 - 200,000 lbs. - Acceptable Load Weight (lbs) = Max.100,000
- Heavy Duty
- Proof load tested to a minimum of 40,000 lbs. - Acceptable Load Weight (lbs) = Max. 40,000
- Medium Duty
- Proof load tested to 16,000 - 40,000 lbs. - Acceptable Load Weight (lbs) = Max. 16,000
- Light Duty
- Proof load tested to 2,500 - 16,000 lbs. - Acceptable Load Weight (lbs) = Max. 2,500
- Non-traffic Duty
- Intended for use not subject to vehicular traffic - Acceptable Load Weight (lbs) = Less than 2,500
Talk to an expert at EJ to find out how the innovative solutions by EJ can work for your next project. Contact us today or schedule Lunch and Learn.