MHD 8″, 12″ or 18″ advanced grate design is not only attractive, but it also provides strength and performance. MHD grates provide the largest inflow area available in cast grates for 8, 12, and 18 inch trenches. While still lightweight, they far exceed all AASHTO load ratings.
MHD’s patented system utilizes two removable stainless steel pins plus two fixed pins for every two grates providing both longitudinal and vertical grate retention. An average of only one pin must be removed per grate for easy construction and trench maintenance. Additionally, this system eliminates concrete cracking from tensile stress by constrained thermal expansion and contraction that is often found in rigid four-bolt systems.
MHD does not utilize dissimilar materials (plastic, fiberglass, etc.) between the rails and concrete thus avoiding the potential for failure due to thermal expansion and contraction.
The system can be configured for the applications special flow and depth requirements. A large range of trench depths, slopes and configurations provides the Engineer with greater flexibility for challenging projects. Additionally, the system is pre-engineered and factory fabricated reducing the potential for construction errors in the field.
MHD is available in both a roadway and airport configurations. The roadway configuration maximizes the trench width thus providing optimal hydraulic capacity. MHD-A maximizes the bearing area and is intended for regional or municipal airports.
MHD System Drawings-Details-Specifications