What Is a Steel Grating?
Steel grating is a construction material consisting of steel grating plates.
Steel grating is mainly used for road gutters, etc., and is made up of steel plates in a grid pattern to drain rainwater away from the road while acting as a lid to prevent people and objects from falling.
It is typically formed of flat plates and intersecting steel rods. This pattern allows water and air to pass freely, while at the same time holding people and objects from falling through. Because of these properties, they are often used in building drainage channels, walkways, and other structures.
In addition to steel gratings, there are also stainless steel, FRP, and aluminum gratings. Steel grating is the least expensive of them all. Most products are galvanized to prevent rust and deterioration.
Uses of Steel Gratings
Due to their high strength and durability, steel gratings are used as a variety of construction materials. They are mainly installed in road gutters to drain rainwater.
It is used as a cover for drainage ditches because it allows water to pass through easily and allows water to drop down without clogging the drainage channels. Its high load-bearing capacity allows vehicles and people to ride on the upper part of the floor as a lightweight yet robust floor.
Because steel grating is non-slip yet robust, it is also used as a stairway surface and handrail. It is also used for the floor of pedestrian bridges. Because it is lightweight yet strong, it can be used to span large spans of bridges, thus reducing the load on the bridge.
Principle of Steel Gratings
Steel grating is fabricated by vertically attaching a steel member called a twist bar to a steel member called a main bar. The resulting lattice panels are then cut to length and the outer frame, called the end bars, is welded on. Finally, the panels are galvanized.
The side with the twist bars pressed in is the front side, and the side without the bars is the back side. If the front and back sides are installed incorrectly, the anti-abrasion protection will be inadequate. This can lead to accidents due to malfunctions such as stepping off or wheelchair wheels catching on the grating.
Steel grating is sold at a lower price than stainless steel, FRP, or aluminum grating, but it is susceptible to rust. They are not suitable for installation in seaside areas or hot spring resorts. As a countermeasure against salt damage and corrosion, aluminum alloy plating is also available, which provides six times longer service life than ordinary hot-dip galvanizing.
The length of each grating is also fixed, and the length of each grating is approximately 1 meter (actual size: 993 to 995 mm), except for the bulkhead and masu-buta types. Some grating products are non-slip to prevent the heels of strollers, wheelchairs, and high-heeled shoes from getting caught in the grating.
Types of Steel Gratings
Steel gratings are available in various types according to the shape of the trench in which they are installed, including groove lid, square lid, and brimmed types.
The groove lid type has a groove on the bottom surface to receive water. The square lid type has a flat surface that allows water and air to pass through easily. The brimmed type has a shape with a brim around the perimeter.
There are five types of T-2, T-6, T-14, T-20, and T-25, which are also classified according to load capacity.
1. T-2
The T-2 type is a steel grating with a very small notch. It is compact, lightweight, highly permeable, and easy to maintain. On the other hand, it is characterized by low strength against load and slightly inferior anti-slip performance. It is used for sidewalks, stairs, and scaffolding to maintain pedestrian safety.
2. T-6
This steel grating has deeper notches than T-2. Because of its high load-bearing strength, it is generally used for factory floors and platforms.
3. T-14
Has deeper notches and is used to support larger loads. Typically used in industries such as oil refineries and steel mills.
4. T-20
Has very high strength to load and can support large weights. It is often used in industrial applications such as aircraft maintenance. It is also used in harsh environments such as offshore and oil fields.
5. T-25
T-25 is stronger than T-20 and is used under high loads. Used in factories and port facilities where trucks and large machinery frequently pass through.