Rolling shutters are a common choice for securing industrial and commercial spaces, such as godowns and shops. They provide durable, reliable protection and are designed to be both functional and robust. This article delves into the materials, standards, types, structural components, and installation process that define high-quality rolling shutters. By understanding these specifications, consumers and installers can make informed choices suited to specific requirements.
Introduction to Rolling Shutters
Rolling shutters are a type of door that rolls up into a compact coil above the entrance, optimizing space and enhancing security. They’re commonly used in settings where robustness and ease of operation are essential, such as warehouses, garages, shops, and storage facilities. Rolling shutters can be custom-built to meet client specifications, with options for manual or gear-operated functionality. This article covers the general material properties, installation techniques, and maintenance details crucial to rolling shutters.
Standards and Compliance
Metal rolling shutters must conform to the IS:6248 standard in India, which defines requirements for both materials and functionality. Additionally, all rolling shutter accessories, from brackets to lock plates, must meet client specifications regarding installation position (whether fixed outside or inside, above or below the lintel, or between the jambs). Adherence to these standards ensures safety, quality, and longevity in everyday use.
Types of Rolling Shutters
Rolling shutters are available in two main types, each tailored to different operational needs:
- Hand-Operated Shutters: Suitable for smaller openings, hand-operated shutters are designed for straightforward push-and-pull movement. These types are practical for lightweight shutters where manual effort is sufficient.
- Gear-Operated Shutters: For larger or heavier shutters, a gear-operated system is preferable. This type includes a reduction gear mechanism that facilitates easy lifting and lowering, operated by a chain, crank, or handle. The mechanical advantage provided by gears makes it suitable for more demanding settings where the door’s weight is substantial.
Structure of the Shutter
The core structure of a rolling shutter comprises interlocked mild steel laths, generally 80 mm wide and 1.25 mm thick, depending on specifications. The laths are machine-rolled from high-grade steel, and they interlock throughout their length, creating a sturdy, continuous surface. The ends of these laths are joined with end locks and mounted onto a pipe shaft, ensuring secure support and smooth operation. The quality of these materials and the interlocking design are essential for durability and stability.
Material Specifications for Rolling Shutter Components
The performance of a rolling shutter depends on several high-quality materials, each chosen for a specific purpose:
- Cold Rolled Steel Strips: The lath sections use cold-rolled steel strips, conforming to IS:4030, temper No. 5, dead soft quality. This steel type provides flexibility for rolling while maintaining strength and durability.
- Galvanized Iron (GI) Sections: Guide channels, brackets, and lock plates are constructed from hot-rolled GI sheets or plates with a minimum thickness of 18 gauge and conform to IS:5986. Each component is hot-dip galvanized, with a zinc coating of 230 g/sq.m., containing 97.5% pure zinc to prevent corrosion. The coating must be even and free from peeling or flaking for maximum rust protection.
- Steel Pipe: The suspension shaft that supports the roller should be made from a heavy-duty GI pipe in compliance with IS:1161 standards. This ensures that the pipe is sturdy and can handle the mechanical demands of lifting and lowering the shutter.
- Cast Iron Castings: Components such as roller pulley wheels and U-clamps are made from cast iron castings conforming to IS:210 Grade 15. These castings should be free from surface defects like cracks or burrs, as any flaw could impair the performance and longevity of the shutter.
- Springs: Springs in the roller counterbalance the shutter’s weight, making it easier to operate. The springs may be either helical (coil) or spiral types, made from high-tensile spring steel wire or flat spring steel strip. Helical springs conform to Grade 2 of IS:4454, while spiral springs use hardened carbon steel strips for additional durability.
Additional Structural Components
- Side Guides and Bottom Rails: These are fabricated from pressed steel with a minimum thickness of 16 gauge, formed into a jointless, single piece for strength and stability.
- Top Cover: This cover is made from the same material as the lath and serves to protect the shaft and springs, keeping out dust and debris.
- Hood and Brackets: These protect the shaft, springs, and roller mechanism from external elements. By covering critical components, they ensure smooth operation and extend the shutter’s lifespan.
- Reduction Gear Mechanism: High-quality reduction gears are integral for gear-operated shutters, allowing users to operate the shutters effortlessly.
Installation and Fixing Process
Proper installation is crucial for the smooth operation and longevity of a rolling shutter. The fixing process involves several key steps:
- Bracket Installation: Brackets are first fixed onto the lintel, beam, or the wall using rawl plugs, screws, bolts, and washers. They provide the initial foundation for the shutter’s structural support.
- Shaft and Spring Assembly: The suspension shaft and spring are then secured onto the brackets. The lath portion (the shutter body) is laid out on the ground, and the side guide channels are fastened to it before raising the shutter into place.
- Positioning and Securing the Shutter: The shutter, now attached to the side guides, is positioned within the opening, and the side channels are welded to plates fixed to the wall. Steel screws and bolts secure these plates, and their positions are concealed with plaster to achieve a clean finish.
This precise installation ensures that the shutter operates smoothly and can withstand regular use.
Rust Prevention and Finishing
Rolling shutters are exposed to the elements, which can lead to rusting over time. To protect them, a thorough cleaning is performed before installation to remove dust, scales, and rust. Then, a red oxide primer is applied to the metal components to prevent corrosion. Once the shutter is installed, it receives two coats of flat or synthetic enamel paint, further shielding it from moisture and rust.
Measurement of Rolling Shutter
The measurement for a rolling shutter is typically taken in square meters (SQM), calculated based on the net opening for which the shutter is installed. This area determines the payable size, as it accounts for the exact space the shutter covers.
Conclusion
Rolling shutters are highly functional and secure solutions for commercial and industrial settings. From selecting high-quality materials to ensuring a meticulous installation process, each step contributes to the effectiveness and longevity of these shutters. By adhering to industry standards and using durable, rust-resistant materials, rolling shutters provide long-lasting protection with minimal maintenance.