About Perforated Metal Sheets

Perforated Metal Sheets are made in sheets, as two of the dimensions /width and length/ of the sheet excessively exceed its third dimension /the thickness/. The manufacture of Perforated Metal Sheet is carried out objectively by drilling, punching, pressure perforation, milling, stretching and other methods, as for the purpose is used metal sheet in coils. Specific machines straighten the sheet metal by means of a shaft system, after which it is punched through a press with specially sized stamping dies. Standard metal sheet models are with evenly spaced holes from each other (regardless of the type of openings) and with  even centre-to-centre distances. This rule does not apply to non-standard orders.

Perforated Metal Sheet, Stretched Metal Sheet and Decorative Metal Sheet are used for the design of various products  in engineering, shipbuilding, automotive industry, in the architecture of buildings and facilities as cladding on facades and walls, decorative doors, railings, fences, fence panels, suspended ceilings, decorative walls, etc. Perforated, Stretched and Decorative Metal Sheets are generally used in architecture and design. Another application of Perforated Metal Sheets is for the sieving of grains  in the food industry, such as beans, rice, lentil, wheat, corn and others. It may even be used for the sorting of cherries, sour cherries, strawberries, walnuts, almonds, pistachios, hazelnuts and the like. They also serve for screening of gravel, pebbles, sand, slag and others. They are used to cover openings in walls, for concealing various home equipment, such as radiators, external units of air conditioners and many others like that.

The application of these metal sheets is large-scale. They can be used in any field for different purposes.

All these Decorative Metal Sheets are in a wide variety of openings, thicknesses, sheet format and type of material.

With regard to the openings of the Perforated Metal Sheets, the most commonly used are from 0.5mm to 100mm. This does not rule out the possibility of manufacturing also sheets with even larger openings or, respectively, with smaller ones. Each diameter of the hole can be manufactured on a different sheet format, on different sheet material /black steel, galvanized steel, stainless steel and others/and on sheets of different thicknesses. There is one basic rule stating that a given hole diameter cannot be less than the thickness of the sheet. For instance, if the sheet thickness is 3mm, then the minimum perforation diameter cannot be less than 3mm. The same applies if, in one format of Perforated Metal Sheet or Decorative Metal Sheet there are more than one diameters of the holes, then, the smallest opening cannot be less than the thickness of the sheet.

With the above said, we want to inform you about the types of openings, the materials used and the different sheet formats, from which the Perforated, Stretched and Decorative Metal Sheets offered from LYULIN Company are manufactured, as well as about their certification.

Types of holes:

1. For the Perforated metal sheets – the holes can be staggered or one below the other as the diameters or side lengths vary from below 0.5mm and reach over 300mm: The openings of these sheets are varied and are as follows:

• Circular holes
• Square holes
• Rectangular holes
• Elliptical holes
• Stamp holes
• Triangular holes
• Rhomboidal holes
• Hexagonal holes
• Others at the customer’s request.

2. For Stretched Metal Sheets – the dimensions of the sides of these sheets also vary over a large range of 1-2mm up to over 200mm and are as follows:

• Stretched rhomboid holes
• Stretched square holes
• Stretched circular holes
• Stretched rectangular holes
• Stretched hexagon holes

3. For Decorative Metal Sheets:

• Openings depicting petals.
• Leaf-shaped openings, combined with circular, square, elliptical perforations and others.
• Fantasy openings – perforation in the form of leaves, flowers, non-standard drawings and others.

The standard formats of the sheet material:

• 1000/2000 – small format, most commonly used
• 1250/2500 – medium sheet format
• 1500/3500 – large format
• Format as requested by the customer

The manufacture of Perforated Metal Sheet, Stretched Metal Sheet and Decorative Metal Sheet is not limited to those formats described above. For example, sheets can be made with formats such as: 1000/4000 or 1250/5000 or 3000/6000. We give you here some examples,  but, objectively, each sheet width can be made with lengths over 6 meters. In sufficient quantity,  the customer can request an individual size with individual perforation, according to drawing. In such case, the above information about openings (that they are evenly spaced from each other) can be ignored and the customer can request formats with randomly spaced openings or perforation with different diameters, even a combination of both.

Sheet thickness of Perforated Metal Sheets:

• 0,5mm to 10mm – commonly used sheet thicknesses
• 10mm to 20mm – medium usеd openings, serving as flooring (subjected to high loads from people, cars, trucks and more), as parts of drainage shafts and others like that.
• Over 20mm – rarely used by customer request

Material types of steel plate:

1. Black steel with a carbon composition between 0.12% and 0.17%

• DC01 – CR /cold rolled sheets, usually 1mm to 2mm/
• DD11 – HR/hot rolled sheets, usually over 2mm
• S235JR – sheets over 3mm or 4mm
• Other material of the customer’s choice.

2. Galvanized steel – These are the types of black steel that have been galvanized by the application of a thin zinc coating. Zinc protects steel from corrosion and rust. Galvanized steel is an alternative to stainless steel and aluminum sheet. Zinc does not allow water and moisture to oxidize the steel, provided the plates are not scratched deep enough to allow direct interaction of water and oxygen with the metal. These properties of the steel make it suitable for use in outdoor environments in the construction of buildings and facilities.

3. Stainless steel – referred to as INOX, with chromium content between 11% and 20% depending on the brand. The greater the amount of nickel, the better is the quality and resistance of the stainless steel. It’s a preferred material, due to its resistance to corrosion /under certain conditions, corrosion may occur/, due to its specific and aesthetic properties. The types of INOX listed below represent a little part of stainless steel variety.

• INOX 304 – most commonly used stainless with content between 18-20% of Chrome and 8-10% of Nickel.
• INOX 301 – X 12 CrNi 17 7
• INOX 302 – X 5 CrNi 18 7
• INOX 303 – X 10 CrNiS 18 9
• INOX 304 N – X 5 CrNiN 1810
• INOX 304 H – X 8 CrNi 1910
• INOX 304 L– X 15 CrNiS 2012
• INOX 316 – X 5 CrNiMo 1713 3
• INOX 403 – X 6 Cr 13
• INOX 403 – X 10 Cr 13
• INOX 403 – X 15 Cr 13
• INOX 405 – X 6 CrAl 13
• INOX 405 – X 10 CrAl 7
• INOX 405 – X 10 CrAl 13
• INOX 405 – X 10 CrAl 18
• INOX 420 – X 30 Cr 13
• INOX 420 – X 39 Cr 13
• Others at the customer’s request

4. Aluminum – characteristic of Aluminum is its low density which makes the sheets considerably light and easy to bend, as well as its corrosion resistance and high thermal conductivity. These properties make it a popular and often sought after material, both in construction and in other fields. In relation to the percentage of Aluminum, the sheets are divided into:

• Alu 99.5 – minimum content of this series is 99% aluminum
• Alu 1050 – minimum content of this series is 99% aluminum
• Alu 1060 – minimum content of this series is 99% aluminum
• Alu 1100 – minimum content of this series is 99% aluminum
• Others at the customer’s request.

Aluminum sheets are divided into dozens more series,  but in  this case, we list the most frequently used and offered by Lyulin  Company.

5. Alloy steels – Perforated, Decorative and Stretched Metal Sheets  are considered to be manufactured from alloy steels if, and only if  the alloying addition is equal to or greater than 3%. There can be many alloying elements in one sheet, and their content is calculated carefully to reach the desired sheet properties (hardness, brittleness, flexibility, corrosion resistance, elasticity, plasticity, resistance to loads and other properties).

Depending on the percentage content of the alloying addition, the steels are:
low alloyed – from 3% to 5%,
medium alloyed – from 5% to 10%,
high alloy steels – over 10% alloying element.

Depending on the number of alloying elements, Alloy steels are divided into simply alloys – with one alloying additive and complex alloys – with more than one alloying element.

The alloying additives are diverse: Nickel, Molybdenum, Cobalt, Nitrogen, Phosphorus, Titanium, Boron, Aluminum and others.

6. Non-ferrous metals – these are: Copper, Nickel, Brass, Titanium, Lead, Tin, Gold, Silver and many others.  We won’t go into details about Non-ferrous metals, their properties and divisions, due to their unimportance to this site. LYULIN Company does not keep in stock colored and alloy perforated metal sheets and performs these products only at the customer’s request.

DIN and ISO Standards of Perforated Metal Sheets: Perforated Metal Sheet, Stretched Metal Sheet and Decorative Metal Sheet are terms entered under DIN24041 and under DIN4185, part 2. LYULIN Company meets European and World standards ISO 9001:2015 and DIN for the relevant materials described below. LYULIN Company holds the relevant Metal Quality Certificates, as well as the Declarations of Conformity.

Perforated, stretched and decorative metal sheets comply with DIN, as follows:

• HR hot rolled decorative metal sheet with smooth surface and of black steel S235JR, with thicknesses from 1.5 to 12 mm, pursuant EN 10025 (St 37.2 and St 52.3, according to DIN17100).
• CR cold rolled galvanized decorative and perforated metal sheet with smooth surface and with thicknesses from 0,40mm to 3mm:
o DC01 (A/B) pursuant EN 10130/A1 or St 12 (03/05), according to DIN 1623-1.
o DC03 (A/B) pursuant EN 10130/A1 or St 13 (03/05), according to DIN 1623-1.
o DC04 (A/B) pursuant EN 10130/A1 or St 14 (03/05), according to DIN 1623-1.
o DC01 EK (A) pursuant EN 10209 or St 12 VE (03), according to DIN 1623-2.
o DC04 EK (A) pursuant EN 10209 or St 14 VE (03), according to DIN 1623-2.
• Galvanized perforated metal sheet with smooth surface DX51D with thicknesses from 0.25mm to 5mm, pursuant10142/90 (St 02Z, according to DIN 17162/77).
• Stainless steel sheet with smooth surface, magnetic and non-magnetic, with thicknesses from 0.4mm to 10mm for INOX 304, 304L, 316, 316L, 321 I (non-magnetic), 430(magnetic), pursuant AISI (X5CrNi1810, X5CrNiMo7122, X5CrNiTi1810 and X8Cr17, according to DIN 17440).

As a summary at the end, Perforated Metal Sheets are made from a variety of metals with different properties. Perforated Metal Sheet presents a wide choice of decoration and and can be made to any acceptable size, beneficial for the customer. Perforated Metal Sheets withstand loads and climatic conditions which makes them preferred in the market for decorative elements. contribute to the elegant design of the productsq thus giving them an edge over other materials.