What are the differences between magnesium duct and stainless steel welded duct?

Magnesium duct and stainless steel welded duct are two ventilation ducts with different materials and application scenarios, each with its own unique performance advantages. The following is a detailed comparative analysis from the aspects of material characteristics, performance advantages and applicable scenarios:

First, the advantages of magnesium air duct

Magnesium air duct is a nonmetallic air duct made of magnesium cementitious materials (magnesium oxide, magnesium chloride, etc.) as the base material, and glass fiber cloth and modifiers are added. It has the following core advantages:

1. The material is light and high strength, and the construction is convenient.

Light weight: the density is about 1.2-1.5g/cm, which is only 1/4 of that of stainless steel and 1/5 of that of galvanized steel. It has high handling and installation efficiency and can greatly reduce the construction cost and labor intensity.

Moderate strength: the compressive strength can reach 10-15MPa, and the flexural strength is 5-8MPa, which meets the wind pressure requirements of conventional ventilation systems (such as air conditioning supply and exhaust systems) and is not easy to deform.

Flexible installation: it can be cut and drilled on site, connected by flange or socket, without professional welding equipment, suitable for rapid construction of complex pipeline layout.

2. Excellent fire and high temperature resistance.

Class A incombustible material: it conforms to the national fire protection standard (GB8624-2012), does not burn or release toxic gas when it meets fire, and is suitable for places with high fire protection requirements (such as shopping malls, hospitals and office buildings).

High temperature resistance: it can withstand high temperature of 150-200℃ for a long time (up to 300℃ in a short time), which is better than ordinary galvanized air duct (temperature ≤250℃), and is suitable for medium temperature scenes such as kitchen smoke exhaust and ventilation of drying equipment.

3. Outstanding corrosion resistance and moisture resistance.

Chemical corrosion resistance: Magnesium cementitious materials are alkaline in nature and have certain resistance to chemicals such as acid, alkali, salt, etc., especially suitable for humid environments (such as basements and bathrooms) and slightly corrosive places (such as food processing workshops and laboratory exhaust).

Good moisture resistance: dense surface, low water absorption (≤10%), not easy to be mildewed or softened by moisture, and stable for long-term use.

4. Good sound insulation, noise reduction and heat preservation.

Sound absorption of porous structure: tiny pores in the material can absorb sound energy, reduce the noise of ventilation system (noise reduction is about 10-15dB) and reduce the interference to the environment.

Self-contained thermal insulation layer: Magnesium material has low thermal conductivity (0.2-0.3W/(MK)), which can reduce heat transfer inside and outside the pipeline, save the construction cost of thermal insulation layer when it is used in air conditioning system, and avoid the problem of condensed water.

5. Environmental protection and economic advantages

Green material: There is no heavy metal pollution in the production process, and it can be recycled after being discarded, which meets the requirements of environmental protection.

Low cost: the cost of raw materials is lower than that of stainless steel, and the comprehensive cost of installation and maintenance is low, which is suitable for small and medium-sized projects with limited budget.

Second, the advantages of stainless steel welded air duct

Stainless steel welded air duct is based on stainless steel plates (such as 304 and 316L) and is made by welding process. It is a high-end product in metal air duct, and its core advantages are as follows:

1. Super corrosion resistance and service life

Passivation film protection: Stainless steel contains chromium (≥12%), nickel and other elements, and forms a compact oxide film on the surface, which is extremely resistant to acid, alkali and salt corrosion, especially suitable for high humidity (such as coastal areas) and strong corrosive environment (such as chemical workshops and laboratories).

Ultra-long service life: The service life can reach more than 30 years in normal environment, which is 2-3 times that of galvanized air duct, and the comprehensive cost is lower after long-term use.

2. High strength and high reliability

Tough material: 304 stainless steel has tensile strength ≥520MPa, yield strength ≥205MPa, excellent impact resistance and vibration resistance, and is suitable for high-pressure air supply (such as pneumatic conveying system, wind pressure ≥3000Pa) and high-vibration scenes (such as fan outlet and industrial equipment connecting pipes).

Strong welding tightness: argon arc welding and other processes are adopted, so that the welding seam is firm and leak-free, avoiding the hidden danger of air leakage in the bite connection of galvanized air duct, and suitable for systems with high air tightness requirements (such as clean workshops and medical negative pressure wards).

3. High temperature resistance and aging resistance

Wide range of high temperature resistance: 304 stainless steel can withstand 800℃ high temperature, and 316L can withstand 1200℃ high temperature, which is suitable for industrial furnace smoke exhaust and kitchen oil fume discharge (it is not easy to deform or oxidize when exposed to high temperature oil fume for a long time).

Excellent aging resistance: stainless steel material is not easily affected by ultraviolet rays, ozone and other factors, and it is not easy to age and change color when installed outdoors or used for a long time, and its appearance and performance are stable.

4. Cleanliness and easy maintenance

Smooth surface: the stainless steel surface is smooth and flat, which is not easy to accumulate dust and breed bacteria, and meets the hygiene standards of food processing, pharmaceutical manufacturing and other industries (such as GMP workshop ventilation).

Low maintenance cost: no need for regular anti-corrosion treatment, only need to clean the surface regularly, saving maintenance manpower and cost, especially suitable for scenes that are difficult to maintain frequently (such as high-altitude pipelines and complex pipelines).

5. Beauty and high-end application adaptability

Beautiful appearance: stainless steel has high gloss, which can improve the overall aesthetics of buildings or equipment, and is suitable for places that require high visual effects (such as commercial complexes and high-end office buildings).

Adapting to high-end scenes: In the fields with harsh environmental requirements, such as aerospace, precision electronics, semiconductors, etc., stainless steel air ducts are the first choice to meet special requirements such as ultra-clean and antistatic.

Third, the core differences and selection suggestions

Weidu magnesium air duct stainless steel welded air duct

Material type Non-metallic composite metal (stainless steel)

Light weight (convenient installation) and heavy weight (professional equipment installation required)

Moderate corrosion resistance (suitable for mild corrosive environment) and extremely strong (suitable for strong corrosive and high humidity environment)

High temperature, moderate temperature (≤ 300℃) and high temperature (≤1200℃)

Medium strength and bearing capacity (suitable for low-voltage systems) and high strength (suitable for high-pressure and high-vibration systems)

Hygienic performance is generally high (the surface is porous and needs to be cleaned regularly) (the surface is smooth and easy to clean).

Low cost (less initial investment) and high cost (the initial cost is 2-3 times that of magnesium duct)

Typical scenes: ventilation of civil buildings, air conditioning system, industrial corrosive environment of temporary works, high-temperature smoke exhaust and clean workshop.

Selection suggestion:

Choose magnesium air duct:

Limited budget, the pursuit of lightweight and rapid installation.

The scene requires fire prevention, sound insulation and heat preservation (such as air conditioning in houses and shopping malls).

The ambient humidity is moderate and there is no strong corrosion (such as ordinary offices and schools).

Choose stainless steel welded air duct:

Long-term use requires high reliability and corrosion resistance (such as chemical industry and coastal projects).

High temperature, high pressure or high vibration scenes (such as industrial furnaces, pneumatic conveying).

Places with high hygiene standards or strict appearance requirements (such as food factories and high-end buildings).

Fourth, summary

Magnesia duct is light-weight, fire-proof and low-cost of nonmetal materials, which is suitable for civil buildings and conventional ventilation scenes. Stainless steel welded air duct has become the first choice for industrial fields and high-end scenes because of its high strength, corrosion resistance and high temperature resistance. In practical application, comprehensive decisions should be made according to environmental conditions, service life, budget and functional requirements, and if necessary, solutions can be customized by combining their advantages (such as stainless steel frame and magnesium plate).