Supply Pipeline Equipment External Insulation Construction Iron Sheet Aluminum Sheet Insulation Construction Price

Supply pipeline equipment external insulation construction iron sheet aluminum sheet insulation construction price

After the pipeline equipment is externally insulated, the outer layer is covered with iron sheet or aluminum sheet not for aesthetic reasons. This metal protective layer plays a direct decisive role in the normal service life of the insulation. Once it is damaged and water enters it, the insulation material will lose its effectiveness. The cost of repairs and replacements is three to five times the original installation cost. There are many factories that, in order to save just a few dollars per square meter, end up having to rework after two years.

How to choose between iron sheet and aluminum sheet?

If we consider the price of iron sheet and aluminum sheet insulation construction for supplying pipe equipment external insulation construction in terms of material cost, galvanized iron sheet is cheaper than aluminum sheet by 8 to 12 yuan per square meter. However, iron sheets will rust in about two years if they are in a humid environment. Especially in environments such as chemical workshops and coastal factories, rust will continue to spread along the seams. Although aluminum skin is more expensive, it has strong corrosion resistance. If used outdoors or in the presence of acid and alkali gases, its service life can reach more than 10 years.

Let’s first look at the difficulty of construction. The hardness of the iron sheet is relatively high, so it will be more difficult to cut it, and it will also be more difficult to fold the edges. In this case, the labor cost per square meter will be about 5 yuan higher than that of the aluminum sheet. Looking at the aluminum skin again, it is soft in texture, so it is easier to process. It is easier to make a fitting shape at the elbow position, and it is also easier to make a fitting shape at the tee position. The outer protective aluminum skin of the ventilation duct insulation layer is riveted and welded . However, the thickness of the aluminum skin should be controlled at more than 0.5 mm. If it is too thin, pits will easily appear.

From a practical case, there is a steam pipe in a chemical plant in Shandong, which was protected by iron sheets in 2019. However, by 2023, the steam pipes had been rusted through in large areas; looking at the food factory in Jiangsu, aluminum sheets were also used in such an environment, and they are still intact after 7 years; if the budget allows, aluminum sheets are indeed a more worry-free option.

Main factors affecting construction prices

The diameter and shape of the pipe will first affect the price. The price per square meter of the straight pipe section is the smallest because it can be formed directly with the help of a plate bending machine. However, special-shaped parts such as elbows, reducers, and valves must be laid out and cut on site. The time spent manually is three times that of straight pipes, so the unit price is naturally much higher. For small pipes with a diameter less than 100 mm, their operating space is limited, and the price is higher than that of large-diameter pipes.

Important variables include the construction height, the work that can be done on the ground or scaffolding below two meters, and the labor cost per square meter is about 35 to 45 yuan. However, once it exceeds 5 meters, it is necessary to build a full hall or use a lift truck, and the price will rise to 60 to 80 yuan. A heating company carried out high-altitude pipeline work in December 2025, and the safety measure fee alone accounted for 18% of the total price.

The differences between regions cannot be ignored. From the perspective of the Yangtze River Delta and the Pearl River Delta, the labor cost is about 30% higher than that in the central and western regions. Take the market situation in March 2026 as an example. In the Shanghai area, aluminum cladding with a size of 0.5 mm, if the material is assembled, ranges from 120 to 150 yuan per square meter. However, in Henan, the same specification only costs 85 to 110 yuan.

Preparatory work that must be done before construction

Before the iron sheet is officially wrapped, it must be checked whether the insulation cotton appears loose or has gaps. In 2025, in a project in Beijing, the outer protective aluminum skin of the ventilation duct insulation layer was riveted and welded . It was precisely because this inspection was not done that one of the insulation cotton fell off but was never discovered. After the iron sheet was wrapped, the cold bridge showed condensation. Only three months later, the pipe bracket was rusted and broken. When construction workers check the surface flatness of the insulation layer, they need to use a 2-meter ruler. Those locations where the error exceeds 5 mm must be trimmed.

The key point is also the material acceptance. The thickness of the iron sheet or aluminum sheet entering the site needs to be measured with a micrometer. There are often products on the market with negative tolerances. The nominal value is 0.5 mm, but the actual thickness is only 0.43 mm. It is also necessary to check whether there is oil stain or oxide layer on the plate, otherwise it will easily slip off after riveting. In a project carried out by an installation company in Tianjin in 2024, it was precisely because of the use of oil-stained aluminum that all the edges of the rivet holes were torn after half a year.

First of all, the construction plan must be technically explained, especially where the wall and floor are penetrated, and the waterproof flanging method must be determined in advance. Then, the experienced team will make sample sections in advance and wait for the owner's confirmation before expanding to a large area. This can avoid the waste of materials caused by rework.

Four core points for standardizing construction

The direction of overlapping must be along the direction of the water flow and the direction of the wind. The iron joints of outdoor pipes must be laid from high to low like fish scales, so that rainwater will not flow back. There was a heavy rain in Dalian in 2023. Because the overlapping direction of a power plant was reversed, water poured into the insulation layer from the joints, causing frost to appear on the outer wall of the entire pipeline. The width of the overlap in the horizontal direction cannot be less than 50 mm, and the width in the longitudinal direction cannot be less than 30 mm.

There are particularities about the spacing and arrangement of rivets. The rivet spacing in the straight pipe section is controlled in the range of 150 to 200 mm, while the elbow needs to be denser to 100 mm. Then the rivets should be driven at the trough position rather than the wave. Peak position, so that the nail head will not protrude and will not be easily knocked loose. In addition, the dosage per square meter is about 25 to 30. When choosing aluminum rivets, it must be matched with aluminum skin. When choosing iron rivets, it must be matched with iron sheet. They cannot be mixed.

Use experience to control the roundness. Touch the wrapped pipe with your hands. There should be no obvious edges, corners or depressions. The standard for judging whether it is qualified is to stand and observe it from a distance of 3 meters. The cylindrical outline of the pipe should appear smooth. If there is a local bulge, it means that the insulation quilt inside has been pressed too hard or there are hard lumps. In this case, it needs to be disassembled and adjusted.

Expansion joints must not be forgotten. Long straight pipe sections need to reserve an expansion joint every 6 to 8 meters, and the expansion joints must be filled with flexible sealant. However, some construction teams do not reserve expansion joints in order to save trouble. As a result, when the pipes are heated and expand in the summer, the iron sheets will arch and deform, and the rivet holes will be stretched into long holes, thus losing their fixing effect.

Pay attention to three places when checking and accepting

At the beginning, you need to check the tightness of the joints. Hold the flashlight close to the pipe wall and shine it. If you can see light leakage from the joints, it means that the gaps are too big and need to be filled with sealant. In addition, you should also check whether the rivets are missed or crooked. Every time a nail is missing, that location becomes a hidden danger of water intrusion.

The first task is to deal with special-shaped parts, paying special attention to the covering of tees, elbows and flange covers. To check whether it is compliant, high-quality craftsmanship can achieve that all folded edges are relatively smooth, and there are no adverse conditions such as warping or cracking. For valve insulation, it needs to be made into a removable box, and each bolt should be able to be easily twisted. During the acceptance inspection of a certain project in Ningbo in 2025, it was found that 9 of the 32 valve boxes could not be opened. Due to this situation, all of them were reworked.

The third aspect depends on identification and finished product protection. The name of the pipeline medium and the flow direction arrow need to be clearly marked. They cannot be written directly on the iron sheet, but should be sprayed with a special template or affixed with a weather-resistant label. After the construction is completed, the iron sheet debris must be cleaned up in time, because these things are very sharp and can easily cut the hands of subsequent workers.

The latest price range reference in 2026

There is a comprehensive unit price, which is the unit price formed by contracting work and materials. Among them, the price per square meter of a 0.4 mm galvanized iron straight pipe section is in the range of 70 yuan to 70 yuan and up to 25 yuan, and the price of special-shaped parts such as elbows is in the range of 120 yuan to 120 yuan and up to 40 yuan. The price per square meter of a 0.5 mm thick aluminum skinned straight pipe section ranges from 100 yuan to 100 yuan, with a range of 35 yuan, and the price of special-shaped parts ranges from 160 yuan to 160 yuan, with a range of 60 yuan. When the material is stainless steel plate, the price is higher. Material with a thickness of 0.5 mm costs 180 yuan to 180 yuan and then 80 yuan per square meter. It is usually used in fields such as food and medicine.

Including only labor but not materials, the price per square meter of iron sheet construction is between 25 yuan and 40 yuan, and the price of aluminum sheet construction is 30 yuan and 50 yuan per square meter. For special-shaped parts, the price will increase by 50% to 100%. It should be noted that these prices are reference market prices in East China in the first quarter of 2026. The specific prices shall be based on the quotations after on-site surveys.

An insulation engineering company had an actual quotation case in February 2026. A steam pipe is 200 meters long, 325 mm in diameter, including 12 elbows and 4 valves. The ventilation pipe insulation layer is riveted and welded with aluminum skin for outer protection . It uses 0.5 mm aluminum skin. The total price is 28,500 yuan, equivalent to 118 yuan per square meter. This price covers 3% of losses and transportation costs.

When choosing a construction team, do you focus more on low unit price or fine workmanship? Would you be willing to pay 15% more to purchase a five-year warranty service? You are welcome to share your thoughts and ideas in the comment area, and don’t forget to like and forward it to your colleagues in need.