Dimensions and weight of the profile pipe

Metal frames for a variety of structures are more convenient and reliable. Even if there is little inverter welding machine, assembly of any design is not a problem. In recent years, more often they use not a round, but a square or rectangular pipe. It is called profile. The dimensions of the profile pipe are very different, so you can choose a product for any purpose - for poles, and for racks, and for lintels.

What is a profile pipe 

Profile pipes are pipes whose cross-section is different from the circle. They can be oval, square and rectangular. Oval ones are rarely used. Most often, when they talk about a profile pipe, they mean either square or rectangular. It is also called profiled, professional pipe, metal / steel profile, metal profile, pipe profile. There are also names by section - square or rectangular. In general, there are a lot of names, but they are all the same material.

When they talk about the dimensions of a profile pipe, they mean its outer dimensions. Also in the nomenclature, the wall thickness is set. Thus, the greater the wall thickness, the smaller the inner section will be. Sometimes this is important and worth taking into account.

What is a professional pipe - rolled metal with a section in the form of a rectangle, square or oval

Each type of section of a profile pipe is prescribed in a separate standard. The entire assortment is described there, indicating the dimensions of the section, wall thickness and weight of a running meter of the pipe.

• square section GOST 8639-82;
• rectangular 8645-68;
• oval 8642-68.

Why is it usually used a square or rectangular pipe, and not an oval one? The profile is more resistant to some types of load than the round one. And because it is easier to make a connection with a square, whatever it may be - welded, on bolts, rivets or fasteners. And also because, due to the stiffening ribs, the professional pipe can withstand heavy loads. This is with the same radius, wall thickness and metal of the same grade.

The downside of a square or rectangular shaped pipe is that it folds when the load is exceeded. Fast and sharp. And this usually leads to the destruction of the structure. A round pipe bends for a long time and breaks very slowly. There is time to take action - to reduce the load or to strengthen the structure.

What steel are they made of

Profile pipes of any shape and section are made of carbon and alloy steel. Their brands are spelled out in GOST 13663-86, which spells out all the requirements for products. Including steel grades. It can be found from aluminum and alloys, but they are made according to DSTU, and not according to the standard. However, they are there too.

Profile pipes are made of structural steel and alloyed

Carbon steel is suitable for general use. The brand should be chosen specifically when calculating large structures (trusses). In home construction, St1sp or St3sp hardly makes a big difference. Not at all essential. Usually they take what is in the nearest warehouse and what suits the price.

Sizes of a square shaped pipe and weight of a running meter

A square pipe goes more often to racks, a supporting frame is assembled from it, and the lintels are made of rectangular. It is easier to attach materials (any) to such a frame. And also, all other things being equal, the bending strength of a square shaped pipe is higher. It is comparable to that of an I-beam. But the resistance to torsional loads in a round pipe is much higher.So this must be taken into account.

But in order to avoid problems, it is necessary to maintain the recommended dimensions of the profile pipes. As already mentioned, all sizes (assortment) are prescribed in GOSTs. Possible wall thickness is also indicated there. Small pipes - from 10 to 35 mm in diameter - have a thickness of 0.8 to 5 mm. But for pipes with a side of 10 mm and 15 mm, the walls are not thicker than 1.5 mm. Then there is a gradual increase in the minimum size. For example, 40 * 40 mm has the thinnest wall 1.4 mm, 45 * 45 mm already thinner than 3.0 mm has no wall. The same tendency is observed in the future. The larger the profile pipe, the thicker the walls.

The tables also indicate the weight of a running meter of a profile pipe of each size. It is needed not only to calculate the load on transport. Using this data, you can control the wall thickness. You can weigh a piece of pipe, calculate the weight of a running meter, and then compare with the standard. If the data is close, everything is fine. If the actual weight is much less, the wall thickness is less than the declared one. True, the table shows the weight at a steel density of 7.85 g / cm². If the density of the pipe steel is less, this will need to be taken into account.

Dimensions of rectangular shaped pipe

Rectangular shaped pipes have thicker walls. Even with the smallest section (15 * 10 mm), the wall thickness cannot be less than 1 mm. For private traders, the most popular dimensions of a profile pipe are 20 * 10 mm or 20 * 15 mm, often 25 * 10 mm or 25 * 15 mm are used. Jumpers are made of them at construction of gazebos, device of awnings, other buildings and small forms. Usually, the lintels between the support posts are made from the same pipe for fences made of corrugated board or other sheet material.

The tables show standard dimensions with wall thicknesses for each section. The weight of one running meter is also marked. At retail metal warehouses, rolled products are sold in whips - lengths that they have in stock. The minimum whip length depends on the manufacturing method. Seamless cold-worked and all electrowelded can be from 1.5 meters to 11-14 meters. This is an assortment of their unmeasured length. Whips of measured length of the same manufacturing methods are not less than 4 meters. Same minimum length - 4 meters - (both gauged and off-gauge) for seamless hot work and furnace welding.

Wholesale depots sell shaped pipes in tons. If you have a serious amount of work ahead of you, why not save some money. But in order to know how many pipe there will be in a ton, you need to divide it (ton) by the weight of one meter of pipe. Let's say you want to buy a ton of metal profile pipe 35 * 20 * 2.5 mm. One meter weighs 1.88 kg (from the table). Now we divide a ton, which is 1000 kg, by the weight of the pipe, we get 1000 / 1.88 = 531.9 m. This is almost 532 meters ... You need such a footage - great. If not, buy it at retail with whips. Just remember that in the tables the weight is indicated for steel with a density of 7.85 g / cm². If the density of the steel pipe is higher, the footage will be proportionally less.

What load can the profile pipe withstand?

The load that a profile pipe can withstand depends on its section, wall thickness and characteristics of the steel from which it was made. The manufacturing method also affects. But all these factors are taken into account only when calculating frames for buildings, bridge spans, floor trusses, etc. In less critical structures, they are usually limited to assessing the level of load that can affect the structure, and the pipe is taken with about a 20% margin of safety. This is insurance "just in case".

A few words about loads. There is a simple principle here: it is better to play it safe and take a more "hardy" pipe than to redo it all over again. Therefore, the collection of loads is a very important stage in the selection of the cross-section of the profile pipe. In private housing construction, a frame for a shed, a gazebo, a shed is usually made from a steel profile. In such cases, the mass of snow must be taken into account. It is he who usually becomes the cause of destruction.

Arches are still cooked from the profile pipe or pergolas, frames for retaining systems, assembling fences. In general, you have to be careful with arches.They are usually made for plants. When calculating, add the snow load to the mass of the trunks / branches. And in the summer, it is worth considering green mass and wind. In this combination, the loads are also not weak.