How steel pipes have a lower safety factor?

Safety is the first and the foremost factor you consider before doing anything. May it be investment in the stock exchange or going on for a ride or doing the all new construction. If you recall the Maslow’s hierarchy of needs, you will see that after the physiological needs, the second human need is safety and security.

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This factor of safety increases to the highest when it comes to construction and buildings. Because it is not only about the strength of the building, but also the safety of human lives. The most important thing is human lives and you cannot compromise on that in any exchange. In construction and building, if you talk about steel pipes vs. ductile iron pipes, the steel pipes have a lower safety factor.

When steel pipes and Ductile Iron pipes are bid against each other owners and engineers are often hectic with the information relating to different aspects of these two materials. Many people are unknown to the actual facts, but the facts are facts. And sometimes facts are hard to come by. Whether the concern is engineering, installation, safety or operation, an objective comparison of these two materials shows they are not equal. Conservative design and ease of installation feature of ductile Iron pipes make it decidedly better than steel pipe or tubes.

Ductile Iron pipe has a standardized design procedure (ANSI/AWWA C150/A21.50), and the approach in that standard is the most conservative in the piping industry. When it comes to steel pipe, working pressure design is based on 50% of the steel yield strength, a factor of safety of 2.0. However, it is important to note that surges are allowed to increase the stress in the pipe wall to a maximum of 75% of yield. In the process, allowing the wall stress to increase to 75% of yield. This is as same as reducing the factor of safety in design to 1.33.

The factor of safety in design will vary from a maximum of 2.0 i.e. zero surges, to as little as 1.33. In either case, steel pipe or tube design allows surges to compromise the factor of safety.

Why use seamless steel pipes and tubes?

Seamless steel pipes are stronger and better than welded pipes. That is why they are preferred by industries looking for stronger alternatives. Seamless steel pipes and tubes are used in variety of areas. They are used in aircraft, missiles, anti friction bearing, machine parts and high pressure cylinders.

Seamless steel pipes have various benefits. They are stronger, more reliable, durable and work best for heavy duty activities. The outside diameter of most of these seamless tubes is 1/8 to 26 inch. One of the major benefit of seamless steel tube is the increased pressure ratings.

Welded seam is the weakest point in a welded pipe. Most leaks and pipe failures happen at the welded seam. A seamless pipe does not have a seam and that is why the tensile strength is uniform around the entire pipe. Using seamless pipe is more expensive but allows for smaller wall thickness and pipe weight, which can affect cost as well as design. Even though, seamless pipes are most expensive pipes in steel pipes, yet it is the most reliable and trusted with fewer failure points. Another benefit is that pressure calculations are easier.

Not to forget its strength under loading. When it begins transporting material, the weight of the material must also be taken into account.

What is the importance of steel pipes and tubes in heavy industries?

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Steel pipes are famous for its strength. Its strength makes it more demanding and useful in variety of areas. Talking about its applications, you must have heard about "jack and bore" construction, in which the pipe is pushed with a hydraulic ram, while an auger spins inside the pipe and carries the displaced soil back to the jacking pit, where it can be easily removed.

It is also used to transport water. And not to forget its ability to be recycled. Steel is protected in two ways to prevent corrosion and increase strength, by galvanization or by making it into an alloy. There are various types of steel. Galvanized steel is only coated, whereas alloys are combination of steel and carbon. Super deluxe is a super steel alloy, made by modifying metal alloys. Although these are superior in use, but the cost is high.

Another type is stainless steel. They are made from steel-chromium alloy. It is the cheapest of all. Carbon steel is another type which is extremely malleable and can be used to form small precision components. Organizations try to be cost effective and to do this, the cost against safety, effectiveness and longevity has to be balanced.

Why use steel pipe and tube fittings?

Steel pipe or tube is a building material made from an alloy of iron and carbon. Steel pipes are also called steel tubes in some part of the world. There are variety of steel products. It is used in variety of manufacturing and industrial applications. The reason for its variety of uses is that, it can be easily grooved, cut and threaded in size, on-site.

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However, steel pipes are widely used for construction purposes, they are also very commonly used in transporting liquid and gases from one location to another. This material is also used as a structural component for scaffolding and framing systems. The most famous project for transporting petroleum products is the Trans-Alaska pipeline. These transmission pipes have a diameter of 48" and larger. And it is 800 miles long.

It is one example from many. Steel pipe is hollow and has a relatively low strength to weight ratio, hence, steel pipe engineers can design it for many uses. It can be used on a large scale as well as small scale. A real life example for large scale would be the support pole of massive highway billboards and small scale example would be a bicycle frame tube. Steel pipe's strength and rigidity allows it to be pushed under roadways and railroads without traffic disruption.

Not to forget its ability to be recycled. Steel pipes are recyclable and have high reclamation rate. Recycling is not only important for the economic purpose, but environmental factors also force us to use things which are recyclable easily.