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  Selecting pipe and piping materials
Posted by: suc9cess - October 21, 2021, 11:30:06 PM - No Replies

Steel Pipes
Steel pipes are the most commonly used pipes in water supply systems. They are also used in pipelines for natural gas, and sewerage systems. Although comparatively expensive to other pipes, they hold the advantage of being able to withstand high pressures and are available in more convenient lengths, and can also be welded easily, thereby resulting in lower installation and transportation costs. These types of pipes are highly efficient and can be used in small diameters as needed and are 100% recyclable compared to other materials. The pipes can further be melted down and turned into other usable material in industry. Furthermore, the high strength of these pipes and resistance to damage caused by human errors, tree roots, and extreme weather conditions make these pipes the ideal choice for most water and sewerage supply systems.

The disadvantages of steel pipes include thermal conductivity, which is very poor as there is a difference in heat transfer. These types of pipes are usually bonded with aluminum or copper alloy to increase thermal conductivity and improve heat transfer. Cost is another issue, as these pipes are expensive and this is guided by the misconception of being a one-time purchase. However, steel pipes are difficult to fabricate and lack the malleable qualities that other materials have, therefore repairs and replacements of steel pipes are extra difficult.

Basic material properties

Steel is strong, rigid, and has a low coefficient of thermal expansion. It is also heavy (multiple workers may be needed to transport it) and is subject to corrosion. Sometimes it is called carbon steel or black special steel to differentiate from stainless and galvanized steel. All steel, by definition, contains carbon.

Steel often is used for closed hydronic systems because it is inexpensive, especially when compared with other materials in systems with high pressures, and corrosion is relatively easily controlled in these systems. It also is a good choice for steam and steam-condensate systems because it handles high temperatures and pressures well, and corrosion is normally not an issue in steam pipes. However, corrosion is an issue in steam-condensate pipes, and many engineers specify schedule 80 steel pipe simply because it takes about twice as long to rust through as schedule 40 pipe.

If amines (commonly cyclohexylamine, morpholine, or diethylethanolamine (DEAE) are fed properly to neutralize condensate pipe pH, condensate pipes can last the life of the building. Some building owners do not want these chemicals in steam that may be used for humidification because of health concerns; however, not using these amines might require a change to stainless steel(SS) piping or adding a separate “clean steam” system for humidification and for sterilization of medical instruments.

Rigidity is important because it determines the distance between hangers. Steel pipe is manufactured in 21-ft lengths, and the hangers can be spaced that widely for large-diameter pipe. More flexible materials, however, may require hangers on as close as 4-ft centers or even continuously. Consult ANSI/MSS SP-58: Pipe Hangers and Supports – Materials, Design, Manufacture, Selection, Application, and Installation for details about hangers and hanger spacing.

A low coefficient of thermal expansion minimizes the need for expansion loops and expansion joints. However, the high rigidity of steel means that although it expands less, it exerts very high forces on anchors.

Galvanized steel pipe is steel pipe that is dipped into a pool of zinc (see Figure 1). Galvanizing has two methods of corrosion reduction:

It coats the surface like paint, and under most circumstances it forms a very adherent oxide layer like aluminum and SS.
It provides a sacrificial anode (zinc) to receive corrosion instead of the steel corroding.
Galvanized steel pipe has all the advantages of steel pipe, and is used in insulated and coated piping, plus improved corrosion resistance in most environments, although at a slightly higher cost. Galvanizing works almost perfectly in applications where it is wetted and dried periodically (e.g., road signs and guard rails). It can fail in environments with high sodium (e.g., softened water that started out very hard) because the sodium makes the adherent oxide film detach and react more like steel pipe where the oxide flakes off. If galvanized pipe is being welded, the welder needs to be careful to grind down to the raw steel. Repairing galvanizing on the inside of the pipe is difficult or impossible. If the interior needs a continuous galvanized layer, consider mechanical couplings. (More information is available via the American Galvanizers Association.)

Copper pipe often is used in both hydronic and domestic applications, especially for 2-in. and smaller pipe sizes. However, some contractors propose replacing galvanized steel domestic-water pipe with copper up to 6-in. in size, especially in the Midwest. Copper is an expensive material but has the advantage of weighing less than steel and may require fewer employees to install, depending on weight and union restrictions. Also, copper is generally more noble and corrosion-resistant than steel or galvanized steel pipe fittings.

Stainless steel is widely considered to be resistant to all corrosion. This is true in many circumstances, but not all. Anaerobic and chloride corrosion can affect SS. The most common alloy is 304 SS, which adds 18% chromium and 8% nickel to steel. 304L has reduced carbon content to minimize the tendency for SS to corrode at welds. SS with the L designation is recommended for all SS that will be welded and might have corrosion issues, like fume exhaust and some pipe systems. 316 and 316L add molybdenum to reduce susceptibility to chlorides.

In the past decade, we have seen thinner SS being proposed as an alternative to galvanized seamless steel tube and pipe and larger-diameter copper pipe, primarily for domestic potable-water piping. There is one potential problem with this if done incorrectly (see, “Mixing materials may equal trouble”).

SS requires some oxygen to build an adhering oxide layer, like aluminum car wheels. This is normally not a problem in hydronic heating/cooling systems or domestic-water systems, but a large chilled-water-storage system could have oxygen levels become low enough to have issues with microbially influenced corrosion (known as MIC).

There are many grades of SS. In general, 300 series alloys are the most corrosion-resistant and are nonmagnetic. 400 series are harder, more resistant to abrasion, withstand higher temperatures, and are magnetic. 200 series alloys are used in sinks and applications where less corrosion resistance is acceptable.

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  Westport City Strays: a Stray Dogs RP
Posted by: WestportStaff - September 05, 2020, 06:08:34 PM - No Replies

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  The Hereafter — Multispecies Animal RP
Posted by: The Hereafter - July 14, 2020, 06:51:12 PM - No Replies

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Posted by: Rhino - July 05, 2020, 03:11:34 AM - No Replies

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Home Page ; Discord

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  THE FALL OF MAN: Fantasy Animal RPG l No App
Posted by: Cman710 - June 03, 2020, 04:38:52 AM - No Replies

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It’s been seven hundred years since the world was reduced practically to ash - putting humankind on the brink of extinction. From the ashes, the animals have risen to power and claimed the world as theres - building walled cities and keeping what’s left of mankind as pets. But quietly, from the “great unknown” beyond the capital city word of an uprising whispers through the land. Is this the beginning of the downfall of the animal kingdom? Only you can decide!

THE FALL OF MAN is a unique no application required animal and human RPG unlike any other. Take on the role of a multitude of animal species or a human pet as their hard fought for world faces its “darkest hour”.

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  UPROAR | a unique warriors roleplay
Posted by: Devi - May 18, 2020, 12:24:47 PM - No Replies

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  Elvera [Canine RP]
Posted by: Elvera - May 04, 2020, 08:13:10 PM - No Replies

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Rules | Species | Advertise[url=][/url]

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  Azeil's Acceptance
Posted by: Lish - April 24, 2020, 12:54:14 PM - Replies (2)

Azeil was aware that she was in Nardir territory. She had her head submissively low and was not sneaking or prowling around. She was looking for someone, anyone who could talk to her and let her in the pack. Her skin hugged her bones so hard you could see her ribs through her thick striped fur and it was a little painful to look at. She was looking around, looking for anyone. She wanted to join this pack really badly.

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  Cimoron Island [fantasy horse rpg]
Posted by: DOT - April 18, 2020, 08:03:22 PM - No Replies

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  Abstraction // 16+. Open World Animal RPG
Posted by: Bom Bom - April 08, 2020, 03:38:02 PM - No Replies


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[url=] Home | Guidebook | Link Back
Our planet, Okaria was created by Rhoszelys, a being who now exists only in tales passed down through centuries. To protect this planet, Rhoszelys had created guardians of powerful energies to watch over and guide okaria's life. These guardians soon became revered to as deities.

One day, Rhoszelys mysteriously disappeared leaving the deities in distress. Upon her disappearance, a new entity was created. Something not quite alive, but not quite dead. Something with energies that made even the deities weary. Whatever this thing touched would be devoured by it, and broken down into but figments of what it once was. this swirling mass was decorated with chaotic colors and patterns, and no one was sure what to make of it.

This entity was soon dubbed the abstraction. Whatever touched it would be devoured and transformed into an abstract thought, stuck in a limbo between reality and imagination. Forever trapped in a state where existence lay just out of reach.

As the abstraction grows, the whole world glitches. Continents would shift, people would find themselves somewhere completely different than they were a moment ago, and some would even find themselves in other universes. Likewise, individuals from other universes would mysteriously appear in okaria.

Whenever the abstraction grew, this glitch would occur, sometimes it was more severe than other times. This phenomenon became known as rifts, and though they were few and far between, it was still a huge threat to the world. Fear began to circulate that the abstraction could devour the entire world, as it had already done to several small islands.

What happens to us when our world turns to shards? Is there anything we can do to stop it?

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