Process Piping Materials – Module 2 – M06-036

•Applications

Some of the common service applications of Zirconium Piping include:

−Acetic Acid

−Citric Acid

−Formic Acid

−Hydrochloric Acid

−Lactic Acid

−Nitric Acid

−Phosphoric Acid

−Sulfuric Acid

•Standards

−ASTM B653 PZ2

2.13.Chrome - Moly

•Characteristics

−Stronger and harder than regular steel.

−Nt as resistant to corrosion as stainless steel.

−Best for transportation of pressurized gases.

•Applications

−Power plants, fossil and nuclear.

•Standards

−ASTM A199: Covers several grades of chromium-molybdenum and chromium-molybdenum-silicon seamless cold drawn intermediate alloy steel tubes for heat exchangers, condensers, and similar heat transfer apparatus. Includes sizes 1/8 in. to 3 in. inclusive in O.D.

2.14.Brass

•Characteristics

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Process Piping Materials – Module 2 – M06-036

−Brass is a family of alloys of copper and zinc with copper content from 90 to 60% with balance zinc. Yellow brass has 66% copper and 34% zinc.

−Some brasses have small amounts of other elements such as lead, tin, antimony, arsenic or phosphorus.

−It finds various applications from potable water supply to heat exchanger piping owing to its excellent resistance to corrosion from water containing impurities.

−It shows good corrosion resistance in most environments but not recommended for acetic acid, acetylene, ammonia and salt.

−Maximum temperature limit is in the order of 500°F/260°C.

−Aluminium and silicon bronzes are more resistant to salt water than simple brass and are widely used as condenser tubing when salt water is the cooling medium.

2.15.Aluminium

•Characteristics

−Aluminium has good resistance to corrosion from sulphur compounds and to atmospheric oxidation.

−Extremely light weight and melts at 1220°F/660°C.

−Corrosion resistance similar to SS, but it is very low strength material with a Brinell hardness of approximately 35.

−Rarely used in industrial piping except in the certain typical service of urea. However, aluminium coated steel is used in certain equipment to save it from sulfur compounds and oxidation at high temperatures.

−Its specific corrosion resistance characteristics make this non-toxic and it finds applications in drug, food and beverage industries.

−Has good thermal and electrical conductivity and machining properties.

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Process Piping Materials – Module 2 – M06-036

2.16.Copper

Copper has long been used for all types of domestic water services and distribution because it:

−is durable

−has good corrosion resistance

−is malleable and easy to bend

−is self-supporting

−has good flow characteristics

−requires few fittings

−can be recycled

Copper may be annealed (i.e. heated, then cooled slowly) which improves its properties, for example making it less brittle and stronger.

Although copper in general has good corrosion resistance, this depends on the environment. Acidic conditions, either from the soil (if buried) or from the water, can cause corrosion, so local pH levels should be checked before using copper pipes.

Common wall-thicknesses of copper tubing are "Type K", "Type L" and "Type M"

•Type K

−Type K has the thickest wall section of the three types of pressure rated tubing and is commonly used for deep underground burial such as under sidewalks and streets, with a suitable corrosion protection coating or continuous polyethylene sleeve as required by code.

•Type L

−Type L has a thinner pipe wall section, and is used in residential and commercial water supply and pressure applications.

•Type M

−Type M has the thinnest wall section, and is generally suitable for condensate and other drains, but sometimes illegal for pressure applications, depending on local codes.

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Process Piping Materials – Module 2 – M06-036

Types K and L are generally available in both hard drawn "sticks" and in rolls of soft annealed tubing, whereas type M is usually only available in hard drawn "sticks".

2.17.Boiler and Heater Tubes

Summarizing:

The table below provides the summary of frequently used ASTM Grades.

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Process Piping Materials – Module 2 – M06-036

Frequently used ASTM Grades

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