To define and secure boilers safely, some professional specialized organizations such as the American Society of Mechanical Engineers (ASME) develop standards and regulation codes.For instance, the ASME Boiler and Pressure Vessel Code is a standard providing a wide range of rules and directives to ensure compliance of the boilers and other pressure vessels with safety, security and design standards.5 Historically, boilers were a source of many serious injuries and property destruction due to poorly understood engineering principles.
Thin and brittle metal shells can rupture, while poorly welded or riveted seams could open up, leading to a violent eruption of the pressurized steam.
When water is converted to steam it expands to over 1,000 times its original volume and travels down steam pipes at over 100 kilometres per hour.Because of this, steam is a great way of moving energy and heat around a site from a central boiler house to where it is needed, but without the right boiler feed water treatment, a steam-raising plant will suffer from scale formation and corrosion. At best, this increases energy costs and can lead to poor quality steam, reduced efficiency, shorter plant life and unreliable operation. At worst, it can lead to catastrophic failure and loss of life.
The difference between pipes and tubes is simply in the way it is sized. PVC pipe for plumbing applications and galvanized steel pipe for instance, are measured in IPS (iron pipe size).
Copper tube, CPVC, PeX and other tubing is measured nominally, which is basically an average diameter.These sizing schemes allow for universal adaptation of transitional fittings.
For instance, 1/2" PeX tubing is the same size as 1/2" copper tubing.1/2" PVC on the other hand is not the same size as 1/2" tubing, and therefore requires either a threaded male or female adapter to connect them.When used in agricultural irrigation, the singular form "pipe" is often used as a plural.7 Pipe is available in rigid "joints", which come in various lengths depending on the material.Tubing, in particular copper, comes in rigid hard tempered "joints" or soft tempered (annealed) rolls.
PeX and CPVC tubing also comes in rigid "joints" or flexible rolls.The temper of the copper, that is whether it is a rigid "joint" or flexible roll, does not affect the sizing.7 The thicknesses of the water pipe and tube walls can vary. Pipe wall thickness is denoted by various schedules or for large bore polyethylene pipe in the UK by the Standard Dimension Ratio (SDR), defined as the ratio of the pipe diameter to its wall thickness. Pipe wall thickness increases with schedule, and is available in schedules 20, 40, 80, and higher in special cases. The schedule is largely determined by the operating pressure of the system, with higher pressures commanding greater thickness.Copper tubing is available in four wall thicknesses: type DWV (thinnest wall; only allowed as drain pipe per UPC), type 'M' (thin; typically only allowed as drain pipe by IPC code), type 'L' (thicker, standard duty for water lines and water service), and type 'K' (thickest, typically used underground between the main and the meter).Because piping and tubing are commodities, having a greater wall thickness implies higher initial cost.Thicker walled pipe generally implies greater durability and higher pressure tolerances.Źródło: https://en.wikipedia.org/wiki/Water_pipe#Difference_between_pipes_and_tubes.