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Piping Codes & Standards-A Brief Summary to ASME B 31.3




Piping Engineer always strives for a Good Design and a Good design should consider aspects such as Optimized design, cost-effectiveness, reliability, safety etc
Standardization can reduce confusion among various stages in system, components, and procedures. These optimized standard practices in written form are available and are named as Codes and Standards.

CODES

A group of general rules of systematic procedures for design, fabrication, installation, and inspection prepared in such a manner that it can be adopted legal jurisdiction and made into law.

STANDARD

Documents prepared by a professional group or committee who are believed to be good and proper engineering practice and which contain mandatory requirements. The users responsible for the correct application of the same, compliance with a standard doesn’t give immunity from legal obligation.

In order to optimize the piping in process and refinery field, we use the code establish by ASME named ASME B 31.3

Following chapters are covered under B 31.3

1)Chapter I- Scope and Definition
2Chapter II -Design
3)Chapter III- Materials
4Chapterr IV -Component Requirements
5)Chapter V -Fabrication, assembly, and erection
6)Chapter VI- Inspection, examination, and testing
7)Chapter VII- Non-Metallic Piping
8) Chapter VIII- Piping for Category M Fluids
9) Chapter IX -High-Pressure Piping

For piping to conform to ASME B 31.3, the requirements of chapters I thru VIII are applicable. For Category M fluid service, piping to comply with the chapter I thru VII and the additional requirements of Chapter VIII.

For category D fluid service, requirements of Chapter I through VII are applicable. However concessional provisions made in these chapters for category D fluid service may be used.

As per code owner is responsible for identifying those fluid services which are in category D and M as defined under para 2.0.

Some requirements pertaining to Category M fluid piping are

1)Fitting conforming to MSS-SP-43 shall not be used.
2)Pipes conforming to ASTM A314 made from ASTM A 285 plate and pipes conforming to ASTM       A139 shall not be used.
3)A mitre bend that makes a change greater than 22.5 o shall not be used.
4)Single welded Slip on Flanges shall not be used
5)Valves having threaded bonnet joints shall not be used.
6)Carbon Steel pipes and fittings without impact testing shall not be used at temperature below -200C

   ...... etc etc

Some requirements pertaining to  D Fluid service

1) Following CS pipes May be used only for Category D Fluid Service
   A) API -5L Furnace Butt Weld
   B) ASTM A 53, Type F
   C ) ASTM A 120
   D ) ASTM A 134 made from other than ASTM A 285
   E) ASTM A 211

2) A mitre bend which makes a change in direction at a single joint greater than 45 may be used only       for category D Fluids

3) A Bolted Bonnet Valve Whose Bonnet is secured to the body by less than four bolts or by a U-bolt
4) Caulked Joints Such as bell type joints and soldered joints may be used only for category D fluid services.  

we will have a detailed and Design specific Studies from 31.3 in the Coming Blogs 

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