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Piping Specification-details and the preparation process



Piping Specifications are usually in the form of a manual containing the below-listed points, but not limited to
            1 )      Pipe Class and Specifications.
            2)      Pipe and fittings thickness table for the different class of piping.
            3)      P & ID Abbreviations and Symbols.
            4)      List of fluids with Design conditions and Pipe Class.
            5)      List of Valves and Gaskets.
            6)      Table of Branch connections for different Pipe Classes.
            7)      Table of Bolt length.
            8)      Valve Dimensions.
            9)       Piping Scope Limit for instrumentation called as “Hook Up Diagram”.
           10)    Special Items list.

Licensor transfers the basic piping specification as part of their basic engineering package, it generally includes

a)       List of mediums that have to handle with design conditions.
b)     Dimensional and material standard of each piping element used for a particular medium
       and service conditions.
c)       P& ID Symbols and Codes.
d)      Special Piping Element Requirements.
e)      If there any Special Piping Design Requirements.

The Piping Specification will be made based on the above information from the licensor.In that process, Basic Piping Specification received from the licensor/Client will study in detail with respect to the indigenous availability of material and alternative material substitutions by the client just in case.

Detailed comments are kept ready for the time of “Freeze-In -Talks” and the client comments will mark on a copy of the document.
The document is further developed by incorporating the “Freeze-in-talk” comments, relevant standards of licensor and consultancy which include the limit of scope for instrumentation.

After including internal comments these documents will send to the Client for approval. For further proceeding, a formal approval from the client is mandatory.

This document should not be revised unless a change is required due to the addition of new fluid or non-availability of a particular item. Any such revision must be commented by Piping/ Instrument and must be approved by the client.

If the detailing consultancy itself doing the basic engineering part too, in that case, basic specifications are collected from a previously executed similar project and further proceedings as discussed above. Client’s approval is still mandatory.

This will be usually documented in A4 size sheets and used for detailed engineering and developing Technical Specifications for each element for procurement. Generation of Bill of material will be based on these Specifications, So it is very important to update BOM, in the case of any revision in the Specification.







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