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[MW:3726] Bolts/Nuts Material

By Materials & Welding
HI,
 
I want to clarify a deviation request from Valve vendor,
As per the client specs,
 
For Bolting for Bonnet, Packing-box etc
All carbon steel or low alloy steel bolting shall be zinc plated(elctro-deposited), bichromated.
 
but vendor is proposing
 

Our proposal for A216 WCC Body (Non-Sour) as follows;

Body Studs & Nuts (21000 Series): A193 Gr.B7 / A194 Gr.2H zincplated

(without chromated)

Body Studs & Nuts (35002 Series): A193 Gr.B8 CL.1 / A194 Gr.8

Gland Studs & Nuts : A193 Gr.B8 CL.1 / A194 Gr.8
 
so my dout is in humid areas like Japan we need the bolts to be
Zincplated/bichromated to prevent white rust and in hot areas like
Qatar its not required. 
Please confirm my understanding,
(As the specs were basically developed by JGC they specified as
zinc plated/bichromated)
 
 
Ohm-Srinivas
Sr. Piping Engg.

ohm guru namasivaya

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