UNDERSTANDING PIPE SCH CHART ANSI B 36.10 & ANSI B 36.19

It is very mandatory for piping engineer to understand the SCH. Chart ANSI B 36.10  & ANSI B 36.19

Brief Description as follows:

1)    Left 1^St column Nominal pipe size ,Practically we are saying as NB Means Nominal Bore Size .The word Nominal is itself described that what is denoted it is somewhat different

2)    If we take 1” pipe it’s OD is 1.315” i.e. upto 12” including 12” the OD of pipe is higher than whatever it is denoted

3)    Such as ½” pipe 0.840” OD, 2” = 2.375” OD etc.

4)    It is more important that Sch. Chart to understand that OD= Outer diameter is fixed

5)    Secondly it has thickness , thickness is increases with Sch. No. which directly depends on the internal pressure of conveying fluid in the pipe

6)    Thus we understand that pipe OD is fixed and it is varying with respect of sch. No.

Sch No. increase thickness is increases & ID is decreases

In chart it is given that 10 , 10S what is difference of it.

“ S” is stand for the Stainless steel , also we observed that it is repeated in 10S,40S,80S only that means that stainless stell ( ASTM SA 312 TP 304 or 316 etc) that pipe is coming in only that SCH. NO.

XS,XXS that pipe is denoted as extra strong pipe & schedule /Double Extra Strong Pipe

It is seen that in the chart there is blank spaces or “ _”  ,Where it is coming it means that NB size of that thickness is note manufacturing Such as 1” Sch 20 Pipe is not coming etc.

Above 12”, 14” pipe OD is same 14” has 14” OD

Direct formula for calculating the WT of Pipe

Wt. of Pipe ( Kg) = (OD – Thk.) x Thk x length x 0.025

OD in MM

Thk is in MM

Length in Meter