Skip to main content

Re: [MW:36030] API 650 - Tolerances for Bottom Plate Distortion

By Materials & Welding

The observed distortion (~45 mm) exceeds acceptable industry practice and may lead to uneven stress distribution and 

loss of bearing. Typical industrial (not code mandated but widely accepted) practice is within 10 to 15 mm. 

As API 650 requires proper seating of bottom plates you can cut, refit, reweld to ensure  restoration of structural integrity 

and compliance with code requirements. 

Reduce the heat input by adopting sequence or skip welding methods and use strong back ups. Also check the foundation 

level before laying the plates. Use Laser level inplace of a straight edge. Trust it is clear.

Sridhar.

-----------------------------------------------------------------------------------------------------------------------------------------------------------------


On Sat, 18 Apr 2026 at 12:38, Raminshah Muhammed <ramin.pcsb@gmail.com> wrote:
Dear Experts,

Is there any tolerances for bottom plate distortions, as I checked only foundation tolerances are specified in API 650. As we have 45mm distortion observed in one of the plates, how can we control it, as per code.

--
https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---
You received this message because you are subscribed to the Google Groups "Materials & Welding" group.
To unsubscribe from this group and stop receiving emails from it, send an email to materials-welding+unsubscribe@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/materials-welding/175e3d47-c294-4f11-a1f6-7ea014b68457n%40googlegroups.com.

--
https://materials-welding.blogspot.com/
https://www.linkedin.com/groups/122787
---
You received this message because you are subscribed to the Google Groups "Materials & Welding" group.
To unsubscribe from this group and stop receiving emails from it, send an email to materials-welding+unsubscribe@googlegroups.com.
To view this discussion visit https://groups.google.com/d/msgid/materials-welding/CAHo%3DYijy6ZDrMUiH-jFqjhowVBZ_9HHN7JTzWkQsP4i3Je-6Lg%40mail.gmail.com.

Comments

Post a Comment

Popular posts from this blog

Re: [MW:34105] SA266 GR4N 4 Cycle SPWHT

By Materials & Welding
Hi,  You are correct, Minimum refers to the one cycle for which this part will expose until final work shop PWHT. hence mill test certificate shall include this.  Max. SPWHT, refers to additional cycles of heat treatment that are reserved for future repairs during equipment lifetime.  Again, these simulated no. Of cycles shall be specified in MTC.  The idea is we need to make sure that steel mechanical properties are not compromised upon exposure to multiple repairs (i e 4 cycles in your case).  One could say, if steel is subjected to 4 cycles and is ok, then it should by defacto be good for one cycle, yet, this is wrong assumption cause mechanical problems and microstructure of materials varies accordingly based on no. Of cycles for which material will expose. This is apparent in alloy steel and especially for impact test values as an example.  In your case, this forged CS with properties before PWHT can be understood to be " as forged" condition (i.e. Wit...
Post a Comment
Read more

Materails FAQs

By Materials & Welding
Q: What are equivalents for standard Q 235 B (and Q 235 A) for U-channels? (asked by: boris.vielhaber@vait.com) A: DIN Nr. = 2393 T.2, 2394 T.2, EN 10025 W. Nr. DIN 17007 = 1.0038 Design DIN 17006 = RSt 37-2, S235JRG2 (Fe 360 B) Q: What is St DIN 2391 BK material? (asked by: dmcandrews@automaticstamp.com) A: Precision steel tubes, cold-finished/hard. Q: What is C.D.W. Boiler Tube? (asked by: montydude123@yahoo.com) A: Cold Drawn Welded Boiler Tube. Q: WHAT IS W.Nr. 1.4301? PLS TELL US IN EASY LANGUAGUE (asked...
21 comments
Read more

Heat tint (temper) colours on stainless steel surfaces heated in air // Heat tint

By Materials & Welding
Introduction The colour formed when stainless steel is heated, either in a furnace application or in the heat affected zone of welds, is dependent on several factors that are related to the oxidation resistance of the steel. The heat tint or temper colour formed is caused by the progressive thickening of the surface oxide layer and so, as temperature is increased, the colours change.   Oxidation resistance of stainless steels However, there are several factors that affect the degree of colour change and so there is no a single table of colour and temperature that represents all cases. The colours formed can only be used as an indication of the temperature to which the steel has been heated. Factors affecting the heat tint colours formed Steel composition The chromium content is the most important single factor affecting oxidation resistance. The higher the chromium, the more heat resistant the steel and so the development of the heat tint colou...
Post a Comment
Read more