Heat Exchanger Inspection Checklist

[james10]

Hi Guys,

I need to visually inspect a tube & shell heat exchanger including dimensional verification , does anyone know where I can get a checklist which would be suitable for the job

 

[pipewelder1999]

Often times the project specifications will have an inspection and test plan that may list some attributes that are required by contract. In my experience with these types of inspections here are SOME of the attributes I have inspected. Requirements vary with the customers. TEMA may have some information of use.

Tubesheet hole diameters and groove Dimensions
Tube OD and Wall
MTR's
Orientation of inlet, outlet, and baffles
Verification of baffle tie rods being properly secured
Nozzle material, location, square, plumb, two-hole
Internal prior to bundle insertion
Shell Dimensions
Head/Channel Dimensions
Impingement plate installation
Welder Qualifications
Tube Rolling Procedure
% Reduction in Wall
In-Process Welding
Final Welding
Saddle/Support location and orientation
Gasket Material
Head/Bonnet Bolting Procedure
Final condition of gasket seating surfaces prior to shipment
Observation of Soap Bubble/Helium Leak/Hydrostatic testing where applicable.

Hope this helps a little



Gerald Austin
Iuka, Mississippi

http://www.weldinginspectionsvcs.com

 

[bmoorthy]

James10

The inspection approach is different for equipments after it is put to use as compared to the equipments which is being fabricated. For inservice inspection you may have to check with NBIC, for fabrication inspection refer to the following from ASME, TEMA, API 660, API 572, these would help you in preparing your own check list.

How to go about where to start?

HSW has released a figure, clause by clause (Only clause number) affecting each location of vessel. Have a copy of it in your dairy. If you do not have it already, go to any library and take a copy of it from Chemical Engineering
Hand Book (Perry).

Prepare a copy of UW 51 and 52 (Radiography acceptance criteria) with appendix 4, other NDT appendis Skim through.

For shape check refer to UG 80.

For Material Impact requirement UG 84 and UCS 66

PWHT cycle UCS 56. Heat treatment after forming UCS 78/79.

Specifics related to Dimension of Heat exchanger TEMA. Here you would get tolerances on Girth flange dia, Tube sheet Dia and Hole Dia. Also TEMA provides Leak testing (Guideline as to when all this is possible) and hydro testing (Holding time), you may also get some guidelines as to what types of discontinuities can be tolerated on gasketseating surface, also Go through recommended practices. Further guidelines related to refinery are given in API 660.

For material requirements refer to ASME sec 2.

WPS PQR WPQ refer to ASME sec IX.

 

[quadswift]

You do not say whether this is new or in service.

If it is new then the supplier should have (and have supplied you with as part of the PO documentation requirements?)his own ITP/QCP for all the verification aspects and you can inspect against that, the drawings, data and specifications etc.

If it is used / in service, then in the manufacturing record books that came with the exchanger there should be a copy of the original ITP/QCP to refer to.
The manufacturing verification would have been done at original build.You then need to inspect for deterioration / corrosion from the original status, details of which should be found in the original drawings / data / certification.
This may include taking wall thickness checks in critical areas. You need to keep records of these, including the exact locations so that you can repeat the excercise in future and determine any / the rate of corrosion.
You should also have (by law - when you place such an item into service)an in-service inspection program which should determine the inspection intervals and the inspections to be undertaken.
Regards,
quadswift

 

[SangoBay]

Inservice inspection should cover items such as tube to tubesheet welds/joints including ndt if they are welded. Dimensional checks should be staight forward. Tube inspection can be done using eddy currents down the bore of the tube to determine any wall thinning or fretting. Ultrasonics could also be used down the bore. If you have any nozzles on your shell then a boroscope in the localised area could be used. New boroscopes have excellant resolution and good lighting systems but they cost toooo much, though you could use one of these for the tube bore inspection.
Not much here but I hope it helps.
Roy.