Butt-weld joint preparation 1

[ElCidCampeador]

According to ASME VIII Div.I, are there particular restrinction of type of butt-weld joint preparation (X or Y, ando also angle 30° or 45°)? I found only in UW-9(b) that "the dimensions and shape of the edges to be joined shall be such as to permit complete fusion and complete joint penetrarion". Do you know other references? Or in these cases the guideline is "designed by experience"? tnks

 

[weldstan]

ASME VIII does not require absolute joint geometry designs as you have found in the referenced UW-9.

 

[QCJT]

Hi ElCId,

It's a good question especially because ASME VIII is a design standard. Although there are strength requirements for joints but some guidelines on joint configuration would be also nice.

 

[fleischfresser]

Hi ElCId,

type of butt-weld joint preparation is basic welding / fabrication knowledge had therefore no place on the Code.

Have you ever read the Code? On the Foreword of each Code Section is clear stated:
"The Code does not address all aspects of these activities and those aspects that are not specifically addressed should not be considered prohibited. The Code is not a handbook and cannot replace education, experience, and the use of engineering judgment. The phrase engineering judgement refers to technical judgments made by knowledgeable engineers experienced in the application of the Code."



Regards - Juergen

 

[pradipgoswami]

According to Sec-IX,QW-401.4 Nonessential Variable (Procedure). A change in a welding condition which will not affect the mechanical properties of a weldment (such as joint design, method of back gouging or cleaning, etc.This is the guideline for conventional arc welding processes.Though for non conventional process.g FSW, Laser Welding there are some imposed restrictions.

Joint design(with included angle) used to be restriction imposed by European codes but not by ASME. Having said that the designer has to suggest the best groove for quality and productivity. In a large fabrication organization welding engineer is the additional resource for the same as he or she executes the work on the shop floor.

Thanks.

Pradip Goswami,P.Eng.IWE
Welding & Metallurgical Specialist
Ontario,Canada.
ca.linkedin.com/pub/pradip-goswami/5/985/299

 

[TomBarsh]

kudos to Pradip for directing to ASME B&PV Code Section IX. This is the text that will address rules for joint configuration, welding, etc.

 

[pradipgoswami]

Thank You Tom.
ASME is flexible on this aspect.However the fabricator needs to prove the joint/weldment integrity at the end.For critical joints (saw Narrow GAP SAW/GMAW)in addition to a qualified PQR, shop/ weld mock up coupon may be specified as required.

Pradip Goswami,P.Eng.IWE
Welding & Metallurgical Specialist
Ontario,Canada.
ca.linkedin.com/pub/pradip-goswami/5/985/299