CEMP-E
TI 809-26
1 March 2000
CHAPTER 5
DESIGN FOR WELDING
1. GENERAL.
a. Engineer's Responsibility. The Engineer is responsible for the analysis and design of the
connection, including connections between elements in built-up members. Critical structural steel
connections must be completely detailed and shown on the contract drawings. The Engineer may
prescribe connection details, if desired or necessary, but generally it is best to allow the fabricator or
erector to select the specific welding detail to be used for a particular joint. For instance, it may be
adequate for the Engineer to specify a Complete Joint Penetration (CJP) groove weld, or specify a
Partial Joint Penetration (PJP) groove weld and state the required throat. This may effectively be done
through the use of AWS welding symbols, and when necessary for prequalified groove welds, the
appropriate AWS designation. The fabricator and erector are typically in the best position to select which
process, groove type (single, double, bevel, vee, J, U), and groove angle should be used based upon
economics, availability of equipment and personnel, distortion control, and ease of welding operations.
The Engineer must review and approve the final details selected by the contractor.
2. GOOD DESIGN PRACTICE.
a. Availability of Materials, Equipment and Personnel. In the selection of base metals, welding
processes, filler metals, and joint designs, one should consider the availability of the structural steel,
welding equipment, filler metals, personnel qualified to perform such welding, personnel qualified to
inspect the welding, and NDT equipment and personnel necessary to perform NDT as required. Certain
welded joint designs may require notch-tough filler materials, welding personnel qualified in out-of-
position welding, welders qualified for specific processes, enclosures for field welding, or nondestructive
testing. When the availability of any of the above is in question, alternative joint designs should be
investigated.
b. Access. The following items should be considered to permit welding operations to be made with
adequate quality:
(1) Welding personnel must have direct visual access to the root of the weld. All passes must be
visually monitored by the welder during welding.
(2) Access should be adequate so that the welding electrode can be positioned at the proper angle
for proper penetration and fusion. Generally, the electrode should be positioned so that the angle
between the part and the electrode is not less than 30o. Smaller angles may cause a lack of fusion along
the weld / base metal interface. Access should be checked at the design stage when welding in highly
confined spaces or with closely spaced parts.
(3) Weld access holes, placed in beam and girder webs when splicing flanges or making beam-to-
column moment connections, must be of adequate size to permit the weld to be placed by reaching
through the access hole with the electrode. Minimum access hole sizes are specified in AWS D1.1
Figure 5.2. Larger access holes may be warranted based upon the welding process and type of welding
equipment used.
5-1
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