| Tweet |
Custom Search
|
|
|
||
 TB 55-1900-201-45/1
E-27.
Cropping and Renewing.
a. In the case of structural members such as frames, beams, stiffeners, etc., it is a practical repair measure to crop
out the distorted or wasted section of the member, the outer flange for ex- ample, and replace with new material. Where
this method is used, the following conditions should prevail:
(1) There should be sufficient material in the remaining portion of the member to permit sound attachment of the
new metal.
(2) The new portion should be in good alignment with the adjoining old portion. Particular care should be exer-
cised in this regard in way of flanges.
(3) There should be sufficient clearance to permit the making of good welds. If this is not the case, the member
should be renewed.
(4) If the attachment of the member to the adjoining plat- ing is by riveting, the joint will have to be checked for
tightness and corrected as necessary after completion of welding.
SECTION V. Welding
E-28. General. Section 26, Parts I and III of the American Bureau of Shipping Rules for Building and Classing Steel
Vessels contains the requirements and instructions for the production of acceptable hull welds and the qualification of
welders. These rules are not repeated here because they are available to and should be used by inspectors engaged in
construction or repair work. Some points which require special note are discussed in the following paragraphs.
E-29. Welders. In view of the importance of obtaining sound welds in repair work, normally only welders qualified by
the Coast Guard, the American Bureau of Shipping or the Naval Ships Systems Command (Navy Department) should be
employed. In some cases, qualification by other government agencies or fabricators may be acceptable. Cases of this
nature should be referred to the Commandant (MMT) for resolution.
E-30.
Steel.
a. Steel plate and shapes which are to be welded should meet the applicable requirements for structural steel for
hulls as set forth in Section 39 of the American Bureau of Shipping Rules for Building and Classing Steel Vessels. Half
rounds, rounds and bulb bars are frequently produced from Bessemer steel which is not permitted by American Bureau of
Shipping Rules due to the likelihood that such steel may be very notch sensitive at ordinary operating temperatures. All
ship steel, including the above items must be made by the open hearth, basic oxygen, electric furnace of such other
process as may be specifically approved. The ends of half- rounds and bulbs should be kept clear of existing structural
E-20
|
||
|
||
