TM 55-203
CHAPTER 20
WELDING
Section I. GENERAL
20-3. Heat Treatment After Welding
20-1. Preparation
a.
Parts for which annealing, normalizing, or
Welding by any process requires the utmost care and
good judgment on the part of the welding operator The
stress-relieving is required should be heated to the
operator's ability to perform the work in question
required temperature at a rate not exceeding an
satisfactorily by the process selected must be
increase of 500F temperature per hour and held at the
ascertained by the officer in charge of the shop. The
specified temperature 1 hour for each inch of maximum
edges of pieces to be welded must be prepared as
thickness of material. Material must not be charged into
shown in figure 20-1. If both sides of the fractured
the furnace initially, if the furnace temperature exceeds
member can be worked upon, the fracture should be
700 F. Furnace and material temperatures must be
prepared as in figure 20-1(1) When only one side of the
measured with pyrometers (recording pyrometers
fractured member is accessible, figure 20-1(2) should be
preferred).
followed. The entire crack or fracture, must be cut out
with a cutting torch or chipped or ground out for a
b.
The annealing temperature should be 1500
sufficient distance, so that no portion of the crack
to 1600 F The material should be allowed to cool to a
remains. The surfaces upon which new material is to be
temperature of 500 F. or lower in the annealing
deposited must be clean and reasonably smooth. If the
furnace.
surfaces are prepared by flame-cutting, the oxide scale
must be removed before welding is started On
c.
The normalizing temperature should be
malleable iron or cast iron, any flame-cut surface and
1500 to 16000F. Material removed from the furnace
0
affected area must be removed by chipping or grinding.
at about this temperature and allowed to cool in shop air
Particular attention must be given to running boards,
should be protected from drafts and weather.
brake and dome steps, and platforms to insure that all
the galvanized metal has been removed.
d.
The stress-relieving temperature should be
1200 to 1250 F. If a furnace is used, the material
20-2. Welding Methods
should be removed and allowed to cool in still air Local
stress relieving of material is permissible by heating the
Generally, it is good practice to employ multiple pass
part to a red heat with a blowtorch and allowing It to cool
welding in layers approximately 1/8 inch thick laid with a
in place.
slight oscillating movement of the electrode.
In
oxyacetylene welding or bronze welding, the weld
e.
When truck side frames, bolsters, or the
deposit should be made with a single pass. Complete
knuckle sidewall of coupler heads are welded, a record
welds should follow the contours shown in figure 20-2
must be stamped by at least 3/8-inch stencils on the
Heavy reinforcement is neither necessary nor desirable.
weld or immediately adjacent thereto (surface of part to
The weld should be finished so as not to produce a
be smoothed off by grinding or other means before
notch effect at the junction of the weld with the parent
stamping) to indicate the organization reporting marks,
material, and every precaution should be taken to avoid
the date, shop identifying symbol, and welder's
abrupt changes in section thickness at the line of fusion
identification number or mark. These markings should
The deposited metal must be dressed to the required
be in the following form:
dimensions After welding has been completed on
running boards, brake and dome steps, and platforms,
Reporting marks__________________________
all iron oxide scale must be removed and a protective
Shop identifying symbol____________________
coating applied.
Date____________________________________
Welder's mark____________________________
20-1
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