Document Bwd2EDLd7gBe12bZezE03Jo4
HEATINC VENTILATING AIR CONDITIONING GUIDE 1944
is dependent on the individual job, the use of welding is generally recom mended on the basis of a greatly reduced cost of maintenance and repair, of less weight resulting from the use of a lighter-weight pipe, and of increased economy in pipe insulation, hangers, and supports rather than on the basis of any economy that might be effected in actual erection by welding on low to medium pressure heating jobs.
Fusion welding, commonly used in erection of piping, is defined as the process of joining metal parts in the molten, or molten and vapor states,
Table ,8.
American Standard Dimensions for Butt-Welding Elbows, Tees, Caps, and Lapped-Joint Stub Ends, A.S.A. B16.9-1940
Nominal Pipe
- Size
Outside Diameter.
i
134 134
2
234
3
334 4
5 6 8 10 12
1.315 1.660 1.900 2.375 2.875 3.500 4.000 4.500 5.563 6.625 8.625 10.750 12.750
Cshteb-to-End
90-Deg Elbows
A
mm
234
3
354
4H
534
6 734 9 12 15 18
45-Deg.. Elbows
B
34
l
immys
2
234
2m34
354
5
634 734
Of Run Tee C*
134 134 234 234
3
3 34 334 434 434 534
7
834 10
Caps
2Jb-o
Lapped-Joint Stub Ends
Length Fh
R&dius of
Fillet R
Diam. of Lap Gd
134 4
134 4
1m34
4 6
134 6 26
234. 6
234. 6
38
334 8
48
5 --10
6 10
34 2 Me 234 34 234 Me 334 Me 434 34 5 34 534 Me 5Me Me 7Me 34 834 34 1034 34 1234 34 15
All dimensions given in inches.
aThe dimensions of welding tees cover those which have side outlets from one size less than half the size of the run-way opening of the tees to full size.
bDimensions E and F are applicable only to these fittings in schedules up to and including Schedule 80 A-S.A. Standard B36.10-1939.
oThe shape of these caps shall be ellipsoidal and shall conform to the requirements of the AS.M.B. Boiler Construction Code.
dThis dimension is for standard machined facings in accordance with American Standard for Steel Pipe Flanges and Flanged Fittings (A.S.A. B16e-1939). The back face of the lap shall be machined to conform to the surface of the flange on which it seats. Where ring joint facings are to be applied, use dimension K as given in AA. B16e-1939..
without the application of mechanical pressure or blows. Fusion welding embraces gas welding and electric arc welding, both of which are com monly used to produce acceptable welds.
Welding application requires the same basic knowledge of design as do the other types of assembly, but in addition, requires a generous know ledge of the sciences involved, particularly as to welding qualities of metal, their reaction to extremely high temperatures, and the ability to determine and use only the best quality welding rods. This requirement
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CHAPTER 17. PIPE, FITTINGS, WELDINC -
applies equally to employer and employee with the employer accepting all of the responsibility. Thus the employer should select his welding mechanics with good judgment, provide them with first-class equipment and tools, arrange for their training and use of acceptable workmanship
Table 9. American Standard Dimensions of Steel Welding Neck and Slip-on Welding Flanges for Steam Service Pressure Rating of 150 Lb per Sq In. (Gage) at a Temperature of 500 F, and 100 Lb per Sq In. (Gage) at 750 F, A.5.A.
B16e-1939
--------------------------- X----------------- -
p---------------------- VV
1
yt
Y
^ 1________
WELDING NECK
SLIP-ON WELDING
Nominal Pipe . Size
OP OP OPDiameter Thickness Diameter
Flange
Flg. Min.
Hub
Hub Diam.
Beginning
op. ChamfehL-
Length Thru Hub*
Inside Diam. op Pipe
Schedule 40
Bore op 8lif-on Flanges
Min.
Dlam. op No. Sesb
' Bolt
op
op .
Circle Bolts Bolts
.0
Q .X
. H :Y
J.. W
34 34 l
A34
134 2
234 3
334 4 5 6 8 ; 10 12 14 O.D. 16 O.Dr 18 O.D. 20 O.D. 24 O.D.
334 i
m
334 -34
.1-34-
434 % il'Ms
434 34 23(6 5 % : 2%
6 34 . 3%
7 Vs .3%
.'734
434 .
834 - % 4%
9 m \5Me io % m: 11 : 1 . m
1334 134
,9%
16 134s, 12
19 21
2334
134 liVs lYs 1554 I34e . 18
25 . m im 2734 1% 22
32 134 2634
0.84:
1.05 1.32 . 1.66 1.90:
2.38 2.88' 3.50
4.00:
4:50: 5.56: 6.63:
8.631 10:75;
i2.75 14.00 16.00 18.00 20.00 24.00.
134 0.62*:2Hu 0.82* 2Me . 1.05* . 234 1.38* 2Ve 1.61* 234 2.07* 2M 2.47* 2 34 3.07* 2% . 3.55* 3 4.03*
334 5.05* 3M 6.07* 4 : 7.98* 4 10.02*
4 34 5 5. .
534 s% 6
To Be . Specified
by ' Purchaser
0.88 234 4 1.09 234 4
1.38 3ys 4-
1.72 334 4
1.97 3`/s 4
2.44 434 4 2.94 534 4-
3:56 6
4
4.06 . 7 ' 8
4.56 734. 8:
5.66 834 8> 6.72 934. 8.
8.72 1134 8:
10.88 1434 .12
12.88 17 12.
14.19 1854 12
16.19 2134. 16
18.19 2234 16
20.19 25 20
24.19 29Ji 20
34 34 34 34 34
H
Vs Vs Vs Vs
34 34 54 Vs Vs 1
1
134 1 ys 134
All dimensions given in inches.
.
aA raised face of Hi in. is included in thickness offlange minimum and in length through hub.
bThe outside surface of the welding end of the hub shall be straight or tapered at not more than 6 deg.
^Dimensions H and J correspond to the outside and inside diameters of pipe as given in A S.A. B36.10-
1939, Schedule 40.
.
. /
These diameters are identical with the diameters of what was formerly designated as Standard Weight.
Pipe of the corresponding sizes.
standards, and at regular intervals subject their, work to prescribed tests. Industry will not .accept the. employment of'mechanics of.undetermined: ability nor on the basis of past experience. Neitheridoes industry accept the statement that a weld is only as good" as the. workman who makes it.:
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