Document bGnEx5zNkx2nradqOmbVVRJ1
Heating Ventilating Air Conditioning Guide 1938
Table 13. Coefficients of Transmission (U) for Pipes Insulated with Laminated Asbestos Type Insulation (Approximately 20 Laminations Per Inch Thickness)
These coefficients are expressed in Btu per hour per square foot of pipe surface per degree Fahrenheit difference in temperature between pipe and surrounding still air at 70 F
Thxcenbbb InHUOLAfTIO` N (Inches)
Pipe . Size* . (Inches)
a
lA
im
ia 2
2A
3
. i 3%
i4
*A
,5 6
8 10 : 12
Hot Water
I
120 F 1 150 P
180 F
210 F | 227.1 F (5 Lb)
Temperature Difference
50 F
0.910 0.823 0.748 0.686 0.649 0.610 0.581 0.558 0.539 0.524 0.514 0.503 0.492 0.473 0.458 0.452
*0F
0.925 0.836 0.760 0.698 0.659 0.620 0.590 0.567 0.548 0.532 0.522 0.511 0.500 0.480 0.465 0.459
110 F
0.940 0.850 0.773 0.710 0.671 0.630 0.600 0.576 0.557 0.541 0.530 0.519 0.509 0.488 0.473 0.467
140F
0.956 0.863 0.785 0.721 0.682 0.640 0.609 0.585 0.566 0.551 0.539 0.528 0.517 0.497 0.481 6.475
157.1 F
0.964 0.871 0.792 0.728 0.688 0.647 0.615 0.591 0.571 0.556 0.544 0.533 0.522 0.502 0.485 0.478
Steam
297.7 K (50 Lb)
227.7 F
1.001 0.902 0.823 0.756 0.716 0.671 0.638 0.613 0.592 0.577 0.564 0.553 0.542 0.521 0.504 0.497
337.9 F (100 Lb)
267.9 F
1.022 0.921 0.840 0.771 0.731 0.685 0.651 0.626 0.604 0.589 0.575 0.565 0.553 0.532 0.514 0.507
A 6.755 . .0.767 0.780 0.793 0.800 0.831 0.848
*A 0.674 0.685 0.697 0.708 0.715 0.743 0.759
l 0.607 0.618 0.628 0.639 0.645 0.670 - 0.684
\A > 0.553 0.562 0.572 0.581 0.587 0.610 0.622
;
XA 5
2 ci
0.517 .0.527 6.481 0.490
0.536 0.499
0.545 0.508
0.550 0.513
0.572 0.535
0.584 0.547
IA ' .0.453 0.460 0.469 0.477 0.481 0.500 0.511
: 3. 0.429 0.436 .0.444 0.452 0.456 0.475 0.485
\a
314 A
0.412 0.419 0.427 0.434 0.438 0.456 0.465 0.400 0.407 0.415 0.422 0.426 0.443 0.453
\ AA
0.390 0.396 0.402 0.409 0.413 0.429 0.437
5
0.380 0.386 0.393 0.400 0.403 0.418 0.427
6 0.369 0.375 0.382 0.389 0.392 0.408 0.417
; :8
0.351 0.358 0.364 0.370 0.374 0.388 0.397
i 10
0.337 0.344 0.350 6.356 0.359 0.373 0.382
.12 ,
0.332 0.338 0.344 0.350 0.353 0.367 0.375
: 14
%
1
tu
ia
.2
; .214
!3
2 3)4
4.
: IA
r
5
. . -i
6
4 r. -8
io /
12.
0.664 0.591 0.529 0.480 0.445 0.412 0.385 0.364 0.346 0.336 0.325 0.316 0.306 0.288 0.275 0.269
0.675 0.601 0.538 0.488 .0.453 0.420 0.392 6/370 0.352 0.342 0.332 0.322 0.312
0.293 0.279 0.274
0.687 0.611 0.547 0.497 0.462 0.427 0.398 0.376 0.358 0.348 0.338 0.327 0.317 0.298 0.284
0.278
0.698 0.621 0.557 0.505 0.470 0.434 0.405 0.382 0.365 0.354
0.343 0.333 0.323 0.303 0.289 0.283
0.704 0.627 0.562
0.510 0.475 0.438 0.409 0.385 0.368 0.357 0.346 0.336 0.326 0.306 0.292 0.286
0.732 0.652 0.584 0.529 0.494 0.455 0.425 0.400 0.382 0.371 0.360 0.349 0,338 0.317 0.302
0.296
0.747 0.665 0.597 0.540 0.504 0.464 0.434 0.408 0.390 0.378 0.367 0.356 0.345 0.324 0.308 0.302
728
Chapter 39. Piping and Duct Insulation
Table 14. Coefficients of Transmission (U) for Pipes Insulated with Rock Wool Type Insulation
These coefficients are .expressed in Btu per hour per square foot of pipe surface per degree Fahrenheit difference in temperature between pipe and surrounding still air at 70 F
Thickness ` Of
Insulation (Inches)
i -
.
2
Nominal Pipe Size
(Inches)
)4
%
1
m
lA
2
m
3
^/4
.4
. AA
.5 ' 6. 8
: 10 12
=
A
1
U4 114
2
VA
3
3)4
4
i'A
5 6 "8 . 10
12
-
-A
ZA
l
1M
lA
2
2A
'3
iA
. 4
4A
5
.6
8 10 12
120 F
50 F
0.631 0.569 0.518 0.476 0.450 0.422 0.402 0.385 0.373 0.363 0.355 0.348 0.341 '0.327 0.317 0.313
Hot Water
Steam
150 F
180 F
210 F
r'227.1 F 1 (5 Lb)
297.7 F 1 337.9 F (50 Lb) (100 Lb)
Temperature Difference
80 F
110 F . 140F
157.1 F 227.7 F . 267.9 ,
0.644 0.658 0.581 0.593 0.529 0.541
0.486 0.497
0.460 0.470 0.431 0.441 0.411 0.420 0.394 0.402
0.381 0.389
0.371 0.379
0.363 0.371
0.356 0.364
0.348 0.356 0.335 0.342
0.324. 0.331 0.320. 0.327
0.672 0.606 0.552 0.507
0.480 0.450 0.428 0.411
0.398 0.387
0.379 0.371
0.363 0.349 0.338 .0.334
0.680 0.613 0.559
0.513
0.485 0.456 0.434 0.415 0.402
0.392 0.383 0.376 0.368 0.353 0.343
0.338 .
0.712
0.642 0.585 0.537
0.508 0.478 0.455 0.435 0:421 0,411 0.402 0.394
0.386 0.372
0.360 0.355
0.730
0.659 0.600 0.551 0.522 0.490 0.466
0.446 0.432 0.422
0.413. 0.404 0.396 0.381
0.369 0.364
0.523
0.468 0.421
0.383 0.359
0.333 0.314 0.296 0.286
0.278 0.270 0.263 0.257 0.244 O'. 235
0.230
0.534 0.477
0.430 0.391
0.366 0.340 0.320 0.302 0 i 291 0.284 0.276 0.269 0.262
0.249 0,240
0.234
0.545 0.487
0.440 0.399 0.375 0.348 0.327 0.310 0.298 0.290 0.282.
0.275
0.267 0.254 0.245 0.239
0.556 0.497 0.449 0.407 0.383
0.356 0.335
0.317 0.304 0.296 0.287
0.280 0.273 0.260 0.250
0.245
0.563 0.503 0.455 0.412
0.387 0.360 0.339 0.321 0.307
0.300 0.291 0.284
0.277 0.263 0.253 0.247
0.590
0.528 0.477 0.433 0.407
0.378 0.355 0.337
0.323 0.315 0.305 0.298 0.290
0.276 ' 41.265; 0.260
0.606 0.542. 0.490 0.444
0.419 0.389, 0.365 0.347 0.332 0.323 0.313
0.305 0.297 0.283 0.272.
0.267
0.461 0.409
0.366 0.333 0.310 0.286 0.268 0.252 0.241 0.232 0.225 0.218 0.213 0.200 0.189 0.185
0.471 0.418 0.374 0.340 0.316 0.292 0.274 0.257 0.246 0.237 0.230 0.223 0.217 0.204 0.193 0.190
0.481 0.427 0.382 0.347 0.323 0.298 0.279 0.262 0.251 0.242 0.235 0.228 0.221
0.208 0.197 0.194
0.491
0.436 0.390 0.355 0.330 0.304 0.285 0.268 0.257 0.247 0.240 0.233 0.226 0.213 0.-201 0.198
0.496 0.441
0.395 0.359
0.334 0.308 0.289 0.272 0.260 0.250 0.243 0.236 0.228 0.215 0.204 . 0.200
0.520 0.534 0.463 0.475 0.415 0.427 i 0.377 0.387
0.351 0.360 0.323 0.331 : 0.302 0.310 : 0.284 0.292 0.272 . 0.280 0.262 0:269 0.255 0.262 0.247 0.253 0.239 0.245 0.225 0.231 0.214 0.220 0.210 0.216