Document 6BDEyVO5y71a9M0G3NwmpE3Ng
American Society of Heating and Ventilating Engineers Guide,'1936
Table 7. Coefficients of Transmission (U) for Pipes Insulated with Corrugated Asbestos Type Insulation (4 Plies 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
Thickness
or
Inbulation (Inches)
i
14
2
Pipe Size (Inches)
4 y i i \i 14 2 24 3 3y2 4 44. 5 6 8 10 12
Yi Y
l
1Y
2 24
3
34 4 44
5 6 8
10
12
4 M
1
lY 14
2
2Yi
3
34
4
4)4
5 6 8
10
12
Hot Water 120 F | ISO F | 180 P
210 F
227.1 F (5 Lb)
50 F
80 F
Temperature Difference
HOP
140 F
157.1
0.890 0.803 0.731 0.671 0.635 0.595 0.567 0.544 0.527 0.513 0.502 0.490 0.480 0.462 0.447 0.441
0.919 0.829 0.756 0.693 0.656 0.615 0.586 0:562 0.544 0.530 0.518 0.507 0.496 0.477 0.462 0.456
0.949 0.857 0.780 0.716 0.677 0.635 0.605 0.580 0.561 0.548 0.535 0.523 0.512 0.493 0.476 0.470
0.978 0.883 0.804 0.738 0.698 0.656 0.624 0.598 0.578 0.565 0.551 0.539 0.528 0.508 0.491 0.485
0.995 0.898 0.818 0.751 0.710 0.667 0.635 0.608 0.588 0.575 0.561 0.549 0.538 0.517 0.500 0.493
Steam
297.7" (50 Lb)
227.7
1.065 0.961 0.876 0.804 0.760 0.715 0.680 0.652 0.631 0.616 0.601 0.588 0.577 0.554 0.537 0.529
337.9 F (100 Lb)
267^9F
1.106 0.997 0.909 0.834 0.788 0.742 0.705 0.677 0.654 0.639 0.624 0.611 0.599 0.575 0.557 0.550
0.737 0.657 0.594 0.542 0.507 0.471 0.443 0.421 0.403 0.393 0.383 0.372 0.362 0.343, 0.328 0.323
0.762 0.679 0.614 0.559 0.524 0.487 0.458 0.435 0.417 0.405 0.394 0.384 0.374 0.354 0.339 0.334
0.787 0.702 0.634 0.577 0.541 0.503 0.473 0.449 0.430 0.418 0.407 0.397 0.387 0.366 0.351 0.346
0.812 0.725 0.654 0.596 0.558 0.519 0.488 0.463 0.443 0.432 0.420 0.409 0.399 0.378 0.362 0.357
0.826 0.737 0.666 0.606 0.568 0.528 0.497 0.472 0.451 0.439 0.428 0.417 0.406 0.385 0.369 0.364
0.884 0.790 0.713 0.649 0.609 0.565 0.533 0.506 0.483 0.471 0.460 0.447 0.436 0.413 0.397 0.391
0.918 0.820 0.740 0.673 0.632 0.587 0.553 0.525. 0.502 0.489 0.476 0.463 0.452 0.429 0.413 0.407
0.648 0.578 0.518 0.469 0.438 0.404 0.379 0.356 0.339 0.328 0.318 0.308 0.299 0.282 0.267 0.263
0.670 0.598 0.535 0.485 0.452 0.417 0.391 0.367. 0.350 0.339 0.328 0.318 0.309 0.291 0.276 0.272
0.692 0.713 0.726
0.617 0.637 0.648 0.552 0.570 0.580 0.501 0.517 0.527 0.467 0.481 0.490 0.430 0.444 0.452 0.403 0.415 0.422 0.378 0.390 0.397 0.361 0.373 0.380 0.350 0.360 0.367 0.339 0.350 0.357
0.329 0.340 0.346 0.319 0.329 0.335 0.301 0.310 0.315 0.285 0.294 0.299 0.280 | 0.289 l 0.294
0.779 0.694 0.622
0.566 0.526 .0.483 0.451 0.425 0.406 0.392 0.381 0.370 0.358 0.336 0.319 0.314..
0.810 0.720 0.645 0.587 0.545 0.502 0.466 0.440 0.421 0.406 0.395 0.384 0.371 0.349 0.332 0.325
658
Chapter 36--Insulation of Piping
Table 8. Coefficients of Transmission (U) for Pipes Insulated with Corrugated
Asbestos Type Insulation (8 Plies Per Inch Thickness)
r
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
or
Insulation (Inches)
i
14
2
Nominal PtPB Size
(Inches)
4 Y
l
lY 14
2
24
3
34
4
44
5 6 8 10 12
4 Y
1
lY 14
2
24
3
34
4 44 5 6 8 10 12
4 Y l iY 14 2 24
3
34
4 44 5 6
8
10 12
120 F
50 P
0.801 0.723 0.658 0.606 0.573 0.538 0.511 0.489 0.474 0.461 0.451 0.442 0.432 0.416 0.402 0.397
Hot Water
ISO F
180 F
210 F
227.1 V (5 Lb)
Temperature Difference
80 F ^ HOF
140 F 157.1 F
0.820 0.739 0.673 0.619 0.586 0.550 0.523 0.501 0.485 0.472 0.462 0.452 0.442 0.426 0.412 0.406
0.838 0.756 0.688 0.633
0.599 0.562 0.534 0.512 0.496 0.482 0.472 0.462 0.452 0.436 0.421 0.415
0.857 0.773 0.704
0.647 0.612 0.575 0.546 0.524 0.507 0.493 0.482 0.473 0.463 0.446 0.430 0.424
0.868 0.783 0.713 0.655 0.619 0.581 0.553 0.531 0.514 0.500 0.489 0.479 0.468 0.451 0.435 0.429
Steam
297.7 F | 337.9 F (SO Lb) (100 Lb)
227.7 F
0.913 0.824 0.751 0.688 0.652 0.612 0.582 0.558 0.542 0.527 0.515 0.505 0.493 0.475 0.459 0.452
267.9 F
0.939 0.847 0.772 0.707 0.670 0.629 0.599 0.575 0.557 0.542 0.530 0.520 0.508 0.489 0.473 0.466
0.664 0.593 0.535 0.488 0.457 0.425 0.399 0.378 0.363 0.353 0.343 0.334 0.325 0.309 0.295 0.291
0.679 0.607 0.547 0.499 0.467 0.434 0.408 0.387 0.371 0.361 0.351 0.342 0.333 0.316 0.303 0.298
0.695 0.621 0.560 0.510 0.478 0.444 0.418 0.396 0.380 0.369 0.360 0.350 0.341 0.324 0.310 0.306
0.711 0.636 0.573 0.522 0.490 0.455 0.428 0.405 0.388 0.378 0.368 0.358 0.349 0.332
0.318 0.313
0.720 0.643 0.580 0.528 0.496 0.460 0.434 0.411 0.393 0.383 0.373 0.363 .0.353 0.336 0.322 0.317.
0.759 0.677 0.611 0.556 0.522 0.485 0.457 0.433 0.415 0.403 0.393 0.383 0.373 0.355 0.340 0.335
0.780 0.697 0.629 0.572 0.537 0.499 0.471 0.446 0.427 0.415 0.404 0.394 0.383 0.365 0.350 0.344
0.585 0.520 0.465 0.422 0.394 0.364 0.339 0.319 0.304 0.295 0.285 0.278 0.269 0.253 0.240 0.236
0.599 0.533 0.476 0.432 0.403 0.372 0.347 0.327 0.311 0.302 0.292 0.284 0.275 0.259 0.245 0.241
0.613 0.545 0.487 0.442 0.412 0.380 0.355 0.334
0.318 0.308 0.299 0.290 0.282
0.265 0.251 0.247
0.627 0.635 0.558 0.565 0.498 0.504 0.452 0.458 0.422 0.427
0.388 0.393 0.363 0.367 0.342 0.346 0.326 0.330
0.315 0.319 0.306 0.310 0.297 0.301 0.288 1 0.292
0.270 I 0.273
0.257 0.260
0.253 1 0.256
0.668 0.595 0.532 0.483 0.450 0.415 0.387 0.365 0.349 0.336 0.327 0.317 0.307
0.288 0.275 0.270
0.688 0.612 0.547 0.497 0.462 0.427 0.398 0.375 0.358 0.345 0.336 0.326 0.315 0.296 0.282 0.277
659