MCG
MEP DEP.
MECH SECTION
MENTOR
.CONSULTING GROUP.
ABO-HOMOS Hospital
Pressurization Unit Calculations
‫أﺑﻮ ﺣﻤﺺ‬
‫وع ﻣﺴ ﺸ‬
‫ﻣ‬
PIPE TAKE OFF
HVAC‐HVAC PIPE TAKE OFF
Supply , install , flushing and testing of
ERW pipes schedule 40 , comply with
ASTM A 53 for external piping works
complete with fitting , joints , connection
, network valves and accessoris , sleeves ,
expansion joint , supports , Identifications
, painting, and including all items
mentioned in Drawings , specifications
and method of measurments .
ITEM
Size (mm)
Length (m)
Safety (%)
Total Length (m)
Chilled Water (Black Steel)
Pipe Diameter 3/4''
Pipe Diameter 1''
Pipe Diameter 1 1/4''
Pipe Diameter 1 1/2''
Pipe Diameter 2''
Pipe Diameter 2 1/2''
Pipe Diameter 3''
Pipe Diameter 4''
Pipe Diameter 6''
Pipe Diameter 8''
Pipe Diameter 10''
Pipe Diameter 12''
Pipe Diameter 18''
Pipe Diameter 20''
ø20
ø25
ø32
ø40
ø50
ø65
ø80
ø100
ø150
ø200
ø250
ø300
ø450
ø500
1286.62
1542.28
927.53
725.18
814.17
489.45
672.50
468.39
248.41
59.76
245
20
100
118
20
20
20
20
20
20
20
20
20
20
20
20
20
20
1544
1851
1113
870
977
587
807
562
298
72
294
25
120
140
ø150
ø250
ø300
ø400
ø450
30.23
327.52
8.19
11.73
167.85
20
20
20
20
20
36
393
10
14
201
Total Volume (L)
485
909
895
1093
1918
1948
4056
4414
5266
2262
14431
1767
19085
27488
Chilled Water (Pre‐insulated burried)
Pipe Diameter 6''
Pipe Diameter 10''
Pipe Diameter 12''
Pipe Diameter 16''
Pipe Diameter 18''
Total
636
19290
707
1760
31967
140377
Item
Quantity
3
Total
Total + 20%
Chillers
Unit Volume (L)
Total Volume (L)
191
573.00
573.00
687.60
Item
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
2
43
Total
Total + 20%
AHU
Total Volume (L)
47.74
11.58
23.3
14.1
23.3
71.53
30.25
30.22
100.86
15.75
38.13
58.41
11.58
58.41
41.99
50.29
58.37
66.53
19.68
19.68
41.97
41.97
14.1
11.58
19.03
58.37
20.54
20.54
20.54
19.68
19.68
41.97
47.74
19.03
47.74
47.74
11.58
21.92
58.41
72.62
11.58
11.58
11.58
1483.19
1779.83
Item
Quantity
181
60
89
62
49
55
Total
Total + 20%
Item
Total
FCU
Unit Volume (L)
1.87
2.26
3.19
4.3
4.75
6
Total Volume (L)
338.47
135.60
283.91
266.60
232.75
330.00
338.47
406.16
All System
143250.59
Design calculation sheet
Project no.
Date:
Sheet no.:
1
of
1
Subject:
Computed by:
Checked by:
Approved by:
Diaphragm type Closed Expansion Tank sizing
Sizing is based on ASHRAE 200 HVAC Sytems & Equipment, Chap 12, Hydronic Heating & Cooling System Design
Vt  VS 
Vt
Vs
t1
t2
Pa
Pi
P1
=
=
=
=
=
=
=
Pmax
P2
=
=

=

=
[( 2  1 )  1]  3    T
1  ( P1 P2 )
Volume of expansion tank
Volume of water in system
Lower temperature
Higher Temperature
Atmospheric Pressure
Initial Fill or minumium Pressure at tank
Absolute Pressure at lower
temperature (Pi + Pa )
Maximum System Allowable Pressure
Absolute Pressure at higher
temperature (Pmax + Pa )
Specific volume of water
at lower temperature
Specific volume of water
at higher temperature
(gal)
(gal)
(ºF)
(ºF)
(psia)
(psig)
(psia)
=
=
=
=
=
37,842
42
88
14.7
76.5
91.2
(psig)
(psia)
=
125
139.7
(ft3/lb)
=
0.01602
(ft3/lb)
=
0.01609

=
1.004%
( 5.6 ºC)
( 31.2 ºC)
( 5.3 bars)
( 8.7 bars)

=
Linear Coefficient of thermal expansion
for steel
(in/in.ºF) =
6.5E-06
Vt
=
37842 x [( 0.01609 / 0.01602) - 1 ] 1
(
( 3 x 6.5E-06
91.2
/
x ( 88 - 42 ))
139.7 )
Vt
=
379
gal
Selected Tank Capacity:
=
1433
liters
1
Tank
2000
Note to user: Selection shall be based upon actual
catalogue data as available from various.
manufacturers.
Liters