INSTRUCTIONS
ORIFICE METERS
WARNING
These instructions are intended for use only by experienced, qualified
combustion start-up personnel.
Adjustment of this equipment and its components, by unqualified personnel,
can result in fire, explosion, severe personal injury, or even death.
TABLE OF CONTENTS
Subject
A.
B.
C.
D.
E.
F.
Page
General Information..............................................................................................…… 2
Receiving and Inspection.....................................................................................…… 2
Installation..............................................................................................................….. 3
Manometer Adjustment...........................................................................................…. 3
Operation................................................................................................................…. 3
Maintenance............................................................................................................…. 4
Attached: Hauck Orifice Meter Capacity Charts
These instructions are intended to serve as guidelines covering the installation, operation, and maintenance of Hauck equipment. While
every attempt has been made to ensure completeness, unforeseen or unspecified applications, details, and variations may preclude
covering every possible contingency. WARNING: TO PREVENT THE POSSIBILITY OF SERIOUS BODILY INJURY, DO NOT USE OR
OPERATE ANY EQUIPMENT OR COMPONENT WITH ANY PARTS REMOVED OR ANY PARTS NOT APPROVED BY THE
MANUFACTURER. Should further information be required or desired or should particular problems arise which are not covered
sufficiently for the purchaser's purpose, contact Hauck Mfg. Co.
HAUCK MANUFACTURING CO., 100 North Harris Street Cleona, PA 17042 717-272-3051
4/14
www.hauckburner.com
Fax: 717-273-9882
OMG-9
Page 2
OMG-9
A.
GENERAL INFORMATION
The Hauck Orifice Metering System is a family of assemblies of threaded or welded design used for
measuring the flow of either combustion air or any industrial gas. These meters may be used in the
main gas and air lines or in the gas and air lines of individual burners. The former configuration
allows the monitoring of total flow while the latter method allows precise setting of each burner.
B.
RECEIVING AND INSPECTION
Upon receipt, check each item on the bill of lading/and or invoice to determine that all equipment has
been received. A careful examination of all parts should be made to ascertain if there has been any
damage in shipment.
IMPORTANT
If the installation is delayed and the equipment is
stored outside, provide adequate protection as
dictated by climate and period of exposure.
Special care should be given to all motors and
bearings, if applicable, to protect them from rain or
excessive moisture.
C.
INSTALLATION
1.
Install the orifice meter in any position in the appropriate line. Most orifice meters are available
in either of two configurations: one designed specifically for a welded connection, the other for
a threaded female connection. The location chosen for installation should permit easy access
to both pressure cocks and allow sufficient space to remove the orifice plate, if required.
When used in the gas and air lines of individual burners, mount the orifice meter between a
flow control valve and the burner.
NOTE
For maximum accuracy provide 10 pipe diameters
of straight piping without fittings immediately
preceding the orifice meter and 5 pipe diameters
downstream of the orifice.
2.
Insert and loosely tighten the three (3) connecting bolts not required to hold the orifice plate
in position.
3.
Insert the orifice plate and secure it in place by insertion of the fourth connecting bolt.
Page 3
OMG-9
4.
Firmly tighten all bolts.
5.
Insert a threaded plug in the unused cock openings.
D.
MANOMETER ADJUSTMENT
1.
Place the manometer on a rigid support.
2.
Insert the proper amount of fluid into the manometer and adjust the fluid height until a 0.0"
manometer reading is obtained.
3.
Connect the orifice meter pressure cocks to the manometer, using EQUAL lengths of vinyl tubing, such as Tygon, or equivalent.
E.
OPERATION
The orifice metering system is designed so that the specific water column (wc) differential observed
on the manometer corresponds to a specific flow rate through the orifice (for the specific plate being
used).
1.
Fully open the orifice meter pressure cocks.
Page 4
OMG-9
NOTE
To reduce the risk of "blowing" the manometer
(forcing the fluid out of the manometer into the
tubing) tubing clips or valves can be located in
the vinyl tubing lines near the manometer.
The clips or valves are first closed and then
the orifice meter cocks are opened. The clips
or valves are then opened. Locating the
shutoff near the manometer minimizes the gas
volume being compressed when the opposite
leg of the manometer is opened to system
pressure.
Reducing this volume limits movement of fluid
in the manometer.
2.
Read the water column differential in inches and tenths of an inch. If the reading differs from
the desired reading, adjust the flow control valve until the manometer coincides with the desired reading.
3.
Fully close the orifice meter pressure cocks (and tubing clips if applicable).
4.
Disconnect the connecting tubing, if desired.
F.
MAINTENANCE
The design of the orifice plate and brackets requires no service or maintenance.
If it ever becomes necessary to change the orifice plate:
1. Loosen all four (4) connecting bolts.
2. Completely remove the plate positioning bolt.
3. Remove the old plate and insert the new one.
4. Securely tighten all connecting bolts.
Periodically check the quantity of fluid in the manometer and refill as required.
Page 5
OMG-9
OMG SERIES ORIFICE METERS
AIR & NATURAL GAS FLOW CAPACITY (SCFH)
100 – 200 Series Threaded / Weld-In
3/8" Through 1 ½" Pipe Size
Pipe
Size
OMG
Model
Number
3/8"
103
1/2"
105
3/4"
107
1"
110
1 ¼"
112
1 ½"
115
Orifice
Bore
Size
0.197
0.232
0.266
0.307
0.350
0.232
0.266
0.317
0.368
0.423
0.273
0.324
0.379
0.437
0.508
0.585
0.324
0.384
0.452
0.523
0.613
0.715
0.456
0.533
0.630
0.735
0.850
0.986
0.533
0.635
0.744
0.867
1.005
1.156
Air
0.5"
1"
3"
w.c.P w.c.P w.c.P
33
57
24
33
46
80
44
62
107
61
85
147
84
118
203
45
78
32
42
60
103
61
86
149
85
120
206
118
166
286
62
107
44
62
87
151
86
121
208
116
163
282
162
228
394
221
322
555
86
149
61
86
122
210
120
170
293
163
230
398
231
326
562
331
467
806
120
170
294
165
233
403
233
330
570
324
457
790
447
632
1092
641
905
1564
164
232
400
234
331
572
325
459
794
450
636
1100
626
885
1530
881
1245
2151
5"
w.c.P
73
103
137
189
261
100
133
191
265
368
137
194
268
363
507
714
192
270
378
513
724
1039
379
520
734
1018
1407
2015
516
737
1023
1417
1972
2771
Natural Gas
3"
0.5"
1"
w.c.P w.c.P w.c.P
30
43
73
42
60
103
57
80
137
78
110
189
108
152
262
41
58
100
55
77
133
79
111
192
109
154
266
152
214
369
57
80
137
80
113
194
110
156
269
149
211
363
208
294
508
294
415
716
79
111
192
111
157
271
155
219
378
211
297
513
297
420
725
427
602
1040
155
219
379
213
301
520
301
425
735
418
590
1020
577
815
1409
827
1168
2018
212
299
517
302
427
738
419
593
1024
581
821
1419
808
1142
1974
1137
1607
2776
5"
w.c.P
94
132
177
244
336
129
171
247
342
475
177
250
346
468
654
921
247
349
487
661
935
1340
488
671
947
1314
1816
2600
666
951
1320
1829
2544
3576
Notes:
1.
2.
3.
4.
5.
Orifice Bore Size Equals The Orifice Plate Inside Diameter. All Bore Sizes In Inches. Pipe Size Equals Schedule 40 Pipe.
Capacity Based On 60F @ 1 psig Upstream Pressure. Natural Gas Specific Gravity At 0.60; Air Specific Gravity At 1.0.
1__ Model Number Designates NPT Threaded Connection. 2__ Model Number Designates Weld-In Connection.
All Flow Rates At Standard Barometric Pressure: 29.92" Hg (Sea Level).
Design Capacity Is Based On 3" W.C.P.
Continued
Page 6
OMG-9
OMG SERIES ORIFICE METERS
AIR & NATURAL GAS FLOW CAPACITY (SCFH)
100 – 200 Series Threaded / Weld-In
2" Through 6" Pipe Size
Pipe
Size
OMG
Model
Number
2"
120
2 ½"
125
3"
130/230
4"
240
6"
260
Orifice
Bore
Size
0.640
0.754
0.875
1.034
1.203
1.375
0.754
0.890
1.048
1.236
1.423
1.625
0.894
1.056
1.252
1.452
1.688
1.963
1.261
1.470
1.722
2.029
2.345
2.691
1.735
2.067
2.437
2.879
3.314
3.850
4.388
Air
0.5"
w.c.
P
238
334
455
650
911
1250
330
464
651
926
1266
1730
462
649
923
1262
1753
2483
919
1258
1748
2479
3418
4731
1729
2470
3468
4924
6685
9423
13055
1"
w.c.
P
335
470
640
914
1278
1753
465
652
916
1302
1778
2428
651
914
1300
1776
2466
3489
1295
1773
2462
3491
4810
6655
2439
3484
4890
6941
9420
13272
18381
3"
w.c.P
5"
w.c.P
0.5"
w.c.P
577
808
1100
1568
2192
3003
800
1123
1576
2237
3053
4164
1122
1575
2237
3056
4238
5993
2234
3056
4242
6009
8275
11440
4211
6011
8434
11965
16231
22856
31638
743
1039
1415
2016
2817
3858
1030
1445
2027
2877
3925
5353
1444
2027
2879
3932
5452
7706
2877
3935
5461
7734
10648
14716
5425
7743
10863
15408
20897
29419
40712
307
430
586
836
1170
1605
425
597
838
1191
1628
2223
595
836
1188
1625
2256
3193
1184
1621
2251
3192
4400
6088
2229
3184
4469
6344
8611
12135
16809
Natural Gas
3"
1"
w.c.P w.c.P
432
605
824
1175
1644
2253
599
840
1180
1676
2288
3123
839
1178
1674
2287
3174
4491
1670
2285
3173
4497
6195
8568
3146
4493
6305
8947
12140
17101
23679
744
1041
1417
2019
2822
3865
1031
1447
2030
2881
3932
5362
1446
2030
2884
2938
5460
7719
2881
3941
5468
7746
10665
14741
5432
7754
10878
15429
20928
29466
40781
Notes:
6.
7.
8.
9.
10.
Orifice Bore Size Equals The Orifice Plate Inside Diameter. All Bore Sizes In Inches. Pipe Size Equals Schedule 40 Pipe.
Capacity Based On 60F @ 1 psig Upstream Pressure. Natural Gas Specific Gravity At 0.60; Air Specific Gravity At 1.0.
1__ Model Number Designates NPT Threaded Connection. 2__ Model Number Designates Weld-In Connection.
All Flow Rates At Standard Barometric Pressure: 29.92" Hg (Sea Level).
Design Capacity Is Based On 3" W.C.P.
5"
w.c.P
958
1339
1823
2597
3629
4967
1328
1863
2613
3707
5056
6894
1863
2614
3712
5068
7026
9929
3710
5075
7041
9971
13725
18966
6998
9988
14011
19870
26946
37931
52484