LIGHTNIN XDQ Series, Instructions Manual

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LIGHTNIN
REVISION DATE 2-1-85
LIGHTNIN £
¤
LIGHTNIN INST. NO. IT-850
F REVISED 1-2-07
MIXERS AND AERATORS
2007
PAGE 1 OF 1
BOLT TIGHTENING TORQUE RECOMMENDATIONS
Inadequately or improperly tightened hardware can loosen due to vibration or the load reactions imposed by fluid forces. This can result in reduced
equipment service life or damage and failure.
Recommended torques for tightening ANSI bolts and screws on
LIGHTNIN
Mixers and Aerators and their mounting structures are listed below for your
general reference. These average torque values should be considered only as guides and not as absolute values.
The amount of torque required to maintain a tight connection can vary considerably for bolts of the same size under different operating conditions.
Variations such as basic joint design, compression factors, type and strength of base and hardware material, surface finish of mating parts and
lubrication are only some of the factors that influence the tightness of bolted connections for given bolt torques.
UNLESS SPECIFICALLY LISTED ELSEWHERE IN THE DETAILED INSTRUCTIONS, TIGHTEN THE MIXER AND MOUNTING HARDWARE TO
THE RECOMMENDED VALUES SHOWN IN.
A torque wrench must be used to ensure compliance with these torque requirements.
Certain assembly connections may require special torques that are not listed in the table. These torques can be found in the detailed assembly and
disassembly sections of your manual. REVIEW YOUR MANUAL CAREFULLY TO DETERMINE WHERE SPECIAL TORQUES ARE REQUIRED.
For severe duty service, torques higher than listed, to tighten a bolt to maximum capacity, can often be used. However, due to the many variables
previously mentioned, the only absolute method to determine optimum torque is to deliberately yield a bolt under actual conditions. If a bolt does yield or
shear, 75% of the torque applied in yielding the bolt can be used to obtain a tight connection that is satisfactory.
ALL BOLTS SHOULD BE RETIGHTENED 12 HOURS AFTER ASSEMBLY, AND AT EACH SCHEDULED SHUT DOWN THEREAFTER.
RECOMMENDED TIGHTENING TORQUES FOR COMMERCIAL
GRADE STEEL, GR5, 304 AND 316 STAINLESS STEEL (1) (2)
BOLT
THREAD
SIZE
TIGHTENING TORQUES
(IN FT-LBS)
(4)
GRADE 2, 3 OR
304/316 SS BOLTS
LUBRICATED
TIGHTENING TORQUES
(IN FT-LBS)
(4)
GRADE 5
BOLTS
LUBRICATED
MARKING
GRADE
STEEL SAE GRADE
MARKING REFERENCE
GUIDE
(2)
1
/
4
_
20 4.6 7.2
5
/
16
_
18 9.6 15
3
/
8
_
16 17 26
NO MARK
SAE GRADES
0, 1 AND 2
7
/
16
_
14 27 42
1
/
2
_
20 41 64
9
/
16
_
12 60 92
SAE GRADE 3
5
/
8
_
11 83 128
3
/
4
_
10 146 226
7
/
8
_
9
(3)
142 365
SAE GRADE 5
1
_
8 212 547
1
1
/
8
_
7 301 675
1
1
/
4
_
7 425 952
ALL SOCKET
HEAD CAP SCREWS
SAE GRADE 5
1
3
/
8
_
6 557 1249
1
1
/
2
_
6 739 1657
1
3
/
4
_
5
(3)
754 1600
2
_
4
1
/
2
1134 2406
2
1
/
4
_
4
1
/
2
1659 3519
2
1
/
2
_
4 2269 4813
(1) ALL BOLTS SHOULD BE COATED WITH OIL, GREASE OR AN ANTI-SEIZE COMPOUND WHENEVER POSSIBLE. THE THREADS AND
BEARING FACE OF BOLT HEADS AND/OR NUTS SHOULD BE LUBRICATED.
(2) TORQUE VALUES SHOWN SUPERSEDE PREVIOUS TABLES THAT MAY HAVE ALLOWED LOWER VALUES. IT IS RECOMMENDED THAT
ONLY FASTENERS BE USED THAT ARE PROPERLY MARKED, INCLUDING MANUFACTURER’S TRADE MARKING. ONLY FASTENERS
MARKED AS SHOWN ARE GUARANTEED TO MEET SPECIFICATION AND PERFORMANCE REQUIREMENTS.
(3) ALLOWABLE BOLT STRESS VALUES CHANGE AT THESE LOCATIONS AND IS REFLECTED IN THE SUGGESTED TORQUE VALUES.
(4)
CONVERSION FACTORS:
FRICTION LOCKING DEVICES MULTIPLY LUBRICATED VALUE BY 1.15. THESE TORQUES PERTAIN TO BOLTS OR NUTS WITH FRICTION
LOCKING DEVICES SUCH AS NYLON PELLETS OR PATCHES, FIBER INSERTS OR UPSET THREADS.
DRY VALUES MULTIPLY LUBRICATED VALUE BY 1.33.
METRIC VALUES IN N-m 1FT-LB = 1.3558 N-m