Sunday, August 31, 2008
Serrated Washer | Safety Washer
Serrated Washer Safety Washer
ApplicationOutdoor or Indoor use. For use on cable gland entry threads.
FeaturesTo dampen vibrations of the cable gland/equipment assembly which may loosen the cable gland or locknut.
Materials & Finishes Hawke serrated washers are manufactured as standard in Stainless Steel.
Ordering ExamplesSerrated Washer/ThreadSerrated Washer/M25 Serrated Washer
FeaturesTo dampen vibrations of the cable gland/equipment assembly which may loosen the cable gland or locknut.
Materials & Finishes Hawke serrated washers are manufactured as standard in Stainless Steel.
Ordering ExamplesSerrated Washer/ThreadSerrated Washer/M25 Serrated Washer
Disc Spring Washer | Belleville Washer [Gear Used]
The mid-nineteenth century saw the conception of a conical shaped spring disc. This spring disc was subsequently termed a belleville washer after the name of its originator
Belleville WashersHeavy Duty Belleville Washers to DIN 6796
Phosphating : A zinc phosphate coating usually with subsequent oil or wax treatment. This treatment is widely offered as 'standard' on most stock-range carbon steel disc springs. The protection offered is sufficient to prevent corrosion throughout storage and normal transit conditions. It is adequate also for those applications where the disc springs are not directly exposed to the elements. However, where the application involves a more hostile environment, i.e. disc springs open to weather or marine conditions, chemical or acid laden atmosphere, etc; then a superior treatment or material must be considered.
Mechanical Zinc Plating : This is a method of depositing substantial thicknesses of zinc on the surfaces of disc springs without the risk of 'hydrogen embrittlement' associated with normal electro-plating. The zinc is impacted onto the surfaces by way of tumbling the disc springs in a rotating barrel, together with glass beads, metal powder, and promoting chemicals. In addition to removing the risk of embrittlement, the 'peening' aspect of this process is beneficial in terms of some stress relieving of the components. There are two forms of subsequent passivation treatment
TECHNICAL REQUIREMENTS:
Disc springs with bearing surfaces shall conform to group 3 din 2093
Disc spring stack consists of no of disc springs assembled in single series
Individual disc spring is to be tested with spring force P0.75 at disc height L0.75 and combined testing of the spring stack is to be done as per Spring diagram.
The test shall be done with the help of two pressure plates provided on both the sides which shall be harden ground and polished, using suitable lubricant.
Values encircled as shall be measured and recorded by supplier on test certificate values of and are for reference only.MANUFACTURING METHODS.5.1 Disc are to be manufactured by hot forming5.2 Disc are to be machined all over and sharp edges to be rounded off5.3 Concentricity of diameter should be within 0.5mm
HARDNESS SURFACE AND SCRAGGING.6.1 The decarburization of disc springs after heat treatment should not exceed 3% of disc thickness6.2 Hardness of each disc should be within 42 to52 HRC6.3 After heat treatment disc spring must be subjected to scragging, to ensure that after being loaded at twice the force P0.75 the free height of disc does not vary6.4 The surface must be free from defects viz crack, pits, rust, spots, etc.
Anti corrosive coating on disc springs can be Phosphatising, ZN OR CD plating as per suppliers choice.
Material test certificate should include chemical properties and hardness of disc springs.
Identification of springs as per HW 040397 at a places marked with the in identification marking should not dissolve in turbine oil and fire- resistant fluid (phosphate esters).
In addition each disc spring shall be marked with stack no and disc No. Disc No.2 of stack no 1 shall be marked as I/?.
Disc springs shall be property tied together and packed to avoid intermixing and damage during Transit and storing.
Spiral Washers
Spiral Washers
frames, MTS 601.11 Spiral Washers
can be used anywhere a backlashfree,
threaded union is required.
These versatile accessories prevent
backlash in threaded unions
during through-zero cyclic loading.
This is accomplished by preloading
the stud to a tensile force
slightly higher than the required
test load, then tightening the spiral
washers. When the preload is
removed, the stud remains in
tensile load and the components
in compressive load throughout
the test.
B E N E F I T S
Backlash-Free Joints
Use these spiral washers anywhere
you need a backlashfree
connection for throughzero
loading.
Protects Your Joints From
Fatigue
With these spiral washers, you
take the cyclic load out of the
stud.
Wide Temperature Range
Use from –200 to +350°F (–129
to +177°C).
O P T I O N S
Shims
For rotationally aligning your
fixture to your load frame:
0.004 in (0.10 mm) thick for
5 Kip (25 KN) spiral washers.
0.006 in (0.15 mm) thick for
22 Kip (100 KN) washers.
0.006 in (0.15 mm) thick for
55 Kip (250 KN) washers.
Spanner Wrenches
For adjusting spiral washers
(two required).
Specify spanner pin diameter
(see chart).
S P E C I F I C A T I O N S
Model Force Dimensions Spanner Part
Number Rating A B C Pin Dia. Number
601.11A-20 5.5 kip 1.62 in 0.82 in 1/2-20 0.19 in 40-473-119
601.11B-20 25 kN 41 mm 21 mm M12 x 1.25 4.8 mm 40-473-120
601.11A-11 22 kip 2.62 in 1 in 1-14 0.25 in 40-473-101
601.11B-11 100 kN 66 mm 25 mm M27 x 2 6.8 mm 40-473-110
601.11A-19 55 kip 3.62 in 1.25 in 11/2-12 0.25 in 40-473-102
601.11B-19 250 kN 92 mm 32 mm M36 x 2 6.8 mm 40-473-111
601.11A-13 110 kip 5.12 in 1.25 in 2-12 0.25 in 40-473-104
601.11B-13 500 kN 130 mm 32 mm M52 x 2 6.8 mm 40-473-113
601.11A-15 220 kip 7 in 1.75 in 3-12 0.38 in 40-473-106
601.11B-15 1000 kN 178 mm 44 mm M76 x 2 9.5 mm 40-473-115
spiral washers is much greater than
the cross-sectional area of the stud,
most of the fatigue loading during
testing is absorbed by the washers in
compression, rather than by the stud
in tension. As a result, these spiral
washers also extend the life of the
stud and the threads in your actuator,
load cell or other components.
MTS also provides shims, sold
separately, for rotational alignment
of your fixtures. These can be used
to reorient your fixtures if they no
longer face forward when the spiral
washers are tightened.
frames, MTS 601.11 Spiral Washers
can be used anywhere a backlashfree,
threaded union is required.
These versatile accessories prevent
backlash in threaded unions
during through-zero cyclic loading.
This is accomplished by preloading
the stud to a tensile force
slightly higher than the required
test load, then tightening the spiral
washers. When the preload is
removed, the stud remains in
tensile load and the components
in compressive load throughout
the test.
B E N E F I T S
Backlash-Free Joints
Use these spiral washers anywhere
you need a backlashfree
connection for throughzero
loading.
Protects Your Joints From
Fatigue
With these spiral washers, you
take the cyclic load out of the
stud.
Wide Temperature Range
Use from –200 to +350°F (–129
to +177°C).
O P T I O N S
Shims
For rotationally aligning your
fixture to your load frame:
0.004 in (0.10 mm) thick for
5 Kip (25 KN) spiral washers.
0.006 in (0.15 mm) thick for
22 Kip (100 KN) washers.
0.006 in (0.15 mm) thick for
55 Kip (250 KN) washers.
Spanner Wrenches
For adjusting spiral washers
(two required).
Specify spanner pin diameter
(see chart).
S P E C I F I C A T I O N S
Model Force Dimensions Spanner Part
Number Rating A B C Pin Dia. Number
601.11A-20 5.5 kip 1.62 in 0.82 in 1/2-20 0.19 in 40-473-119
601.11B-20 25 kN 41 mm 21 mm M12 x 1.25 4.8 mm 40-473-120
601.11A-11 22 kip 2.62 in 1 in 1-14 0.25 in 40-473-101
601.11B-11 100 kN 66 mm 25 mm M27 x 2 6.8 mm 40-473-110
601.11A-19 55 kip 3.62 in 1.25 in 11/2-12 0.25 in 40-473-102
601.11B-19 250 kN 92 mm 32 mm M36 x 2 6.8 mm 40-473-111
601.11A-13 110 kip 5.12 in 1.25 in 2-12 0.25 in 40-473-104
601.11B-13 500 kN 130 mm 32 mm M52 x 2 6.8 mm 40-473-113
601.11A-15 220 kip 7 in 1.75 in 3-12 0.38 in 40-473-106
601.11B-15 1000 kN 178 mm 44 mm M76 x 2 9.5 mm 40-473-115
spiral washers is much greater than
the cross-sectional area of the stud,
most of the fatigue loading during
testing is absorbed by the washers in
compression, rather than by the stud
in tension. As a result, these spiral
washers also extend the life of the
stud and the threads in your actuator,
load cell or other components.
MTS also provides shims, sold
separately, for rotational alignment
of your fixtures. These can be used
to reorient your fixtures if they no
longer face forward when the spiral
washers are tightened.
Saturday, August 30, 2008
Fastener Quality Act Information
Fastener Quality Act Information
This link to the National Institute of Standards homepage on the Fastener
Quality Act as an aide to individuals who need detailed and complete information on the
Act. Click here to have the most detailed information on the Fastener Ouality Act at your
fingertips.
Proper Tightening of Fasteners
Threaded fasteners are tightened for the obvious reason of clamping parts together and
transmitting loads. In gasketed joints, the purpose is to prevent leakage. In other joints,
the clamping force is developed to prevent the parts from separating or shaking loose.
The proper amount of tightening (or pre-load) is important. If the fasteners are too tight
they may break - either during the tightening itself or when the working load is added to
the pre-load in applications such as gasketed joints. If too loose, the fastener will shake
loose in vibration. Often overlooked, but equally important, is the tendency of fasteners
subjected to cyclic loading to fail from fatigue if not sufficiently tightened.
In normal joints, the clamping force should equal the working load. In gasketed joints, it
should be sufficient to create a seal.
EFFECT of FRICTION
When torque is applied to a fastener it (1) overcomes friction to turn the fastener and (2)
stretches the fastener - however slightly - to develop the clamping force. The latter is
considered the useful part of the torque.
It has been estimated that between 50% and 80% of the applied torque is needed to
overcome friction. As a result, failure will occur in the fastener before the axial strength,
determined by tensile testing the fastener, can be reached.
It is evident then, that the better the lubrication on the fastener the more of the torque
energy will be converted into actual clamping force.
The type of lubricant used has a definite effect on how much of the torque is needed to
overcome friction. Molybdenum disulfide, wax, and white lead are good lubricants;
cadmium and silver are fair, and machine oil is considered poor.
Published torque values are for average conditions. If the bolts are coated with a good
lubricant, threads help maintain a more consistent torque-tension relationship. Other
factors affecting friction are hardness of the material (generally, the harder it is, the less
friction) and type of material (aluminum is less "sticky" than steel but more so than cast
iron).
DETERMINATION of TORQUE
All fastener materials are slightly elastic and must be stretched a small amount to develop
clamping force. As a rule of thumb, a stretch of .001 inch per inch length of a fastener
develops about 30,000 psi clamping force in steel and 15,000 in titanium.
The best way to determine the correct torque is to run tests on the particular joint by
tightening five bolts until they just begin to yield. The optimum torque is 80% of this
value.
Another method is to tighten to 50% to 80% of the ultimate tensile strength on steel parts.
Pre-loading to 50% to 60% of the strength of the fastener is used because of the many
variables. The fastener should not be loaded above its torque yield strength, and the lower
values will generally keep the loads below this point. However, the more accurate the
method of controlling tightness the more of the strength of the fastener can be utilized.
This link to the National Institute of Standards homepage on the Fastener
Quality Act as an aide to individuals who need detailed and complete information on the
Act. Click here to have the most detailed information on the Fastener Ouality Act at your
fingertips.
Proper Tightening of Fasteners
Threaded fasteners are tightened for the obvious reason of clamping parts together and
transmitting loads. In gasketed joints, the purpose is to prevent leakage. In other joints,
the clamping force is developed to prevent the parts from separating or shaking loose.
The proper amount of tightening (or pre-load) is important. If the fasteners are too tight
they may break - either during the tightening itself or when the working load is added to
the pre-load in applications such as gasketed joints. If too loose, the fastener will shake
loose in vibration. Often overlooked, but equally important, is the tendency of fasteners
subjected to cyclic loading to fail from fatigue if not sufficiently tightened.
In normal joints, the clamping force should equal the working load. In gasketed joints, it
should be sufficient to create a seal.
EFFECT of FRICTION
When torque is applied to a fastener it (1) overcomes friction to turn the fastener and (2)
stretches the fastener - however slightly - to develop the clamping force. The latter is
considered the useful part of the torque.
It has been estimated that between 50% and 80% of the applied torque is needed to
overcome friction. As a result, failure will occur in the fastener before the axial strength,
determined by tensile testing the fastener, can be reached.
It is evident then, that the better the lubrication on the fastener the more of the torque
energy will be converted into actual clamping force.
The type of lubricant used has a definite effect on how much of the torque is needed to
overcome friction. Molybdenum disulfide, wax, and white lead are good lubricants;
cadmium and silver are fair, and machine oil is considered poor.
Published torque values are for average conditions. If the bolts are coated with a good
lubricant, threads help maintain a more consistent torque-tension relationship. Other
factors affecting friction are hardness of the material (generally, the harder it is, the less
friction) and type of material (aluminum is less "sticky" than steel but more so than cast
iron).
DETERMINATION of TORQUE
All fastener materials are slightly elastic and must be stretched a small amount to develop
clamping force. As a rule of thumb, a stretch of .001 inch per inch length of a fastener
develops about 30,000 psi clamping force in steel and 15,000 in titanium.
The best way to determine the correct torque is to run tests on the particular joint by
tightening five bolts until they just begin to yield. The optimum torque is 80% of this
value.
Another method is to tighten to 50% to 80% of the ultimate tensile strength on steel parts.
Pre-loading to 50% to 60% of the strength of the fastener is used because of the many
variables. The fastener should not be loaded above its torque yield strength, and the lower
values will generally keep the loads below this point. However, the more accurate the
method of controlling tightness the more of the strength of the fastener can be utilized.
Friday, August 29, 2008
Bolt Head Dimensions
Bolt Head Dimensions
The strength of a bolt is determined by its diameter and the strength of the material from which it is made. Minimum material strengths for various grades of bolts are given in a related page. Here, we deal with the diameter.
It may seem that the determination of a bolt's diameter is a simple matter of measurement, and this is indeed the case when the shank is exposed. In many cases, however, the shank is hidden, and the engineer who is charged with determining the strength of the bolted joint must infer the bolt's diameter from the size of its head. Fortunately, there are standards that govern the relationship between bolt size and head size. The following tables are based on information in
ANSI B18.2.1 (Square, Hex, and Heavy Hex)
ASTM A325 and A490 (High Strength Structural)
AISC Manual of Steel Construction (all)
Square Heads
D
F
C
H
1/4
3/8
1/2
3/16
3/8
9/16
13/16
1/4
1/2
3/4
1-1/16
5/16
5/8
15/16
1-5/16
7/16
3/4
1-1/8
1-9/16
1/2
7/8
1-5/16
1-7/8
5/8
1
1-1/2
2-1/8
11/16
1-1/8
1-11/16
2-3/8
3/4
1-1/4
1-7/8
2-5/8
7/8
1-3/8
2-1/16
2-15/16
15/16
1-1/2
2-1/4
3-3/16
1
All dimensions in inches
Hex Heads
D
F
C
H
1/4
7/16
1/2
3/16
3/8
9/16
5/8
1/4
1/2
3/4
7/8
3/8
5/8
15/16
1-1/16
7/16
3/4
1-1/8
1-5/16
1/2
7/8
1-5/16
1-1/2
9/16
1
1-1/2
1-3/4
11/16
1-1/8
1-11/16
1-15/16
3/4
1-1/4
1-7/8
2-3/16
7/8
1-3/8
2-1/16
2-3/8
15/16
1-1/2
2-1/4
2-5/8
1
1-3/4
2-5/8
3
1-3/16
2
3
3-7/16
1-3/8
2-1/4
3-3/8
3-7/8
1-1/2
2-1/2
3-3/4
4-5/16
1-11/16
2-3/4
4-1/8
4-3/4
1-13/16
3
4-1/2
5-3/16
2
3-1/4
4-7/8
5-5/8
2-3/16
3-1/2
5-1/4
6-1/16
2-5/16
3-3/4
5-5/8
6-1/2
2-1/2
4
6
6-15/16
2-11/16
All dimensions in inches
Heavy Hex Heads
D
F
C
H
1/2
7/8
1
3/8
5/8
1-1/16
1-1/4
7/16
3/4
1-1/4
1-7/16
1/2
7/8
1-7/16
1-11/16
9/16
1
1-5/8
1-7/8
11/16
1-1/8
1-13/16
2-1/16
3/4
1-1/4
2
2-5/16
7/8
1-3/8
2-3/16
2-1/2
15/16
1-1/2
2-3/8
2-3/4
1
1-3/4
2-3/4
3-3/16
1-3/16
2
3-1/8
3-5/8
1-3/8
2-1/4
3-1/2
4-1/16
1-1/2
2-1/2
3-7/8
4-1/2
1-11/16
2-3/4
4-1/4
4-15/16
1-13/16
3
4-5/8
5-5/16
2
All dimensions in inches
High Strength Structural Bolts
D
F
H
1/2
7/8
5/16
5/8
1-1/16
25/64
3/4
1-1/4
15/32
7/8
1-7/16
35/64
1
1-5/8
39/64
1-1/8
1-13/16
11/16
1-1/4
2
25/32
1-3/8
2-3/16
27/32
1-1/2
2-3/8
15/16
All dimensions in inches
The strength of a bolt is determined by its diameter and the strength of the material from which it is made. Minimum material strengths for various grades of bolts are given in a related page. Here, we deal with the diameter.
It may seem that the determination of a bolt's diameter is a simple matter of measurement, and this is indeed the case when the shank is exposed. In many cases, however, the shank is hidden, and the engineer who is charged with determining the strength of the bolted joint must infer the bolt's diameter from the size of its head. Fortunately, there are standards that govern the relationship between bolt size and head size. The following tables are based on information in
ANSI B18.2.1 (Square, Hex, and Heavy Hex)
ASTM A325 and A490 (High Strength Structural)
AISC Manual of Steel Construction (all)
Square Heads
D
F
C
H
1/4
3/8
1/2
3/16
3/8
9/16
13/16
1/4
1/2
3/4
1-1/16
5/16
5/8
15/16
1-5/16
7/16
3/4
1-1/8
1-9/16
1/2
7/8
1-5/16
1-7/8
5/8
1
1-1/2
2-1/8
11/16
1-1/8
1-11/16
2-3/8
3/4
1-1/4
1-7/8
2-5/8
7/8
1-3/8
2-1/16
2-15/16
15/16
1-1/2
2-1/4
3-3/16
1
All dimensions in inches
Hex Heads
D
F
C
H
1/4
7/16
1/2
3/16
3/8
9/16
5/8
1/4
1/2
3/4
7/8
3/8
5/8
15/16
1-1/16
7/16
3/4
1-1/8
1-5/16
1/2
7/8
1-5/16
1-1/2
9/16
1
1-1/2
1-3/4
11/16
1-1/8
1-11/16
1-15/16
3/4
1-1/4
1-7/8
2-3/16
7/8
1-3/8
2-1/16
2-3/8
15/16
1-1/2
2-1/4
2-5/8
1
1-3/4
2-5/8
3
1-3/16
2
3
3-7/16
1-3/8
2-1/4
3-3/8
3-7/8
1-1/2
2-1/2
3-3/4
4-5/16
1-11/16
2-3/4
4-1/8
4-3/4
1-13/16
3
4-1/2
5-3/16
2
3-1/4
4-7/8
5-5/8
2-3/16
3-1/2
5-1/4
6-1/16
2-5/16
3-3/4
5-5/8
6-1/2
2-1/2
4
6
6-15/16
2-11/16
All dimensions in inches
Heavy Hex Heads
D
F
C
H
1/2
7/8
1
3/8
5/8
1-1/16
1-1/4
7/16
3/4
1-1/4
1-7/16
1/2
7/8
1-7/16
1-11/16
9/16
1
1-5/8
1-7/8
11/16
1-1/8
1-13/16
2-1/16
3/4
1-1/4
2
2-5/16
7/8
1-3/8
2-3/16
2-1/2
15/16
1-1/2
2-3/8
2-3/4
1
1-3/4
2-3/4
3-3/16
1-3/16
2
3-1/8
3-5/8
1-3/8
2-1/4
3-1/2
4-1/16
1-1/2
2-1/2
3-7/8
4-1/2
1-11/16
2-3/4
4-1/4
4-15/16
1-13/16
3
4-5/8
5-5/16
2
All dimensions in inches
High Strength Structural Bolts
D
F
H
1/2
7/8
5/16
5/8
1-1/16
25/64
3/4
1-1/4
15/32
7/8
1-7/16
35/64
1
1-5/8
39/64
1-1/8
1-13/16
11/16
1-1/4
2
25/32
1-3/8
2-3/16
27/32
1-1/2
2-3/8
15/16
All dimensions in inches
Hex Head Bolt Markings
Hex Head Bolt Markings
The strength and type of steel used in a bolt is supposed to be indicated by a raised mark on the head of the bolt. The type of mark depends on the standard to which the bolt was manufactured. Most often, bolts used in machinery are made to SAE standard J429, and bolts used in structures are made to various ASTM standards. The tables below give the head markings and some of the most commonly-needed information concerning the bolts. For further information, see the appropriate standard.
The strength and type of steel used in a bolt is supposed to be indicated by a raised mark on the head of the bolt. The type of mark depends on the standard to which the bolt was manufactured. Most often, bolts used in machinery are made to SAE standard J429, and bolts used in structures are made to various ASTM standards. The tables below give the head markings and some of the most commonly-needed information concerning the bolts. For further information, see the appropriate standard.
SAE Bolt Designations
SAEGradeNo. Sizerange Tensile strength,ksi Material Head marking
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