C
INCH CATALOG
D
B
A
p e r f e c t i o n
i n
d e f l e c t i o n
Table of Contents
Letter from the President
3
Automation Locknuts
4,5
CollarPlus™ Locknuts
6
Flange Center Locknuts
7
TechPlus™ Locknuts
8
Finished Hex Center Locknuts
9
Jam and Machine Screw Top Locknuts
10
Acorn and Special Locknuts
11
Technical Information
12
Locknut Specifications
16
13
Locknut Applications
16
14
16
2
Letter from the President
From Aztech’s inception, quality has been our consistent theme. We have engineered
quality into every facet of the company’s work. We think quality products and productivity go hand in hand, so we build solid relationships with our customers by always striving
to be your partner in productivity.
True partnerships are not built overnight, but take time to develop. At Aztech, we believe
that trust, commitment and an understanding of your individual needs are the foundation blocks to building a lasting and mutually beneficial relationship.
One of the great resources Aztech offers is being a single source for all your locknut
and freespinning nut needs, from basic standards to fully custom designs. We reduce
the time required to purchase and inspect nuts and locknuts. Your Aztech team stands
ready to serve your every need with the broadest selection of quality nuts and attentive
personal service.
Let us deliver Perfection In Deflection... to you.
Mark Kaindl
President
Aztech Locknut Company
All sales by Aztech Locknut Company are made pursuant to the terms and conditions in effect during the time of delivery. Aztech Locknut Company shall not be held liable to the buyer or anyone else for any defect in goods that results in
personal injury, death, property damage, loss of use or replacement costs. Remedies to buyer under these circumstances is
provided at the discretion of Aztech Locknut Company.
3
Automation Locknuts
The top thread section of the Automation Locknut is precisely
displaced at two 180° opposing areas. This deflection ovalizes the
top threads of the nut and bends these threads out of their helical
configuration. This locking element remains springlike through
repeated applications and severe shock loads.
The Automation Locknut starts freely on a bolt or stud like a common
nut until the deflected thread portion is reached. It then requires
wrenching to a final position anywhere on the mating part. The
pronounced chamfer on the top of the nut makes it easily sorted
by sight, feel or selective devices and it is clearly visible that the end
product is safe-guarded by a locknut.
GRADE C
W
The Automation Locknut is precision manufactured on cold and hot
forming equipment to ensure uniform bearing area and a chamfered
top, thereby giving consistent prevailing torque results.
SIZE
Grade C
Automation Locknut, Grade C, Cadmium Plated *
SIZE
T
PART NUMBER
1/4-20
1/4-28
5/16-18
5/16-24
3/8-16
3/8-24
7/16-14
7/16-20
1/2-13
1/2-20
9/16-12
9/16-18
5/8-11
5/8-18
3/4-10
3/4-16
7/8-9
7/8-14
1-8
1-14
25CALNCC
25FALNCC
31CALNCC
31FALNCC
37CALNCC
37FALNCC
43CALNCC
43FALNCC
50CALNCC
50FALNCC
56CALNCC
56FALNCC
62CALNCC
62FALNCC
75CALNCC
75FALNCC
87CALNCC
87FALNCC
100CALNCC
100FALNCC
W
WIDTH ACROSS FLATS
MAX
MIN
.438
.438
.500
.500
.562
.562
.688
.688
.750
.750
.875
.875
.938
.938
1.125
1.125
1.312
1.312
1.500
1.500
.428
.428
.489
.489
.551
.551
.675
.675
.736
.736
.861
.861
.922
.922
1.088
1.088
1.269
1.269
1.450
1.450
T
THICKNESS
MAX
MIN
.226
.226
.273
.273
.337
.337
.385
.385
.448
.448
.496
.496
.559
.559
.665
.665
.776
.776
.887
.887
.212
.212
.258
.258
.320
.320
.365
.365
.427
.427
.473
.473
.535
.535
.617
.617
.724
.724
.831
.831
MEETS MIL. SPEC. 51943
* COMMON PARTS CHARTED, OTHER FINISHES AND MATERIALS AVAILABLE.
4
WEIGHT/
1000 PCS.
STEEL
6.7
6.7
9.8
9.8
14.5
14.5
25.0
25.0
34.8
34.8
53.7
53.7
70.2
70.2
120.0
120.0
207.0
207.0
260.0
260.0
Advantages
Fully Reusable - multiple times without appreciable loss in
locking torque.
Rugged - all-metal, one-piece construction withstands severe
vibration and shock loads common in equipment and vehicles.
Lock on Top - allows nut to be quickly threaded almost all the
way on the bolt before wrenching is required.
Spring Action of Lock - permits locking efficiency over the entire
range of bolt thread tolerances.
GRADE A
Grade A•B
W
SIZE
Automation Locknut, Grade A, Zinc Plated *
GRADE B
SIZE
PART NUMBER
1/4-20
5/16-18
3/8-16
7/16-14
1/2-13
T
W
SIZE
25CALNAZ
31CALNAZ
37CALNAZ
43CALNAZ
50CALNAZ
W
WIDTH ACROSS FLATS
MAX
MIN
.438
.500
.562
.688
.750
.428
.489
.551
.675
.736
T
THICKNESS
MAX
MIN
.226
.273
.337
.385
.448
WEIGHT/
1000 PCS.
STEEL
.212
.258
.320
.365
.427
6.7
9.8
14.5
25.0
34.8
*COMMON PARTS CHARTED, OTHER FINISHES AND MATERIALS AVAILABLE.
FINE THREADS AND LARGER DIAMETERS OFFERED AS TECH LOCK™ NUT, PAGE 11.
Automation Locknut, Grade B, Zinc Plated *
SIZE
T
PART NUMBER
W
WIDTH ACROSS FLATS
MAX
MIN
T
THICKNESS
MAX
MIN
WEIGHT/
1000 PCS.
STEEL
1/4-20
1/4-28
25CALNBZ
25FALNBZ
.438
.438
.428
.428
.257
.257
.243
.243
8.0
8.0
5/16-18
5/16-24
3/8-16
31CALNBZ
31FALNBZ
37CALNBZ
.500
.500
.562
.489
.489
.551
.302
.302
.377
.292
.292
.360
10.8
10.8
16.0
3/8-24
7/16-14
7/16-20
37FALNBZ
43CALNBZ
43FALNBZ
.562
.688
.688
.551
.675
.675
.377
.430
.430
.360
.410
.410
16.0
29.8
29.8
1/2-13
1/2-20
50CALNBZ
50FALNBZ
.750
.750
.736
.736
.510
.510
.490
.490
38.5
38.5
9/16-12
9/16-18
5/8-11
56CALNBZ
56FALNBZ
62CALNBZ
.875
.875
.938
.861
.861
.922
.555
.555
.645
.535
.535
.621
58.5
58.5
78.9
5/8-18
3/4-10
3/4-16
62FALNBZ
75CALNBZ
75FALNBZ
.938
1.125
1.125
.922
1.088
1.088
.645
.750
.750
.621
.702
.702
78.9
120.0
120.0
7/8-9
7/8-14
1-8
1-14
87CALNBZ
87FALNBZ
100CALNBZ
100FALNBZ
1.312
1.312
1.500
1.500
1.269
1.269
1.450
1.450
.862
.862
.958
.958
.810
.810
.902
.902
231.6
231.6
278.0
278.0
MEETS MIL. SPEC. 51922 (WHEN CAD PLATED)
*COMMON PARTS CHARTED, OTHER FINISHES AND MATERIALS AVAILABLE.
5
CollarPlus™ Locknuts
By ovalizing a precision manufactured collar at two 180° opposing
points, a spring-like locking element is developed. The collar locknut
retains consistent locking torque through repeated applications. By
deflecting the thinner top wall of the nut, the nut body and bottom
threads remain unaffected by the locking process. The collar locknut
starts freely on a bolt or stud until the locking element is reached, it
then requires torquing to its final position.
Collar locknuts have proven to be most effective when used in
applications requiring large diameters, high strength and light weight.
GRADE C COLLARPLUS
Grade C
Full CollarPlus Locknut, Grade C, Cadmium Plated *
SIZE
W
WIDTH ACROSS FLATS
MAX
MIN
T
THICKNESS
MAX
MIN
112CFROCC
1.687
1.631
0.999
0.939
353.8
112FFROCC
125CFROCC
1.687
1.875
1.631
1.812
0.999
1.094
0.939
1.030
346.1
480.0
125FFROCC
137CFROCC
1.875
2.062
1.812
1.994
1.094
1.206
1.030
1.138
470.0
671.4
137FFROCC
150CFROCC
2.062
2.250
1.994
2.175
1.206
1.317
1.138
1.245
675.1
820.0
150FFROCC
175CFROCC
2.250
2.625
2.175
2.538
1.317
1.540
1.245
1.460
800.0
1400.0
PART NUMBER
11/8-7
11/8-12
11/4-7
11/4-12
13/8-6
13/8-12
11/2-6
11/2-12
13/4-5
13/4-12
2-41/2
2-12
21/4-41/2
21/4-12
21/2-4
21/2-12
3-4
3-12
WEIGHT/
1000 PCS.
STEEL
175FFROCC
2.625
2.538
1.540
1.460
1314.3
200CFROCC
200FFROCC
225CFROCC
225FFROCC
3.000
3.000
3.375
3.375
2.900
2.900
3.275
3.275
1.763
1.763
2.016
2.016
1.675
1.675
1.920
1.920
2050.0
1950.0
2850.0
2750.0
250CFROCC
250FFROCC
300CFROCC
300FFROCC
3.750
3.750
4.500
4.500
3.620
3.620
4.350
4.350
2.239
2.239
2.685
2.685
2.135
2.135
2.565
2.565
3910.0
3800.0
6650.0
6460.0
Thin CollarPlus Locknut, Grade C, Cadmium Plated *
11/8-7
11/8-12
11/4-7
11/4-12
13/8-6
13/8-12
11/2-6
11/2-12
112CTROCC
112FTROCC
1.687
1.687
1.631
1.631
0.639
0.639
0.579
0.579
230.0
225.0
125CTROCC
125FTROCC
1.875
1.875
1.812
1.812
0.751
0.751
0.687
0.687
332.0
332.0
137CTROCC
137FTROCC
2.062
2.062
1.994
1.994
0.815
0.815
0.747
0.747
415.0
400.0
150CTROCC
2.250
2.175
0.880
0.808
566.6
150FTROCC
2.250
2.175
0.880
0.808
544.4
*COMMON PARTS CHARTED, OTHER FINISHES AND MATERIALS AVAILABLE.
6
Flange Center Locknuts
Flange Locknuts offer additional bearing surface for use on elongated
holes of slots and when assembling soft materials. The additional
bearing surface helps distribute the clamp load over a greater area.
Use of a flange locknut eliminates the need for a washer, thereby allowing for faster assembly and fewer fastener parts in the assembly.
Both the flange center lock and flange Tech Lock™ provide a secure
locking element created by deflected nut threads at two opposing
positions on the nut body.
FLANGE CENTER LOCKNUT GRADE F
It is not necessary for the mating part to fully protrude from the top of
the flange center lock nut. The flange Tech locknut does require that
the mating part protrude a sufficient length to fully engage the locking
element. The flange Tech locknuts represent a lower cost and lighter
weight alternative to the flange cone locknuts.
Flange Center Locknut, Grade F, Zinc Plated*
LARGE FLANGE CENTER LOCKNUT
GRADE F
D
W
SIZE
T
W
WIDTH ACROSS FLATS
MAX
MIN
T
THICKNESS
MAX
MIN
D
WEIGHT/
1000 PCS.
STEEL
SIZE
PART NUMBER
1/4-20
1/4-28
5/16-18
5/16-24
3/8-16
3/8-24
7/16-14
7/16-20
1/2-13
1/2-20
9/16-12
25CRFCFZ
25FRFCFZ
31CRFCFZ
31FRFCFZ
37CRFCFZ
37FRFCFZ
43CRFCFZ
43FRFCFZ
50CRFCFZ
50FRFCFZ
56CRFCFZ
.438
.438
.500
.500
.562
.562
.688
.688
.750
.750
.875
.428
.428
.489
.489
.551
.551
.675
.675
.736
.736
.861
.236
.236
.283
.283
.347
.347
.395
.395
.458
.458
.506
.222
.222
.268
.268
.330
.330
.375
.375
.437
.437
.483
.560
.560
.680
.680
.810
.810
.930
.930
1.070
1.070
1.190
.474
.474
.602
.602
.730
.730
.846
.846
.982
.982
1.101
9.0
9.0
12.3
12.3
17.8
17.8
34.5
34.5
44.0
44.0
65.0
9/16-18
5/8-11
5/8-18
3/4-10
3/4-16
7/8-9
7/8-14
1-8
1-14
56FRFCFZ
62CRFCFZ
62FRFCFZ
75CRFCFZ
75FRFCFZ
87CRFCFZ
87FRFCFZ
100CRFCFZ
100FRFCFZ
.875
.938
.938
1.125
1.125
1.312
1.312
1.500
1.500
.861
.922
.922
1.068
1.068
1.269
1.269
1.450
1.450
.506
.569
.569
.675
.675
.787
.787
.900
.900
.483
.545
.545
.627
.627
.737
.737
.850
.850
1.190
1.330
1.330
1.585
1.585
1.750
1.750
2.060
2.060
1.101
1.230
1.230
1.472
1.472
1.667
1.667
1.970
1.970
65.0
72.0
72.0
136.0
136.0
215.0
215.0
318.0
318.0
FLANGE
DIA. MAX
BEARING
DIA. MIN
Large Flange Center Locknut, Grade F, Zinc Plated*
SIZE
PART NUMBER
1/4-20
5/16-18
3/8-16
1/2-13
25CLFCFZ
31CLFCFZ
37CLFCFZ
50CLFCFZ
W
WIDTH ACROSS FLATS
MAX
MIN
.438
.500
.562
.750
.428
.489
.551
.736
T
THICKNESS
MAX
MIN
.312
.375
.406
.515
FLANGE
DIA. MAX
.281
.343
.390
.485
D
BEARING
DIA. MIN
.728
.820
.915
1.205
.700
.790
.885
1.175
WEIGHT/
1000 PCS.
STEEL
11.8
22.5
28.2
55.0
Super Flange Center Locknut Grade F, Zinc Plated*
SIZE
1/4-20
5/16-18
3/8-16
PART NUMBER
25CSFCFZ
31CSFCFZ
37CSFCFZ
W
WIDTH ACROSS FLATS
MAX
MIN
.500
.562
.687
.488
.546
.669
T
THICKNESS
MAX
MIN
.312
.375
.406
FLANGE
DIA. MAX
.281
.343
.390
.906
.968
1.093
D
BEARING
DIA. MIN
.812
.875
1.000
WEIGHT/
1000 PCS.
STEEL
19.0
27.5
45.5
* COMMON PARTS CHARTED, OTHER FINISHES AND MATERIALS AVAILABLE.
7
TechPlus™ Locknuts
Flange TechPlus Locknut, Grade F, Zinc Plated* (#8-5/16” Punch Lock)
SIZE
TechPlus Grade F
D
W
PART NUMBER
W
WIDTH ACROSS FLATS
MAX
MIN
T
THICKNESS
MAX
MIN
FLANGE
DIA. MAX
D
BEARING
DIA. MIN
WEIGHT/
1000 PCS.
STEEL
8-32
10-24
8CRFOFZ
10CRFOFZ
.344
.375
.334
.365
.203
.219
.187
.203
.469
.500
.415
.442
5.2
6.0
10-32
12-24
10FRFOFZ
12CRFOFZ
.375
.438
.365
.428
.219
.234
.203
.223
.500
.594
.442
.484
6.0
9.0
1/4-20
1/4-28
25CRFOFZ
25FRFOFZ
.438
.438
.428
.428
.236
.236
.222
.222
.560
.560
.484
.484
9.0
9.0
5/16-18
31CRFOFZ
.500
.489
.283
.268
.680
.602
12.3
5/16-24
3/8-16
3/8-24
31FRFOFZ
37CRFOFZ
37FRFOFZ
.500
.562
.562
.489
.551
.551
.283
.347
.347
.268
.330
.330
.680
.810
.810
.602
.730
.730
12.3
17.8
17.8
7/16-14
43CRFOFZ
.688
.675
.395
.375
.930
.846
34.5
7/16-20
1/2-13
1/2-20
43FRFOFZ
50CRFOFZ
50FRFOFZ
.688
.750
.750
.675
.736
.736
.395
.458
.458
.375
.437
.437
.930
1.070
1.070
.846
.982
.982
34.5
44.0
44.0
9/16-12
9/16-18
5/8-11
56CRFOFZ
56FRFOFZ
62CRFOFZ
.875
.875
.938
.861
.861
.922
.506
.506
.569
.483
.483
.545
1.190
1.190
1.330
1.101
1.101
1.230
65.0
65.0
72.0
5/8-18
3/4-10
62FRFOFZ
75CRFOFZ
.938
1.125
.922
1.088
.569
.675
.545
.627
1.330
1.585
1.230
1.472
72.0
136.0
3/4-16
7/8-9
75FRFOFZ
87CRFOFZ
1.125
1.312
1.088
1.269
.675
.787
.627
.737
1.585
1.750
1.472
1.667
136.0
215.0
7/8-14
1-8
87FRFOFZ
100CRFOFZ
1.312
1.500
1.269
1.450
1-14
100FRFOFZ
1.500
.787
.900
.900
.737
.850
.850
1.750
2.060
2.060
1.667
1.970
1.970
215.0
318.0
318.0
1.450
Large Flange TechPlus Locknut, Grade F
SIZE
1/4-20
5/16-18
3/8-16
1/2-13
PART NUMBER
25CLFOFZ
31CLFOFZ
37CLFOFZ
50CLFOFZ
W
WIDTH ACROSS FLATS
MAX
MIN
.438
.500
.562
.750
.428
.489
.551
.736
T
THICKNESS
MAX
MIN
.312
.375
.406
.515
.281
.343
.390
.485
FLANGE
DIA. MAX
D
BEARING
DIA. MIN
.728
.820
.915
1.205
.700
.790
.885
1.175
WEIGHT/
1000 PCS.
STEEL
11.8
22.5
28.2
55.0
Super Flange TechPlus Locknut, Grade F, Zinc Plated*
SIZE
T
SIZE
1/4-20
5/16-18
3/8-16
PART NUMBER
25CSFOFZ
31CSFOFZ
37CSFOFZ
W
WIDTH ACROSS FLATS
MAX
MIN
.500
.562
.687
.488
.546
.669
T
THICKNESS
MAX
MIN
.312
.375
.406
.281
.343
.390
FLANGE
DIA. MAX
D
BEARING
DIA. MIN
.906
.968
1.093
.812
.875
1.000
WEIGHT/
1000 PCS.
STEEL
19.0
27.5
45.5
Flange TechPlus Locknut, Grade G, Cadmium Plated*
SIZE
PART NUMBER
5/16-18
3/8-16
3/8-24
7/16-14
7/16-20
1/2-13
1/2-20
9/16-12
9/16-18
5/8-11
5/8-18
3/4-10
3/4-16
7/8-9
7/8-14
1-8
1-14
31CRFOGC
37CRFOGC
37FRFOGC
43CRFOGC
43FRFOGC
50CRFOGC
50FRFOGC
56CRFOGC
56FRFOGC
62CRFOGC
62FRFOGC
75CRFOGC
75FRFOGC
87CRFOGC
87FRFOGC
100CRFOGC
100FRFOGC
W
WIDTH ACROSS FLATS
MAX
MIN
.500
.565
.565
.687
.687
.750
.750
.875
.875
.939
.939
1.125
1.125
1.312
1.312
1.500
1.500
.489
.551
.551
.675
.675
.736
.736
.861
.861
.922
.922
1.088
1.088
1.269
1.269
1.450
1.450
T
THICKNESS
MAX
MIN
.338
.385
.385
.450
.450
.510
.510
.560
.560
.605
.605
.742
.742
.787
.787
.900
.900
.318
.365
.365
.430
.430
.490
.490
.530
.530
.581
.581
.715
.715
.737
.737
.850
.850
FLANGE
DIA. MAX
.680
.810
.810
.930
.930
1.070
1.070
1.190
1.190
1.330
1.330
1.585
1.585
1.750
1.750
2.060
2.060
* COMMON PARTS CHARTED, OTHER FINISHES AND MATERIALS AVAILABLE.
* NONSTANDARD ITEM. CALL FOR STOCK STATUS.
8
D
BEARING
DIA. MIN
.602
.730
.730
.846
.846
.982
.982
1.101
1.101
1.230
1.230
1.472
1.472
1.667
1.667
1.970
1.970
WEIGHT/
1000 PCS.
STEEL
14.7
21.6
21.6
41.4
41.4
52.8
52.8
65.0
65.0
90.0
90.0
168.0
168.0
215.0
215.0
318.0
318.0
Finished Hex Center Locknuts
The centermost threads of the Center Locknut have been precision
deflected at two 180° opposing pressure points, therefore uniformly
ovalizing the nut and bending the center threads of the nut out of
their true helix.
The locking element spreads over several of the center threads,
engaging the mating threads of a bolt or stud with a resilient 180°
spring lock.
GRADE A WITH
STANDARD 3-HIT
DEFLECTION
Whatever bearing face is selected as top or bottom, the Center
Locknut starts freely. When the locking element threads in the center
of the nut are reached, the nut must be wrenched to its final position.
This can be any place on the bolt as seating is not required for locking
effectiveness.
OPTIONAL 2-HIT
DEFLECTION AVAILABLE
ON GRADE A AND
GRADE B MATERIAL
W
It is not necessary for the bolt to extend out of a Center Locknut.
Before the bolt end reaches the top of the nut, the lock is fully
engaged. This factor is important when the space above the nut is
limited and when the weight of the final assembly is a critical factor. It
also allows the use of shorter bolts.
Center Locknuts are most appropriate when they are to be machine
applied. Since the top and bottom are identical, selective feeding
devices are not required. This feature also simplifies hand assembly.
SIZE
GRADE B WITH GRADE
IDENTIFICATION
MARK STANDARD 2-PT
DEFLECTION
Finished Hex Center Locknut, Zinc Plated*
SIZE
T
ADVANTAGES
Fully Reusable - multiple times without appreciable
loss in locking torque.
Rugged - all-metal, one-piece construction
withstands severe vibration and shock loads.
Spring Action of Lock - permits locking efficiency
over the entire range of bolt thread tolerances.
PART NUMBER
8-32
10-24
10-32
1/4-20
1/4-28
5/16-18
5/16-24
3/8-16
3/8-24
7/16-14
7/16-20
1/2-13
1/2-20
9/16-12
9/16-18
5/8-11
5/8-18
3/4-10
3/4-16
7/8-9
7/8-14
1-8
1-14
8CFHCAZ
10CFHCAZ
10FFHCAZ
25CFHCAZ
25FFHCAZ
31CFHCAZ
31FFHCAZ
37CFHCAZ
37FFHCAZ
43CFHCAZ
43FFHCAZ
50CFHCAZ
50FFHCAZ
56CFHCAZ
56FFHCAZ
62CFHCAZ
62FFHCAZ
75CFHCAZ
75FFHCAZ
87CFHCAZ
87FFHCAZ
100CFHCAZ
100FFHCAZ
W
WIDTH ACROSS FLATS
MAX
MIN
T
THICKNESS
MAX
MIN
.344
.375
.375
.438
.438
.500
.500
.562
.562
.688
.688
.750
.750
.875
.875
.938
.938
1.125
1.125
1.312
1.312
1.500
1.500
.193
.203
.203
.226
.226
.273
.273
.337
.337
.385
.385
.448
.448
.496
.496
.559
.559
.665
.665
.776
.776
.887
.887
.332
.362
.362
.428
.428
.489
.489
.551
.551
.675
.675
.736
.736
.861
.861
.922
.922
1.088
1.088
1.269
1.269
1.450
1.450
.178
.187
.187
.212
.212
.258
.258
.320
.320
.365
.365
.427
.427
.473
.473
.535
.535
.617
.617
.724
.724
.831
.831
WEIGHT/
1000 PCS.
STEEL
4.0
5.0
5.0
7.35
7.35
11.0
11.0
16.0
16.0
28.4
28.4
37.5
37.5
58.3
58.3
73.3
73.3
119
119
190
190
283
283
* COMMON PARTS CHARTED, OTHER FINISHES AND MATERIALS AVAILABLE.
9
Jam Locknuts
The low profile of the jam nut pattern provides the design engineer
with another locknut option in the full range of diameters. Center
and toplock choices increase the variety. Superior 3-point deflection
for center lock jam insures easier assembly with some free rotation
before engaging the locking element.
Standard Jam Top Locknut, Zinc Plated*
TOP LOCK
SIZE
T
3-POINT CENTER LOCK
W
PART NUMBER
W
WIDTH ACROSS FLATS
MAX
MIN
T
THICKNESS
MAX
MIN
WEIGHT/
1000 PCS.
STEEL
1/4-20
25CFJPAZ
.438
.428
.164
.150
5.1
1/4-28
5/16-18
25FFJPAZ
31CFJPAZ
.438
.500
.428
.489
.164
.195
.150
.180
5.1
7.6
5/16-24
3/8-16
3/8-24
7/16-14
7/16-20
1/2-13
1/2-20
9/16-12
31FFJPAZ
37CFJPAZ
37FFJPAZ
43CFJPAZ
43FFJPAZ
50CFJPAZ
50FFJPAZ
56CFJPAZ
.500
.562
.562
.688
.688
.750
.750
.875
.489
.551
.551
.675
.675
.736
.736
.861
.195
.227
.227
.260
.260
.323
.323
.324
.180
.210
.210
.240
.240
.302
.302
.301
7.6
10.5
10.5
18.6
18.6
26.2
26.2
36.8
9/16-18
5/8-11
56FFJPAZ
62CFJPAZ
.875
.938
.861
.922
.324
.387
.301
.363
36.8
49.3
5/8-18
3/4-10
62FFJPAZ
75CFJPAZ
.938
1.125
.922
1.088
.387
.446
.363
.398
49.3
77.0
3/4-16
7/8-9
75FFJPAZ
87CFJPAZ
1.125
1.312
1.088
1.269
.446
.510
.398
.458
77.0
120.0
7/8-14
1-8
87FFJPAZ
100CFJPAZ
1.312
1.500
1.269
1.450
.510
.575
.458
.519
120.0
176.0
1-14
100FFJPAZ
1.500
1.450
.575
.519
176.0
LARGER SIZES AVAILABLE
* COMMON PARTS CHARTED, OTHER FINISHES AND MATERIALS AVAILABLE.
SIZE
Machine
Screw Top Locknuts
HEX MACHINE SCREW TOP
LOCKNUT
Aztech excels at small pattern locknut manufacturing producing
consistent installation torques for many electronics applications. This
style satisfies low profile top locknut requirements.
Hex Machine Screw Top Locknut, Zinc Plated*
SIZE
4-40
5-32
6-32
8-32
10-24
10-32
12-24
12-28
1/4-20
1/4-28
5/16-18
5/16-24
3/8-16
3/8-24
PART NUMBER
4CMHPAZ
5CMHPAZ
6CMHPAZ
8CMHPAZ
10CMHPAZ
10FMHPAZ
12CMHPAZ
12FMHPAZ
25CMHPAZ
25FMHPAZ
31CMHPAZ
31FMHPAZ
37CMHPAZ
37FMHPAZ
W
WIDTH ACROSS FLATS
MAX
MIN
.250
.312
.312
.344
.375
.375
.438
.438
.438
.438
.562
.562
.625
.625
.241
.302
.302
.332
.362
.362
.423
.423
.423
.423
.545
.545
.607
.607
T
THICKNESS
MAX
MIN
.098
.114
.114
.130
.130
.130
.161
.161
.193
.193
.225
.225
.257
.257
.087
.102
.102
.117
.117
.117
.148
.148
.178
.178
.208
.208
.239
.239
* COMMON PARTS CHARTED, OTHER FINISHES AND MATERIALS AVAILABLE.
10
WEIGHT/
1000 PCS.
STEEL
1.1
2.0
2.1
2.8
3.3
3.3
5.6
5.6
6.1
6.1
12.1
12.1
15.8
15.8
Acorn Center Locknuts
The precision center lock deflection is located on opposite sides of
the acorn nut body. Accurately located on the nut flats, the center lock
fully engages the mating bolt before it protrudes past the hex flats.
These features allow a reliable locking assembly for a decorative or
snag free application.
HIGH CROWN
ACORN CENTER
LOCKNUT
SIZE
Standard Acorn Center Locknut, Zinc Plated*
W
LOW CROWN
ACORN CENTER
LOCKNUT
SIZE
W
T
T
SIZE
PART NUMBER
W
WIDTH ACROSS FLATS
MAX
MIN
T
THICKNESS
MAX
MIN
WEIGHT/
1000 PCS.
STEEL
HIGH CROWN
10-24
1/4-20
5/16-18
3/8-16
1/2-13
.375
.437
.500
.562
.750
.362
.428
.489
.551
.736
.525
.603
.697
.791
1.033
.505
.583
.677
.771
.995
10.4
14.3
20.3
28.0
78.0
6-32
8-32
10-24
1/4-20
10CHCCAZ
25CHCCAZ
31CHCCAZ
37CHCCAZ
50CHCCAZ
LOW CROWN
6CLCCAZ
8CLCCAZ
10CLCCAZ
25CLCCAZ
.312
.344
.375
.437
.302
.332
.362
.428
.350
.350
.416
.478
.338
.338
.396
.458
4.6
5.4
8.4
11.5
5/16-18
3/8-16
31CLCCAZ
37CLCCAZ
.500
.562
.489
.551
.541
.635
.521
.615
16.3
22.8
1/2-13
50CLCCAZ
.750
.736
.818
.805
51.0
ACORN NUTS ARE ALSO AVAILABLE IN FINE THREAD AND STAINLESS OR
BRASS MATERIALS.
*COMMON PARTS CHARTED, OTHER FINISHES AND MATERIALS AVAILABLE.
Aztech can offer a variety of special locknut configurations including,
but not limited to, the items pictured here. Our expertise at thread
deflection can benefit the engineer with a special design in mind.
Special Locknuts
Because our locking machines are right here at
our Aurora, IL manufacturing facility, we have
the capabilities to offer a wide variety of locking
styles and prevailing torque ranges! Have a special
engineering requirement calling for a lighter or
heavier installation torque or a particular locking
configuration? Let us know, our tool room and locking
machines are on site and our Sales, Engineering
and Production departments can match up your
customer’s needs with our expertise!
Other standard product lines include metric
locknuts, free spinning locknuts, weld nuts (free
spinning and locked), nylon patch and others.
Call for literature.
11
Technical Information
Torque Measuring Device - A torque wrench accurate to within
plus or minus 2% of the maximum. All readings must fall within
the upper 50% of the wrench selected.
Load Measuring Device - A calibrated load measuring device
(Skidmore Wilhelm) accurate to within plus or minus 5%. The
Device is fitted with attachments to accept the bolt and nut to be
tested.
Hardened Mandrel - A post threaded to Class 3A fit, except that
the major diameter shall be the minimum major diameter with a
plus tolerance of .002. Mandrel hardness shall be RC45-50.
Test Bolt - The test bolt has an ultimate tensile strength that
exceeds the proof load of the nuts tested. The bolts meet class 2A
tolerance and are zinc phosphate plated to meet a 72 hour salt
spray with an oil finish dry to the touch. Bolt thread length is such
that when assembled in the load cell, a minimum of two thread
pitches remain below the nut and six protrude through it. The bolt
is to be free of burrs and contaminants.
Prevailing Torque Test/Torque Tension Test - The prevailing
torque test is conducted at room temperature to the applicable
grade and thread specifications.
At no time during these four additional installations and removals
should the torque exceed the maximum “first installation.” During
the first 360° of the fifth removal, the torque values will fluctuate
between a highest and lowest reading on the wrench scale. The
highest value must meet or exceed the fifth removal “highest
reading minimum.” The lowest value must meet or exceed the
fifth removal ”lowest reading minimum.”
Proof Load Test - A test sample nut is assembled on a hardened
mandrel mounted in a load measuring device. The maximum
prevailing torque occurring during assembly is recorded. A load
equal to the proof load specified for the grade and thread pitch
of the sample nut is applied in tension. The nut must resist this
load without thread stripping or rupture. The prevailing torque
necessary to remove the nut from the mandrel shall not exceed
the maximum torque occurring during the assembly.
Hardness Test - The Rockwell hardness of a sample nut is
determined on the top face of the nut to provide a flat area
between the hex corner and the major diameter of the thread.
The hardness test is performed in the center of this area once any
plating or coating is ground from the bearing surface (bottom) of
the nut.
GRADE
A test bolt is inserted into a load measuring device fitted for the
size tested. A hardened washer is assembled on the bolt and
is prevented from turning throughout the procedure. The nut
tested is advanced on the bolt until two threads protrude through
the top of the nut. At that time, the maximum torque required
to advance the nut through the next 360° of rotation shall not
exceed the “first installation” torque specified.
The nut is advanced on the bolt until the clamp load specified is
achieved in the bolt. At this time, six to nine thread pitches must
protrude through the nut. The torque required to reach the clamp
load must fall within the specified “locknut tightening torque” to
comply with the torque tension requirements for cadmium plated
nuts.* The nut is then reversed off the bolt until the tensile load on
the bolt declines to zero.
As the nut is reversed another 360°, the torque values will
fluctuate between a highest and lowest reading on the wrench
scale. The highest value must meet or exceed 40% of the first
installation torque and must meet or exceed the first removal
“highest reading minimum.” The lowest value must meet or
exceed the first removal “lowest reading minimum.” The nut is
then backed off until the prevailing torque element disengages
the bolt. The nut is reassembled and removed four more times.
On each reassembly, the nut is assembled to the initial first
off position. This portion of the test need not be conducted
in the load cell, as no clamp load is to be induced in the bolt.
Installation and removal speeds may not exceed 30 rpm, and
sufficient time between torquing cycles is allowed to prevent
overheating of the assembly.
12
LOCKNUT SIZE
(BOLD DIA.) IN.
PROOF LOAD
STRESS PSI
ROCKWELL
HARDNESS
A
No. 4 thru 1 1/2
90,000
C28 max
B,F
No. 4 thru 1
120,000
C28 max
Over 1 thru 1 1/2
105,000
C28 max
C,G
No. 4 thru 5/8
150,000
C24/32
Over 5/8 thru 1
C26/34
Over 1 thru 1 1/2
C26/36
Grade Marking and Aztech Identification – Grade A nuts
need not be marked. Grades B, C, F and G nuts are marked to
identify manufacturer and grade. Markings are in the form of three
(for grades B and F) or six (for grades C and G) grade marking
symbols. The Aztech identification shown below is used as a
substitute for one of the grade marking symbols.
AZTECH MANUFACTURER’S
IDENTIFICATION SYMB0L
Wax, Plating and Prevailing Torque - Wax is clean and dry to
the touch and is recommended as a supplementary lubricant
on all locknuts. Wax does not deteriorate and helps reduce
installation torque and galling. Various platings when applied
to locknuts and mating parts can create significant changes in
the prevailing torque and torque tension relationships.
Aztech Locknut Company can help to evaluate the effect of
these variables.
Locknut Specifications
Proof Loads, Clamp Loads, and Prevailing-Torques for Coarse Thread Series
Grades A, B, and C Hex Nuts and Grades F and G Hex Flange Nuts
NUT
GRADE A NUTS
SIZE
AND
THREADS PROOF CLAMP
PER INCH LOAD lb LOAD lb
4 – 40
6 – 32
8 – 32
10 – 24
12 – 24
1/4 – 20
5/16 – 18
3/8 – 16
7/16 – 14
1/2 – 13
9/16 – 12
5/8 – 11
3/4 – 10
7/8 – 9
1 – 8
1-1/8 – 7
1-1/4 – 7
1-3/8 – 6
1-1/2 – 6
540
820
1,250
1,550
2,200
2,900
4,700
7,000
9,550
12,800
16,400
20,300
30,000
41,600
54,500
68,700
87,200
104,000
126,000
250
370
580
720
1,000
1,300
2,150
3,200
4,400
5,850
7,550
9,300
13,800
12,400
15,000
18,900
24,000
28,700
34,800
GRADE B NUTS
PROOF
LOAD lb
720
1,100
1,700
2,100
2,900
3,800
6,300
9,300
12,800
17,000
21,800
27,200
40,100
55,400
72,700
80,100
101,700
121,300
147,500
CLAMP
LOAD lb
380
580
900
1,100
1,550
2,000
3,350
4,950
6,800
9,050
11,600
14,500
21,300
29,500
38,700
42,100
53,500
63,800
77,600
GRADE C NUTS
PROOF
LOAD lb
910
1,350
2,100
2,600
3,650
4,750
7,850
11,600
15,900
21,300
27,300
33,900
50,100
69,300
90,900
115,000
145,000
173,000
211,000
CLAMP
LOAD lb
550
810
1,250
1,550
2,200
2,850
4,700
6,950
9,600
12,800
16,400
20,300
30,100
41,600
54,600
69,000
87,000
104,000
127,000
PREVAILING-TORQUE
FIRST
INSTALL
MAX lb in
FIRST
REMOVAL
MIN lb in
THIRD
REMOVAL
MIN lb in
4.0
8.0
12.0
17
27
40
80
110
135
204
300
420
540
840
1080
1200
1320
1620
1800
1.0
1.5
2.0
2.5
3.5
5.0
8.0
12.0
17
22
30
39
58
88
120
150
188
220
260
0.2
0.5
0.5
1.0
1.0
1.5
2.5
4.0
5.0
7.5
10.0
12.5
20
30
40
50
60
70
90
GRADE F NUTS
PROOF
LOAD lb
CLAMP
LOAD lb
3,800
6,300
9,300
12,800
17,000
21,800
27,200
40,100
2,000
3,350
4,950
6,800
9,050
11,600
14,500
21,300
GRADE G NUTS
PROOF
LOAD lb
4,750
7,850
11,600
15,900
21,300
27,300
33,900
50,100
CLAMP
LOAD lb
2,850
4,700
6,950
9,600
12,800
16,400
20,300
30,100
Proof Loads, Clamp Loads, and Prevailing-Torques for Fine Thread Series
Grades A, B, and C Hex Nuts and Grades F and G Hex Flange Nuts
NUT
GRADE A NUTS
SIZE
AND
THREADS PROOF CLAMP
PER INCH LOAD lb LOAD lb
4 – 48
600
6 – 40
900
8 – 36
1,350
10 – 32
1,800
12 – 28
2,300
1/4 – 28
3,300
5/16 – 24 5,200
3/8 – 24
7,900
7/16 – 20 10,700
1/2 – 20 14,400
9/16 – 18 18,300
5/8 – 18 22,900
3/4 – 16 33,600
7/8 – 14 45,800
1 – 14 61,100
1 – 12 59,700
1-1/8 – 12 76,900
1-1/4 – 12 96,600
1-3/8 – 12 118,000
1-1/2 – 12 142,000
270
420
610
840
1,050
1,500
2,400
3,600
4,900
6,550
8,350
10,500
15,400
12,600
16,800
16,400
21,200
26,600
32,500
39,100
GRADE B NUTS
PROOF
LOAD lb
790
1,200
1,750
2,400
3,100
4,350
6,950
10,500
14,200
19,200
24,400
30,700
44,800
61,100
81,500
79,600
89,900
113,000
138,000
166,000
CLAMP
LOAD lb
420
640
930
1,300
1,650
2,300
3,700
5,600
7,550
10,200
13,000
16,300
23,800
32,400
43,300
42,300
47,500
59,700
72,900
87,700
GRADE C NUTS
PROOF
LOAD lb
990
1,500
2,200
3,000
3,900
5,450
8,700
13,200
17,800
24,000
30,400
38,400
56,000
76,400
101,900
99,500
128,000
161,000
197,000
237,000
CLAMP
LOAD lb
600
900
1,300
1,800
2,350
3,250
5,200
7,900
10,700
14,400
18,300
23,000
33,600
45,800
61,100
59,700
76,800
96,600
118,000
142,000
PREVAILING-TORQUE
FIRST
INSTALL
MAX lb in
FIRST
REMOVAL
MIN lb in
THIRD
REMOVAL
MIN lb in
4.0
8.0
12.0
17
27
40
80
110
135
204
300
420
540
840
1080
1080
1200
1320
1620
1800
1.0
1.5
2.0
2.5
3.5
5.0
8.0
12.0
17
22
30
39
58
88
120
120
150
188
220
260
0.2
0.5
0.5
1.0
1.0
1.5
2.5
4.0
5.0
7.5
10.0
12.5
20
30
40
40
50
60
70
90
GRADE F NUTS
PROOF
LOAD lb
4,350
6,950
10,500
14,200
19,200
24,400
30,700
44,800
CLAMP
LOAD lb
2,300
3,700
5,600
7,550
10,200
13,000
16,300
23,800
GRADE G NUTS
PROOF
LOAD lb
5,450
8,700
13,200
17,800
24,000
30,400
38,400
56,000
CLAMP
LOAD lb
3,250
5,200
7,900
10,700
14,400
18,300
23,000
33,600
SPECIFICATIONS FROM IFI 100/107 2002 REVISION • HEX NUT AND JAM NUT PERFORMANCE PER SAE J995
13
Locknut Applications
TUBING
CONNECTION
Aztech prevailing torque locknuts resist rotation due to
a self contained locking feature. As all-metal locknuts,
they have few environmental limitations. Removal torque
values tend to decline with each installation. The rate
of decline varies with our different locknut products.
To function properly, the locking feature must engage
fully formed threads. A new design must allow for bolt
threads of sufficient length so that starting threads
remain beyond the nut’s locking element.
CASTER
SLIDE BRACKET
AXLE CLAMP
PIVOT ARM
VALVE HANDLE
SPRING LOADED
ASSEMBLY
Grade
Specified Minimum Tensile of Bolt
A
Not greater than 90,000 psi
B&F
Not greater than 120,000 psi
C
More than 105,000 less than 150,000
G
More than 120,000, less than 150,000
As the locknut’s deformed threads are assembled with
standard form threads, it is possible that one or both may
be damaged. Damage can be minimized by selecting
fasteners of compatible or similar strength grades.
The Sales Department at Aztech Locknut Company
fully understands application parameters and can be
extremely helpful in locknut product selection.
Many of these locknuts, long thought to be proprietary
items, are now available from stock eliminating the need
for large manufacturing minimums and long lead times.
We are able to cross reference other manufacturers part
numbers and quote on a locknut that is comparable
in performance.
Samples are available for engineering approval
as necessary.
2675 White Oak Circle
Aurora, IL 60504
Toll Free 800.321.LOCK (5625)
Local 630.236.3200
Fax 630.236.3210
14
sales@aztechlocknut.com
www.aztechlocknut.com