Lock nuts
Lock nuts are threaded onto the threaded portion of shafts, adapter sleeves, or withdrawal sleeves to axially secure and position components such as rolling bearings and gears. They are tightened using a hook spanner engaged in the notches on the outer periphery, and secured against rotation with lock washers, fixing clips, or locking plates in standard types (KM, HM, N, AN series, etc.), or with set screws or locking pins in integrated locking-device and precision lock nut types. Threads are available in metric coarse and fine pitch, as well as trapezoidal threads for large bearings and inch series. They are also used to press bearings onto tapered shafts and to remove bearings using sleeves.
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Lock nuts
KMTA Precision Lock Nut with Locking Pin
Metric precision lock nut with locking pin. Supports M25 to M200 and uses matching B Series spanner.
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Lock nuts
KMD Precision Lock Nut with Axial Locking Screw
A precision lock nut equipped with an axial locking screw. Compatible with M20 to M105.
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Lock nuts
N・AN Inch-Series Lock Nut
Lock nut for securing inch-series bearings. Used in combination with a matching fixing plate and spanner.
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Lock nuts
PL Fixing Plate
A fixing plate that secures inch-series lock nuts. Includes two hex bolts and one wire.
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Lock nuts
KMK Integrated Fixture Lock Nut
Metric lock nut with integrated fixture. Supports M10 to M100, combining a matching spanner and set screw.
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Lock nuts
KMFE Lock Nut with Set Screw
Metric lock nut with set screw. Supports M20 to M200, with many part numbers.
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Lock nuts
KMT Precision Lock Nut with Fixing Pin
Metric precision lock nut with fixing pin. Supports M10 to M200.
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Lock nuts
KM(L) / HM ..T Lock Nut
Lock nut for fixing bearings to a shaft. Available in M10x0.75 to M200x3 and Tr210x4 to Tr280x4.
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Lock nuts
HM(E) Lock Nut
Large lock nut with trapezoidal thread for large bearings. Used in combination with a fixing clip. Available in Tr220x4 to Tr1120x8.
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Lock nuts
N and AN Inch-Series Lock Nuts
Lock nuts with inch-series threads. Supports thread sizes from 0.391 to 10.192 in.
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Lock nuts
Lock Nuts (KM, HM, N, AN Series, etc.)
Lock nuts for securing bearings and components on shafts or adapter sleeves. Multiple series with different fixing methods are available, so select according to application.
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Lock nuts
Precision Lock Nut (KMK Series, KMFE Series, KMT(A) Series, KMD Series)
Precision lock nut for securing bearings to a shaft. Available in four types: integrated fixing type, set screw type, locking pin type, and axial set screw type, each providing fixing force suited to the application.
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Lock nuts
Lock Nut (HM(E)・N・KM(L)・AN Series)
Standard metric and inch lock nuts. Used in combination with lock washers, retaining clips, and retaining plates.
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How to choose Lock nuts
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1. Select the size and standard to match the shaft thread
The nut must fully match the thread of the shaft or sleeve. Metric fine pitch such as M10×0.75, trapezoidal threads such as Tr220×4, and inch series (ANSI/ABMA) are all listed, so verify the nominal diameter, pitch, and thread standard against the drawing.
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2. Do not confuse thread standard series
Metric KM and HM series and inch N and AN series may look similar but are not interchangeable. Some larger sizes in certain series use trapezoidal threads, so confirm the original standard when repairing existing equipment.
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3. Decide the anti-rotation method
Methods using lock washers, fixing clips, or locking plates require a keyway on the shaft. Integrated types that rotate-lock with set screws or locking pins do not require a keyway and allow quick installation. Also confirm whether accessories are required.
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4. Verify axial load capacity
Nuts receive thrust loads and pressing force during tightening. Listed axial load capacities range widely from 20 to 1340 kN, so confirm sufficient margin against the axial load on the bearing and the force required to press onto a tapered shaft.
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5. Check side face runout for precision applications
In applications such as main spindles with high rotational speed and accuracy, if the nut side face runs out relative to the thread, the bearing tilts and rotational accuracy decreases. Select a precision lock nut and check the axial runout value of the reference side face.
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6. Check outer diameter and width for clearance
Confirm that the nut outer diameter does not interfere with housings or seals, and that the width fits within the thread length of the shaft. Also confirm the applicable spanner number used for tightening and the recommended tightening torque.
This guide was written by AI based on the listed products' documents and specification items. Check each manufacturer's documents before adopting.