SKF KMF 8 M40x1.5 40x58x11 mm - Bearing Lock Nut

Technical Specifications

The dimensions identify the KMF 8 configuration. The thread diameter is a nominal thread dimension, not the diameter of a smooth cylindrical bore.

What Does KMF 8 SKF Mean?

The designation KMF 8 identifies a specific SKF lock nut configuration.

It must not be confused with SKF KM 8, KMK 8, or KMT 8, even where the nominal thread dimensions are identical.

The series designation is technically important because the locking arrangement, overall dimensions, and installation requirements may differ.

Construction and Operating Principle

SKF KMF 8 is designed to axially locate bearings and other suitable mechanical components on a threaded shaft.

Its construction consists of a threaded nut body and an integrated locking arrangement intended to prevent unintended loosening after installation.

The main functions include:

• Axial positioning of bearings and other shaft-mounted components.

• Applying axial clamping force against an appropriate supporting surface.

• Maintaining the installed position through an integral locking mechanism.

• Allowing installation and removal with suitable mounting tools.

Unlike conventional KM series lock nuts, the KMF design does not require a separate locking washer.

Correct operation depends on thread compatibility, the condition of the mating surfaces, and proper installation of the locking mechanism.

The nut itself does not transmit rolling loads or contain rolling elements.

SKF KMF 8 vs KM 8 and KMT 8

SKF offers different lock nut series for bearing mounting and axial location.

Although some variants share the same thread, their construction and dimensions may differ.

SKF KMF 8 vs KM 8

Both nuts have an M40x1.5 thread and an outside diameter of 58 mm.

However, KMF 8 has a width of 11 mm, while KM 8 has a width of 9 mm.

The locking arrangements are also different. KMF 8 incorporates an integral locking mechanism, whereas KM 8 normally uses a separate locking washer.

KMF 8 and KM 8 are not automatically interchangeable.

SKF KMF 8 vs KMT 8

KMT 8 is a precision lock nut with three locking pins.

It has a larger outside diameter and greater width than KMF 8.

Although both products use an M40x1.5 thread, the differences in construction and installation dimensions must be considered before substitution.

Selection and Interchangeability

Before selecting SKF KMF 8, verify the mechanical requirements of the application.

Important selection criteria include:

• Shaft thread: M40x1.5.

• Nut outside diameter: 58 mm.

• Nut width: 11 mm.

• Available installation space.

• Design of the supporting shoulder or contact surface.

• Required axial location of the bearing.

• Permissible axial loading of the threaded connection.

• Access to the integral locking mechanism.

• Compatibility with the mounting tool.

• Requirements specified by the machine or bearing assembly manufacturer.

A matching thread does not guarantee complete interchangeability.

When considering a lock nut from another SKF series or another manufacturer, dimensional, mechanical, and functional compatibility must be verified.

Applications of SKF KMF 8

SKF KMF 8 is intended for axial location of suitable bearings and mechanical components on shafts with an M40x1.5 thread.

Potential applications include:

• Bearing arrangements requiring axial retention.

• Threaded shaft assemblies.

• Industrial mechanical assemblies using lock nuts with integral locking.

• Bearing mounting arrangements designed for the KMF series.

These are general applications based on the function and construction of the product.

They do not establish confirmed compatibility with a particular machine, gearbox, motor, or OEM assembly.

The suitability of KMF 8 must be verified against the relevant engineering documentation.

Alternative Designations and Reference Formats

Natural reference formats include:

• KMF 8 SKF

• SKF KMF 8

• KMF8 SKF

• SKF KMF 8 Lock Nut

• SKF KMF 8 Bearing Lock Nut

• KMF 8 M40x1.5 Lock Nut

These are alternative descriptive and search formats for the same product, not separate manufacturer part numbers or confirmed interchangeable references.

The official SKF designation remains KMF 8.

Installation and Operating Recommendations

Before installation, inspect the shaft thread, supporting surfaces, and integral locking mechanism.

Ensure that the thread is clean and free from burrs, deformation, or other damage that could prevent correct engagement.

The nut should be tightened using a suitable mounting tool and in accordance with SKF installation instructions and the requirements of the bearing assembly.

Important installation considerations include:

• Confirming thread compatibility before mounting.

• Avoiding cross-threading or damage to the shaft.

• Applying the specified tightening procedure.

• Correctly engaging the integral locking mechanism.

• Checking axial positioning after installation.

• Ensuring that the locking arrangement is functioning correctly.

Do not apply tightening torque values intended for other lock nut series without verifying their suitability.

After installation, confirm that the nut is correctly seated and secured.

Store the product in clean, dry conditions, protecting the thread and locking components against mechanical damage and corrosion.

Frequently Asked Questions - FAQ

What are the dimensions of SKF KMF 8?

SKF KMF 8 has an M40x1.5 thread, an outside diameter of 58 mm, and a width of 11 mm. Its nominal dimensions are 40x58x11 mm.

Is SKF KMF 8 a bearing?

No. KMF 8 is a bearing lock nut used for axial location of bearings and other suitable shaft-mounted components.

What thread does SKF KMF 8 have?

The nut has an M40x1.5 metric thread, with a nominal diameter of 40 mm and a thread pitch of 1.5 mm.

Does SKF KMF 8 require a separate locking washer?

No. KMF 8 incorporates an integral locking mechanism and does not use the separate locking washer arrangement typical of the KM series.

Are SKF KMF 8 and KM 8 interchangeable?

Not automatically. KMF 8 has a width of 11 mm, while KM 8 has a width of 9 mm. Their locking arrangements also differ.

What is the difference between SKF KMF 8 and KMT 8?

KMF 8 is a lock nut with an integral locking mechanism, measuring 58 mm in outside diameter and 11 mm in width. KMT 8 is a precision lock nut with three locking pins, an outside diameter of 65 mm, and a width of 22 mm.

Which mounting tool is suitable for SKF KMF 8?

SKF HN 8-9 is listed as a suitable mounting tool. Compatibility should be checked against the applicable SKF mounting instructions.

Can SKF KMF 8 be reused?

Reuse depends on the condition of the thread, supporting surfaces, and locking mechanism, together with SKF recommendations. A nut with damaged threads or an ineffective locking mechanism should not be reused.

SKF KMF 8 - Key Technical Information

SKF KMF 8 is a bearing lock nut with an integral locking mechanism, designed for axial location of shaft-mounted components. It features an M40x1.5 thread, a 58 mm outside diameter, and an 11 mm width. Its construction differs from SKF KM 8 and KMT 8, so interchangeability requires verification.

SKF Bearing Lock Nuts at simmering.pl

SKF bearing lock nuts, rolling bearings, adapter sleeves, and bearing mounting accessories are available through simmering.pl, a specialist B2B trading platform serving industrial companies, engineers, maintenance departments, and technical purchasing teams.

Our warehouse and order processing facilities are located in Lublin, Poland. We provide worldwide shipping from stock in Poland.

Technical product identification and selection assistance is available based on manufacturer designations, dimensions, and application requirements.