Engineering Design SKF Bearing Puller

Title: SKF Mechanical Bearing Easy Puller

Picture 1: SKF Bearing Puller

1.0 Product Specifications

It is equipped with spring-operated arms and a solid design; SKF's patented Easy Pull is

one of the most user-friendly and safe tools on the market. The spring-operated arms

enable the user to position the puller behind the component with just one movement. The

mechanical TMMA series consists of 3 (TMMA 60, TMMA 80 and TMMA 120) pullers

differing in size and withdrawal force.

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Engineering Design SKF Bearing Puller

2.0 Literature Review

It is designed as a tool to make the removal and installation of bearings simple and

efficient, bearing pullers. In some cases, the configuration of the puller will allow the

extraction of both gears and bearings, including those that are connected with a series of

shafts within the mechanism. Different sizes of bearing pullers make it possible to use the

device on everything from a pair of skates to complicated industrial machinery.

Handheld models of bearing pullers are usually constructed along lines that are similar to

a pair of scissors. The main section of tongs are controlled by simple inserts that allow

for the hand to easily open and close the mechanism. Small flat points at the end of the

tongs make it possible to easily insert the device into a gear box or other gear section

containing the individual bearings and easily remove one or more of the small

components. At the same time, the pullers can also be used to place fresh bearings back

into the mechanism, without the need to completely disassemble the entire apparatus.

Larger versions of bearing pullers are made to use in many factories. Since

manufacturing plants use equipment that runs with the use of gears, the ability to replace

worn bearings quickly and efficiently is important to maintaining production quotas.

Industrial sized bearing pullers make this possible with little or not downtime for the

production process.

Along with working for removing and installing bearings, some newer versions of the

bearing puller include a small extraction tool that helps to serve as a guide for the tongs.

This addition has made it possible to work with the bearings in significantly less time

than required with earlier models.

Handheld bearing pullers can be purchased at any hardware store. The sizes range from

simple models that work well with small toys and appliances to larger versions that are

ideal for work on bicycles and smaller motorized vehicles and household tools. More

sophisticated models are available from companies that supply bearings for various types

of machinery.

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Engineering Design SKF Bearing Puller

3.0 Designer Background

Developer and Manufacturer: SKF

With more than 30 years of experience in developing, manufacturing and global

distribution of pullers for bearing applications, SKF Maintenance Products offers a wide

range of bearing pullers each specially designed for specific applications. It specifically

designed for dismounting bearings from housings where the fit is on the outer ring.

The patent pending, SKF designed offer fast and easy bearing dismounting. The

extractors are designed according to bearing bore diameters. After selecting the

appropriate extractor and threading it onto the sliding hammer, the extractor is inserted

through an opening in the inner ring and is fixated with a secure grip, behind the inner

ring. Sliding the weight of the hammer towards the handle generates high impact puller

force and the bearing is rapidly and safely dismounted.

4.0 Advantages and Disadvantages

4.1 Advantage

1- Can result in compromising the machine's efficiency and lifetime during

dismounting bearings such as the shaft or housing, as damage.

2- Bearings are sometimes dismounted to maintain or replace other components of the

machine. These bearings are often re-used.

3- Selecting the correct dismounting methods and tools is then essential in reducing the

risk of damaging the bearing, allowing it to be used again.

4- Study design allows dismounting of components even in the tightest application in a

safe manner.

5- The unique red rings spring-operated opening mechanism allows the Easy Pull to be

placed behind the component with one movement of the hands.

6- Self-locking arms help prevent the risk of puller slipping under load

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Engineering Design SKF Bearing Puller

7- Double hexagonal heads allow easier application of withdrawal force

8- Self-centering capability and nosepiece help to avoid damage to shaft

9- Efficient use of time due to quick dismounting

10- Available in three sizes with a withdrawal force of 60, 80 or 120 kN (6.7, 9.0 or 13.5

ton US), enabling easy selection.

11- The tool set is packed in an easy to select and practical special box of steel.

4.2 Disadvantages

1- The inner rings of cylindrical roller bearings generally have a tight interference fit,

which requires high forces to dismount. In such cases, using a puller can cause damage to

the shaft and ring, and can be hazardous to the operator.

2- Choosing the right puller for the job is critical. Not only the puller type, but also its

maximum withdrawal capacity is crucial for completing any dismounting job safely and

easily.

3- Puller overload can result in breakage of the puller's arms and/or beam and therefore

should be avoided. This breakage can damage the bearing or shaft and can cause personal

injury

4- Bearing puller with was not an ergonomic sliding hammer and a selection of spring-

operated extractors. It was be not an ergonomic job to user.

5- Overloading a puller can result in puller arm or spindle breakage, causing injury to the

operator

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Engineering Design SKF Bearing Puller

4.3 Recommendation

1- Hydraulic techniques are often the preferred method for dismounting larger bearings as

well as other components compared to bearing puller. These techniques, which employ

hydraulic pumps, nuts and oil injectors, allow the application of substantial forces to

dismount bearings or other components. It can make the user with an ergonomic job to be

done.

2- In general, it is recommended to use a three-arm puller rather than a two-arm one, as

the three-arm puller is more stable.

3- Selecting the correct dismounting methods and tools is therefore of utmost importance

for reducing the risk of personal injuries.

4- Using heating equipment facilitates easy and quick dismounting while reducing the

risk of damage to the ring and shaft

5.0 Operation of Bearing Puller

Depending on bearing size and mounting conditions, the extractor with the suitable

dimensions is selected. The span can be adjusted by shifting the lever system on the

cylinder. During the extraction process the lever system causes self-locking of the arms

and ensures a good grip. Rolling bearing rings that are extracted correctly remain

undamaged.

Complete bearings where the extraction force is transmitted through the a rings where the

extraction force is transmitted through the rolling elements usually become

unserviceable.

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Engineering Design SKF Bearing Puller

6.0 Safety Handling of Easy puller

For optimum safety when dismounting bearings:

Always wear protective clothing and goggles when dismounting bearings

When dismounting bearings using pullers, make sure to select a suitable puller for

the application with sufficient pulling force in order to reduce the risk of puller

overload. A safety blanket fitted around the puller and bearing helps reduce the

risk of injury in case the bearing, puller's arm or spindle break

For your own safety, do not strike the bearing directly with any hard object such

as a hammer or chisel

Apply dismounting force to part of bearing that has highest fit

7.0 Material Specifications

Material: Alloy Steel

Process: Heat Treatment

Finish: Dull Chrome finish

Alloy steel is steel alloyed with a variety of elements in total amounts of between 1.0%

and 50% by weight to improve its mechanical properties. Alloy steels are broken down

into two groups: low alloy steels and high alloy steels.

The following are a range of improved properties in alloy steels (as compared to carbon

steels): strength, hardness, toughness, wear resistance, hardenability, and hot hardness. In

order to achieve some of these improved properties the metal may require heat treating.

Alloy steel is often subdivided into two groups: high alloy steels and low alloy steels. The

difference between the two is defined somewhat arbitrarily. However, most agree that

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Engineering Design SKF Bearing Puller

any steel that is alloyed with more than eight percent of its weight being other elements

beside iron and carbon, is high alloy steel. Low alloy steels are slightly more common.

The physical properties of these steels are modified by the other elements, to give them

greater hardness, durability, corrosion resistance, or toughness as compared to carbon

steel. To achieve such properties, these alloys often require heat treatment. Perhaps the

most well-known alloy steel is stainless steel. This is a steel alloy with a minimum of

10% chromium content.

If the carbon level in a low alloy steel is in the medium to high range, it can be difficult to

weld. If the carbon content is lowered to a range of 0.1% to 0.3%, and some of the

alloying elements are reduced, the steel can achieve a greater weld ability and formability

while maintaining the strength that steel is known for. Such metals are classified as high

strength, low alloy steels.

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Engineering Design SKF Bearing Puller

How to purchase a Bearing Puller Using Datasheet

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Engineering Design SKF Bearing Puller

Picture 2: 3-D View of Bearing Puller

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Engineering Design SKF Bearing Puller

Picture 3: Model of Bearing Puller Using Solid Works

Picture 4: Dimension of Simple Bearing puller

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Engineering Design SKF Bearing Puller

Picture 5: Three arm pull for external pull

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Engineering Design SKF Bearing Puller

Technical Data Sheet of Mechanical Easy Puller

 Technical data TMMA 60

 General Width of grip external, minimum 36 mm (1.4 in)  Width of grip external, maximum 150 mm (5.9 in) Effective arm length 150 mm (5.9 in) Maximum withdrawal force 60 kN (6.7 ton US) Total weight 4,0 kg (8.8 lb) Claw dimensions Claw height 7,5 mm (0.30 in) Claw length 15 mm (0.6 in) Claw width 20 mm (0.8 in) Force generators Hexagon on puller or adapter 27 mm Hexagon on mechanical spindle 17 mm Max torque 105 Nm (75 lbf ft) Diameter nose piece 24 mm (0.9 in) Adapter: possible to upgrade  to hydraulic version

 no

 Spare parts Arm TMMA 60-1 Spindle with nose piece (and adapter) TMMA 60-2 Opening mechanism TMMA 60-3 Accessories Puller protection blanket TMMX 210 Gloves TMBA G11W Hydraulic spindle - Spindle grease LGEV 2/0.035 Tri- section pulling plates TMMS 50

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