M/s SHARAD ENGINEERING SOLUTIONS

Corporate

Poor lubrication accounts for over 36% of premature bearing failures SKF lubricants offer major advantages: Designed and tested to perform under real conditions Product data include specific test results enabling a better selection Strict quality control of every production batch helps ensure consistent performance SKF Lubricant Selection - The basic bearing grease selection chart provides you with quick suggestions on the most commonly used greases in typical applications. Greases for a wide range of applications • LGMT 2 • LGMT 3 • LGEP 2 • LGWA 2 • LNEP 2 - High load extream pressure grease Greases for high load applications • LGHB 2 • LGEV 2 • LGEP 2 Greases for high temperature applications • LGHP 2 • LGHB 2 Food grade lubricants • LGFP 2 • LFFG

Deep groove ball bearings are particularly versatile. They are suitable for high and very high speeds, accommodate radial and axial loads in both directions and require little maintenance. Because deep groove ball bearings are the most widely used bearing type, they are available from SKF in many designs, variants and sizes. In addition to the bearings presented in this section, deep groove ball bearings for special applications are shown under Engineered products. These bearings include: Sensor bearing units High temperature bearings and bearing units Bearings with Solid Oil INSOCOAT bearings Hybrid bearings No Wear coated bearings

Sealing solutions customized for your system performance Seals have a crucial impact on system performance. Life and reliability of what is often considered a simple component can make all the difference to your products and operations. SKF has more than 100 years of experience in various industries and applications, and is the only company that can support key aspects of the sealing system through its knowledge of bearings, seals, lubrication and associated science and technology. SKF offers expert advice and provides support throughout the life cycle of your sealing system.

Deep groove ball bearings are particularly versatile. They are suitable for high and very high speeds, accommodate radial and axial loads in both directions and require little maintenance. Because deep groove ball bearings are the most widely used bearing type, they are available from SKF in many designs, variants and sizes.

In addition to the bearings presented in this section, deep groove ball bearings for special applications are shown under Engineered products. These bearings include:

• Sensor bearing units
• High temperature bearings and bearing units
• Bearings with Solid Oil
• INSOCOAT bearings
• Hybrid bearings
• No Wear coated bearings

Insert bearings (SKF Y-bearings) are based on sealed deep groove ball bearings in the 62 and 63 series, but have a convex outer ring and in most cases an extended inner ring with a specific locking device, enabling quick and easy mounting onto the shaft.

Angular contact ball bearings have inner and outer ring raceways that are displaced relative to each other in the direction of the bearing axis. This means that these bearings are designed to accommodate combined loads, i.e. simultaneously acting radial and axial loads.

The axial load carrying capacity of angular contact ball bearings increases as the contact angle increases. The contact angle is defined as the angle between the line joining the points of contact of the ball and the raceways in the radial plane, along which the combined load is transmitted from one raceway to another, and a line perpendicular to the bearing axis.

The most commonly used designs are:

• Single row angular contact ball bearings
• Double row angular contact ball bearings
• Four-point contact ball bearings

Self-aligning ball bearings have two rows of balls, a common sphered raceway in the outer ring and two deep uninterrupted raceway grooves in the inner ring. They are available open or sealed. The bearings are insensitive to angular misalignment of the shaft relative to the housing, which can be caused, for example, by shaft deflection.

Features:

• Accommodate static and dynamic misalignment: The bearings are self-aligning like spherical roller bearings or CARB bearings.
• Excellent high-speed performance: Self-aligning ball bearings generate less friction than any other type of rolling bearing, which enables them to run cooler even at high speeds.
• Minimum maintenance: Because of low heat generation, the bearing temperature is lower, leading to extended bearing life and maintenance intervals.
• Low friction: Very loose conformity between balls and outer ring keeps friction and frictional heat at low levels.
• Excellent light load performance: Self-aligning ball bearings have low minimum load requirements.
• Low noise: Self-aligning ball bearings can reduce noise and vibration levels, for example, in fans.

SKF thrust ball bearings are manufactured as single direction or double direction thrust ball bearings. They are designed to accommodate axial loads only and must not be subjected to any radial load.

Features:

• Separable and interchangeable: The separable components of SKF thrust ball bearings are interchangeable. This facilitates mounting and dismounting, and maintenance inspections.
• Initial misalignment: Bearings with sphered housing washer(s) can accommodate initial misalignment.
• Interference fit: Shaft washers have a ground bore to enable an interference fit. The bore of the housing washer is turned and always larger than the shaft washer bore.

SKF cylindrical roller bearings are available in many designs, series and sizes. The major design differences between the bearings presented in this section are in:

• the number of roller rows (one, two or four)
• the type of cage (with, without or special designs)
  • Bearings with a cage can accommodate heavy radial loads, rapid accelerations and high speeds.
  • Full complement bearings (without a cage) incorporate a maximum number of rollers and are therefore suitable for very heavy radial loads at moderate speeds.
  • SKF high-capacity cylindrical roller bearings combine the high load carrying capacity of a full complement bearing with the high speed capability of a bearing with cage.
• the configuration of the inner and outer ring flanges (position and number of guide flanges)

Features:

• High load carrying capacity
• High stiffness
• Accommodate axial displacement: Except for bearings with flanges on both the inner and outer rings.
• Low friction: The open flange design, together with the roller end design and surface finish, promote lubricant film formation resulting in lower friction and higher axial load carrying capacity.
• Long service life: The logarithmic roller profile reduces edge stresses at the roller/raceway contact and sensitivity to misalignment and shaft deflection.
• Enhanced operational reliability: The surface finish on the contact surfaces of the rollers and raceways supports the formation of a hydrodynamic lubricant film.

SKF Needle Roller Bearings are bearings with cylindrical rollers that are small in diameter relative to their length. The modified roller/raceway profile prevents stress peaks to extend bearing service life.

SKF supplies Needle Roller Bearings in many different designs, series and in a wide range of sizes, which make them appropriate for a wide variety of operating conditions and applications.

SKF Explorer Tapered Roller Bearings for your toughest challenges.

In today’s industrial world, you need solutions that are able to handle the toughest challenges and ready to meet even greater demands. Solutions that work harder, work longer and work safer. Solutions robust enough to cope with challenging conditions and testing environments. Solutions that deliver longer and more consistent periods of uptime to ensure greater productivity and efficiency.

We understand what markets demand and the size of the challenges you face. Only through understanding these challenges can we come up with better, more effective solutions.

• You need a tapered roller bearing that can handle high loads
• A tapered roller bearing that is both durable and reliable
• A tapered roller bearing that is not going to compromise your productivity and safety
• A tapered roller bearing that can withstand challenging and extreme conditions

Tapered Roller Bearings have tapered inner and outer ring raceways as well as tapered rollers. They are designed to accommodate combined loads, i.e. simultaneously acting radial and axial loads. The projection lines of the raceways meet at a common point on the bearing axis to provide a true rolling action and therefore low frictional moments during operation. The axial load carrying capacity of tapered roller bearings increases with increasing contact angle α.

Spherical Roller Bearings have two rows of symmetrical rollers, a common sphered outer ring raceway and two inner ring raceways inclined at an angle to the bearing axis. The centre point of the sphere in the outer ring raceway is at the bearing axis.

Features:

• Accommodate misalignment: Spherical roller bearings are self-aligning like self-aligning ball bearings or CARB bearings.
• High load carrying capacity: Spherical roller bearings are designed to accommodate both heavy radial loads and axial loads in both directions.
• Long service life: The rollers are manufactured to such tight dimensional and geometrical tolerances that they are practically identical in a roller set. The symmetrical rollers self-adjust, providing optimal load distribution along the roller length and together with the special profile prevent stress peaks at the roller ends.
• Low friction: Self-guiding rollers keep friction and frictional heat at low levels. A floating guide ring guides unloaded rollers so that they enter the load zone in the optimal position.
• Robust: All SKF spherical roller bearings contain strong window- or prong-type cages.

CARB toroidal roller bearings have one row of long, slightly barrel-shaped symmetrical rollers and torus-shaped raceway profiles. They are non-locating bearings and accommodate exclusively radial loads. CARB bearings are often used to replace the non-locating spherical roller bearing in a locating/non-locating bearing arrangement.

Features:

• Accommodate misalignment: CARB bearings are self-aligning like spherical roller bearings or self-aligning ball bearings.
• Accommodate axial displacement: CARB bearings compensate for thermal expansion of the shaft like cylindrical or needle roller bearings.
• Wide assortment of dimension series: CARB bearings are available with the same boundary dimensions as corresponding spherical roller bearings, self-aligning ball bearings, cylindrical roller bearings and needle roller bearings.
• Long service life: The special roller profile prevents stress peaks at the roller ends.
• Low friction: Self-guiding rollers keep friction and frictional heat at low levels.
• Improved wear resistance: All CARB bearings are upgraded SKF Explorer bearings.
• Low noise: CARB bearings can reduce noise and vibration levels, for example, in paper machines and fans.

Long bearing system life: 

CARB bearings provide benefits in self-aligning bearing arrangements. With a CARB bearing in the non-locating position, there are no internally induced axial forces, which results in multiple benefits.

Conventional SKF ball bearing units consist of:

• An insert bearing (Y-bearing) which is based on a single row deep groove ball bearing with a sphered (convex) outside surface and an extended inner ring
• Ahousing, which has a correspondingly sphered but concave bore

Ball bearing units can accommodate moderate initial misalignment, but normally do not permit axial displacement. The SKF assortment includes units to ISO standards, North American standards, and Japanese Industrial Standards.

New SKF UC range, designed for JIS* equipment

You need a robust and reliable ball bearing unit solution, one that’s easy to install, simple to order and improves productivity. SKF now offers a product that matches your operational and application requirements.

At SKF, we have developed a range of ball bearing units, called “UC range”, designed to be interchangeable with JIS* equipment. These SKF UC bearing units are designed with a set screw locking feature, to operate in environments where systemic vibrations are characteristic application conditions.

Features:

• Enhanced set screw for increased reliability
• A solid base and solid feet for increased cleanliness and better bearing unit support.
• Supplied with rugged integral seal protected with an additional flinger to help exclude contaminants
• Optional end cover for safety

Benefits:

• Comply with JIS (Japanese Industrial Standard)
• Full Range assortment
• Higher Reliability
• Better availability

World-class quality housings for demanding applications

SKF offers a range of small to large size split plummer block housings primarily designed for self-aligning ball bearings and spherical roller bearings mounted directly on cylindrical shafts or on adapter sleeves. The design of the housings provides different options for the selection of bearings and methods of mounting.

Features:

• Grease level marking
• Better heat dissipation
• Dimples to locate accessories and improved lubrication facilities
• Improved markings on the housings
• Easy & Reliable mounting

Benefits:

• Reduced unplanned downtime
• Reduced maintenance
• Easy serviceability
• Improved overall performance
• Enhanced bearing performance
• Ease of ordering – housing & seal as one part number

SNL and SE plummer block housings are the most popular SKF bearing housings on the market, developed to be the first choice for design, quality and economy.

SE plummer block housings are a new generation with a number of new features and a stronger material grade. They are available from size 507 up to and including 511-609.

SNL and SE plummer block housings enable the incorporated bearings to achieve maximum service life with less need for maintenance. Different housing variants and seal designs are available, making the use of tailored housings virtually unnecessary and enabling costeffective bearing arrangements to be made.

Types:

• Self-aligning ball bearings
• Spherical roller bearings
• CARB toroidal roller bearings

Dimension Series:

• 02, 03, 22, 23, 32

Diameter Range:

• 20 to 160 mm
• 3/4 to 5 1/2 in.

Typical shaft-bearing combination:

• Plain shaft with bearing on an adapter sleeve
• Stepped shaft with bearing on a cylindrical seat

Seals:

• Four-lip
• V-ring
• Labyrinth
• Heavy-duty
• Felt

Kybrication:

• Grease
• Oil

Materials:

• Grey cast iron
• Spheroidal graphite cast iron

Mounting:

• Two-bolt mounting
• Four-bolt mounting

Compliance to standard:

• ISO 113:2010 (two-bolt plummer block housings)

Supersedes

• SN, SNA, SNH series

SONL plummer (pillow) block housings are specially designed for oil lubrication. They can accommodate high temperatures and bearings operating at high speeds. They have a strong, stiff design and are characterized by a number of built-in features that maximize the effects of the lubricant and extend bearing service life.

SONL housings can be found in applications ranging from fans and flywheels to paper machines and emergency power generators.

Bearing types

• Self-aligning ball bearings
• Spherical roller bearings
• CARB toroidal roller bearings

Bearing dimension series

• 22

Shaft diameter range

• 75 to 240 mm
• 2 15/16 to 8 15/16 in.

Typical shaft-bearing combinations

• Plain shaft with bearing on an adapter sleeve
• Stepped shaft with bearing on a cylindrical seat

Seals

• Labyrinth

Lubrication

• Oil bath lubrication with a pick-up ring
• Circulating oil lubrication systems

Materials

• Grey cast iron
• Spheroidal graphite cast iron

Mounting

• Four-bolt mounting

Compliance to standards

• Not standardized

Supersedes

• SOFN in the 2(00) and 5(00) series

SAF and SAW split pillow (plummer) block housings are popular SKF bearing housings with inch dimensions, developed to be the first choice for design, quality and economy.

SAF and SAW housings enable the incorporated bearings to achieve maximum service life with less need for maintenance. Different housing variants and seal designs are available, making the use of tailored housings virtually unnecessary and enabling cost-effective bearing arrangements.

Bearing types

• Spherical roller bearings (SAF and SAW)
• Self-aligning ball bearings (SAF)
• CARB toroidal roller bearings (SAF)

Bearing dimension series

• 12, 13, 22, 23, 30 (SAF)
• 22, 32 (SAW)

Shaft diameter range

• 1 3/16 to 10 1/2 in. (SAF)
• 3 3/16 to 7 15/16 in. (SAW)

Typical shaft-bearing combinations

• Plain shaft with bearing on an adapter sleeve
• Stepped shaft with bearing on a cylindrical seat

Seals

• Labyrinth
• Contact
• Heavy-duty

Lubrication

• Grease
• Oil

Materials

• Grey cast iron
• Cast steel
• Spheroidal graphite cast iron

Mounting

• Two-bolt mounting
• Four-bolt mounting

FNL flanged housings are well-proven machine parts that provide simple, reliable housing in applications without horizontal frames. They enable the full service life potential of the incorporated bearings to be exploited with less need for maintenance.

Features and benefits:

• Simple mounting
  - Lines cast into the housing flange indicate the centre of the housing bore. Dimples indicate the position for dowel pins.
• Grease guiding system
  - An integrated flange guides grease from the grease fitting into the bearing.
• Low friction seals
  - A low friction, double-lip seal on each side of the housing keeps grease in and contaminants out. These seals allow rotational speeds twice that of traditional felt seals.
• Two predrilled holes for relubrication.
  - The centered hole enables relubrication via a lubrication feature in the bearing. The offset hole enables relubrication from the side.

Adapter sleeves are the most commonly used components for locating bearings with a tapered bore onto a cylindrical seat as they can be used on:

• Plain shafts
• Stepped shafts

They are easy to install and require no additional location on the shaft:

• When used on plain shafts, the bearing can be located at any position on the shaft.
• When used on stepped shafts together with an L-shaped spacer ring, the bearing can be accurately positioned axially, thereby facilitating bearing mounting and dismounting.

Withdrawal sleeves can be used to mount bearings with a tapered bore onto the cylindrical seat of stepped shafts . The sleeve is pressed into the bore of the bearing inner ring, which abuts a shaft shoulder or similar fixed component. The sleeve is located on the shaft by a nut or an end plate. KM or HM lock nuts with appropriate locking devices are suitable. Lock nuts are not supplied with the sleeve and must be ordered separately. End plates are not produced by SKF.

Appropriate nuts that facilitate the mounting and dismounting of bearings on sleeves and those required to remove the withdrawal sleeve:

• are listed in the product table
• must be ordered separately

SKF recommends using a hydraulic nut to press the withdrawal sleeve into the bearing bore, as a considerable amount of force is required to overcome the friction between the bearing, sleeve and shaft.

Lock nuts are used to locate bearings onto a shaft. Additionally, they can be used to mount bearings with a tapered bore onto tapered shaft seats and adapter sleeves, and to dismount bearings from withdrawal sleeves. Lock nuts are also frequently used to secure gears, belt pulleys and other machine components.

Lock nuts have to be secured to prevent unintentional loosening by:

• A locking device that engages a keyway in the shaft or key slot in the adapter sleeve, or
• A locking mechanism integrated in the nut
  When choosing or replacing a lock nut, there are a number of factors that should be taken into consideration. They include, but are not limited to:
  - Space – axial and radial
  - Shaft rotation – one or both directions
  - Axial loads
  - Dynamic behavior of the application
  - Cost and downtime of machining keyways in shafts vs. other locking methods
  - Ease and frequency of assembly and disassembly
  - Precision

Electric motors, generators and associated equipment are at risk when an electric current passes through their bearings. This can damage the contact surfaces of rolling elements and raceways in the bearings (electrical erosion) and rapidly degrade the grease. An additional risk in electric motors and generators comes from high frequency currents caused by the inherent stray capacitance. The risk of damage increases where the application uses a frequency converter.

INSOCOAT bearings:

• Are designed to prevent electric current from passing through the bearing
• Have the external surfaces of either their inner or outer ring coated with an insulating aluminium oxide layer, by applying a sophisticated plasma-spray process for an outstanding quality finish
• Are a very cost-effective solution compared with other insulation methods

Bearing features:

Protection against electrical erosion
- With insulating properties integrated into the bearing, INSOCOAT bearings can improve reliability and increase machine uptime by virtually eliminating the problem of electrical erosion.

High electrical resistance
- The aluminium oxide coating provides a minimum electrical resistance of 200 MΩ and can withstand voltages up to 3000 V DC.

Consistent electrical performance
- Plasma-spray coatings are normally hygroscopic and, therefore, vulnerable to penetration caused by condensation. To protect against this effect, INSOCOAT bearings are treated with a unique sealant.

SKF high temperature bearings and bearing units are designed to deliver increased reliability, reduced complexity and decreased environmental impact in operating temperatures up to 350 °C (660 °F). Because SKF high temperature bearings correspond to the ISO dimensions of grease-lubricated bearings, production efficiencies and cost savings can be realized with a simple change to the SKF bearing solution.

The environmental benefits of SKF high temperature bearings are so significant in many applications that they are included in the "SKF Beyond Zero" product portfolio.

Bearing benefits and features

• Reduced total operating cost
  - The bearings are designed to maintain the radial clearance needed for high temperature operation and so will not seize, even when they cool rapidly, and therefore provide a long service life.
• Virtually maintenance-free operation
  - The bearings are lubricated for life and do not need relubrication. Only variant VA201 without shields requires relubrication.
• Excellent performance under severe conditions:
  - hot conditions
  - dry environments
  - low rotational speeds
• Reduced environmental impact
• Reduced machine design complexity

SKF bearings with Solid Oil are designed for use in applications where high levels of moisture and incidental contact with water and other contaminants are real issues. Bearings with Solid Oil are lubricated for the life of the bearing and cannot be relubricated.
Solid Oil:

• is an oil saturated, polymer material
  - moulded into the bearing, forming very narrow gaps between the rolling elements, raceways and cage(s), enabling the bearing to rotate freely
  - having a porous structure, with millions of micro-pores that retain the lubricating oil by surface tension
• virtually fills all of the free space in the bearing
• releases oil into the narrow gaps, during operation, providing effective minimum quantity lubrication

Bearing features:

• Long service life
  - An increase in operating temperature pushes the oil toward the surface of the polymer material, supporting consistent lubricant supply. During shutdown, any excess oil is re-absorbed back into the polymer material.
• Extended lubricant life
  - With Solid Oil bearings, a large amount of oil is available (two to four times more compared to conventional grease fill).
  - The Solid Oil polymer structure eliminates lubricant churning.
  - Solid Oil is a high-quality synthetic oil that resists oxidation.
• Resists washout
  - Solid Oil cannot be washed out and virtually fills all free space, limiting the amount of wet contamination that can enter the bearing.
  - Water cannot mix with the oil or Solid Oil polymer.

Hybrid bearings have rings made of bearing steel and rolling elements made of bearing grade silicon nitride (Si3N4), which make the bearings electrically insulating.

Bearing features:
Silicon nitride rolling elements can extend bearing service life by offering enhanced bearing performance, even under difficult operating conditions. When compared to same-sized bearings with steel rolling elements, the benefits of hybrid bearings include:

• Protection from electric current damage
  - Hybrid bearings are non-conductive and therefore suitable for applications such as AC and DC motors and generators, where electric currents are present.
• Higher speed capability
  - The density of a silicon nitride rolling element is 60% lower than a same-sized rolling element made of bearing steel. Lower weight and inertia translates into higher speed capability and superior behaviour during rapid starts and stops.
• Long service life
  - The lower frictional heat generated in hybrid bearings, especially at high speeds, contributes to extended bearing service life and extended relubrication intervals.
• High wear-resistance
  - Silicon nitride rolling elements have a higher degree of hardness making hybrid bearings suitable under difficult conditions and contaminated environments.
• High bearing stiffness
  - With a high modulus of elasticity, hybrid bearings offer increased bearing stiffness.