By selecting, maintaining and monitoring critical components and inside rotating plant and machines such as gearboxes, electric motors, pumps and fans, food and beverage processing companies can improve their plant efficiencies, eliminate production downtime and increase the operating life and reliability of plant equipment, says Dr Steve Lacey
In food and beverage processing, production is typically based on highly automated, fast moving processes and systems, where every second of production counts. In these operating environments, the cost of production downtime can equate to hundreds of thousands of pounds per day. Total maintenance costs for a typical food or beverage manufacturer are around 15-20% of total costs.
Although maintenance departments are set up to deal with problems like these, often, because of time and resource constraints, maintenance becomes reactive, with problems around the plant dealt with as they occur rather than in a proactive, planned manner.
Condition monitoring (CM) prevents the unnecessary replacement of components and the subsequent introduction of possible new and unrelated problems. Maintenance teams can benefit from the use of CM technology to predict when failures are likely to occur and plan replacement during production shutdowns. In too many companies, components are replaced on a time basis rather than on a condition basis because this is considered to be the safest option.
However, there are numerous technology safeguards available which, when compared to the cost of lost production, are relatively inexpensive. These safeguards use the latest CM technologies and predictive maintenance systems, including vibration monitoring, wear monitoring and automatic lubrication to protect plant and machines.
Intelligent monitoring
FAG SmartCheck is an extremely compact condition monitoring device from Schaeffler that is ideal for the online monitoring of process-critical plant and machinery, including motors, drives, pumps, HVAC systems and gearboxes.
The device can be used to monitor vibration and temperature, as well as a range of other machine and process-specific parameters. By monitoring these parameters, users are provided with a broad basis of information in real time, which enables the accurate assessment of machine condition.
FAG SmartCheck is easy to operate and requires no special programming skills or knowledge. The scope of delivery includes a number of machine and process-specific parameter templates, which enable the system to be operational within minutes. Visual alarms are indicated via LEDs located on the front of the device housing. Due to its self-learning (Teach-In) mode, the device’s alarm thresholds are adjusted automatically. After set up and commissioning, the unit operates autonomously. The relevant machine parameters are measured and saved continuously in the system, creating a substantial database of historical data over time.
Multi-point lubricators
For food or beverage processing lines where machine uptime is critical, multi-point lubrication systems can be installed, which automatically supply lubricant to rolling bearings without the need for manual intervention.
FAG CONCEPT8, for example, is a cost effective multi-point lubricator from Schaeffler that ensures a constant, optimum supply of grease to rolling bearings. The system is suitable for a wide range of industrial applications, including pumps, fans, compressors, gearboxes and electric motors.
FAG CONCEPT8 provides up to eight separate lubrication points for dispensing precisely metered quantities of lubricant to rolling bearings. The system is fitted with four pairs of lubrication points (eight in total), which are controlled by four individual dispensing pumps.
Unlike other multi-point lubricators, FAG CONCEPT8 enables users to individually control each pump in order to optimise cycle times and volumes of dispensed lubricant. This means the system can be adjusted to meet up to four different bearing sizes, each with varying lubrication requirements. Rather than having to purchase multiple single point lubricators to cope with different bearing lubrication requirements, users can now buy one FAG CONCEPT8.
Bearings for every application
For food, beverage and packaging machine applications, Schaeffler offers a wide range of robust, reliable bearings, which can all be corrosion protected, sealed and lubricated for life for continuous operation.
The Schaeffler bearing range includes deep groove ball bearings, radial insert ball bearings, plain bearings, housed units, track rollers, slewing rings and linear guidance systems. All these products are designed to fulfill several key principles, including compact design, maintenance-free operation, modular components and reliable, long operating life.
Housing units
Housing units are found in many food and beverage processing lines, from materials handling systems to conveyor belt drives, pumps and fans.
Schaeffler’s range of housing units now includes units manufactured to Japanese Industrial Standards (JIS). In terms of their boundary dimensions, mounting and lubrication, the housing units can be considered as direct replacements for many Far Eastern equivalents.
The new FAG Black Series of radial insert ball bearings and housing units from Schaeffler are robust, ready-to-fit, self-contained units that provide simplified mounting, smooth running and high reliability.
Black Series radial insert ball bearings with a spherical outer ring are based on deep groove ball bearings and are manufactured to JIS B 1558. The outer rings, inner rings and shields are coated with Durotect B – a thin matt black, mixed iron oxide layer developed by Schaeffler that provides high corrosion resistance.
Black Series housing units are manufactured to JIS B 1559. The units comprise of flake graphite cast iron housings with a spherical seating in which radial insert ball bearings are located. The units are selectively matched and are available as ‘plummer block’, flanged or take-up housing units.
When fitted in housings the spherical seating can allow for static misalignment of the shaft / assembly. The housings have a re-lubrication facility and are supplied with the appropriate grease fitting and dust cap.
In addition to the existing H7 bearing seating tolerance (i.e. light swing torque), Black Series housing units are now also available with a J7 fit (ie medium swing torque), which is in increased demand in Europe.
Schaeffler also offers housing units with corrosion-resistant (stainless) sheet steel or plastic (glass fibre reinforced PBT) housings. Plastic housings are highly resistant to moisture, UV radiation, bacterial and fungal attacks, as well as many chemical media. These bearing units are used predominantly as locating bearings, but are also suitable as non-locating bearings under low loads and speeds.
Grease selection
Selecting the correct lubricant is a critical factor in ensuring the functional reliability and optimum operating life of a rolling bearing. Failure statistics show that a significant proportion of premature rolling bearing failures are directly or indirectly related to the lubricant used. The main causes of failure here are unsuitable lubricants (20%), aged lubricants (20%) and insufficient lubrication (15%).
For food and beverage processing companies, legal and environmental factors must be considered when selecting a suitable grease. A worldwide standard that can be used is approval in accordance with the NSF (National Sanitary Foundation) H1 or H2.
A lubricant with the code H1 (food-grade lubricant) may be used where occasional, technically unavoidable contact with foodstuffs cannot be eliminated. This means that the grease must be non-toxic, rapidly broken down by the organism and neutral in terms of both odour and taste. Such lubricants often comprise aluminium complex soap thickeners and polyalphaolefins or medicinal white oils as a base oil.
H2 lubricants are intended for general use within the food processing industry where no contact with foodstuffs occurs.
Schaeffler’s ARCANOL range of lubricants includes 17 different greases, each one developed by Schaeffler application engineers and produced by leading international lubricant manufacturers. These greases therefore provide specific lubrication properties for almost every type of industrial application, including food, beverage and packaging applications.
Dr Steve Lacey is Engineering Manager at Schaeffler UK. www.schaeffler.co.uk
