Magnetic Separators and Metal Detectors at ArabPlast 2019
After a successful exhibition in 2017, Bunting Magnetics is, once again, exhibiting at the ArabPlastinternational exhibition (5-8 January 2019, Dubai World Trade Centre, Dubai, UAE). On stand 5D125, Bunting is exhibiting magnetic separators and metal detectors specifically designed for use in the plastics industry.
ArabPlast is the largest trade expo for plastics, petrochemicals and rubber industry in the MENA region. The 2017 exhibition had 906 exhibitors from 41 countries and 27,268 visitors from 119 countries.
On the stand at ArabPlast, Bunting will be displaying a wide range of equipment used to remove metal contamination from the plastics manufacturing process including:
Fully functioning quickTRON 03R Metal Detector with an FF Drawer Filter Magnet mounted on top;
At ArabPlast, the Bunting team intends to help local plastics companies solve any metal contamination problems. The team is able to draw upon their vast experience in Europe and the USA.
The Bunting team is also looking forward to helping local recycling companies address plastic waste management. They intend to share experience of working with UK plastic recyclers such as EcoVynwhere the installation of FF Drawer Grate Filters reduced waste by 94%.
“Exhibiting at overseas exhibitions is an important part of our marketing strategy,” said Dave. “It gives us the opportunity to meet local companies and learn about their market. We can also share our experiences, helping companies solve metal contamination problems, reducing waste and increasing efficiency. The Middle East and North Africa market is evolving at a rapid pace and offers great opportunities.”
For further information about metal separation equipment designed for removing metal during the plastic or plastic product manufacturing process, please visit us at ArabPlast, go to our website or contact us on:
Bunting Provide Technical Support at Two Overseas Shows
Local representative Tekemashas exhibited at two Autumn international trade shows in 2018. The equipment displayed on their stands included a selection of Magnetic Separators. Both exhibitions proved to be successful, with leads for both magnetic separation and metal detection equipment.
Tekemas is based in Rodovre, Denmark and specialises in providing solutions in the handling and processing of powders and granules. They represent a number of international equipment and technology suppliers including Wysetech Materials Handling and Matcon.
Scanpack (Gothenburg, Sweden, 23-26 October 2018)
Scanpack is an international event for the packaging industry. Exhibitors showcase solutions for the entire packaging process. Visitors included managers, marketers, brand managers and others involved in packaging, from conception and design, through to production and logistics. Representatives from companies based in over 40 countries attend the show.
Bunting’s Sales Engineer, Tom Higginbottom, attended the show.
“Overseas exhibitions provide an ideal opportunity to learn about the local markets,” Tom explained. “The time I spent with the Tekemas team has been precious. I was able to provide support with technical information and, potentially more importantly, develop my relationship with the Tekemas engineers.”
FoodTech (Herning, Denmark, 13-15 November 2018)
FoodTechis a food technology event, held every two years in MCH Messecenter Herning. The exhibition is focused on showcasing the latest technology for the food manufacturing and processing sectors.
Tekemas were supported by Bunting’s Head of Sales, Dave Hills.
“Before I had even left the United Kingdom, Tekemas had arranged meetings on the stand with prospective customers,” said Dave. “Supporting our local representatives at shows like this is so important. The time can be used for product and application training as well as developing all-important relationships. It has been a very successful show.”
Bunting and Master Magnets are continually searching for new overseas representatives in a wide range of industrial sectors. For further information, contact Dave Hills on email@example.com.
For further information on Magnetic Separators or Metal Detectors used in removing and detecting metal contamination in food, please visit our website or contact us on:
In the past 18 months, Bunting has manufactured and supplied 15 Magnetic Liquid Traps to citrus juice producers in Spain. The magnetic separators are used to capture and remove fine iron from the juice.
Need for Magnetic Separator Protection
Fine iron is commonly found in most food processes. The origin of the metal contamination is often difficult to pinpoint. Typical sources include:
When the fruit is harvested. Dirt can often have a magnetic constituent and is carried on the surface of the fruit;
During transportation. Even if the fruit is collected in plastic containers, metal contamination can be introduced from the transport (eg rust, metal dust, dirt).
When the fruit is processed. The process of extracting the juice from the orange or grapefruit involves several stages where the fruit is sliced and compressed. Wear to the process equipment will produce fine metal contamination.
Extracting the Metal Contamination
Due to the fine nature of the metal contamination, high strength magnets are required. The Bunting Magnetic Liquid Traps are fitted with Neodymium Rare Earth Tube Magnets, the strongest permanent magnets presently available.
The Magnetic Liquid Filters are designed to ensure maximum contact is made between the juice and the magnetic fields by forcing liquids through a tightly spaced grid of magnets. Ferrous contamination is magnetically extracted from the liquid flow by the extremely powerful Rare Earth magnet design and held firmly on the surface of the Tube Magnets.
Cleaning of the Tube Magnets is simple. On a designated frequency, determined by the level of contamination, the lid of the Magnetic Liquid Trap is removed. The Tube Magnets are attached to the lid and are then manually wiped clean.
Dealing With Acidity
Fruit juices are naturally acidic, ranging between 2.00 and 4.80. This level of acid has the ability to corrode standard welds. In the Magnetic Liquid Trap, the Tube Magnets are welded onto the lid. The welds are all to food grade standards.
However, if standard welding materials are used, these will pit and corrode over time. Eventually, the weld will be eaten away, allowing the ingress of liquid into the Tube Magnet casing. This catastrophically damages the magnets, causing them to swell and lose their magnetic properties. As the magnet swells, it can also split the outer casing.
“We are now regularly supplying Liquid Magnetic Traps into Spain,” explained Dave Hills, Bunting’s Head of Sales. “Our local representative has done a great job in helping the local citrus juice producers. He understands the industry and fully understands the challenges.”
For further information on Magnetic Separators used in removing metal contamination from fruit juices or for any food processing application, please visit our website or contact us on:
Magnets: Three (3) high strength Neodymium Rare Earth Magnets;, three 25mm diameter stainless steel
Dimension of the opening: 150mm square
Rows of Magnets: One
Flanges: Bottom and top included, 6.35mm thick
Slide gate: 6.35mm thick
Viewing port: Unit features a 9.5mm thick clear polycarbonate drawer front
During the manufacturing process of any plastic or plastic product, it is possible for metal to be introduced into the process. This could be from a wide variety of sources including the wear of processing machinery.
If metal contamination is not removed, it can damage processing equipment and result in increased final product rejects. The Drawer Filter Magnets are used to attract, hold and thus remove any magnetically susceptible metal contamination.
Another Export Order
“This is another great export order for Bunting,”said Hills. “Despite all the concerns about BREXIT, we continue to work hard supporting our regionally based distributors. This is paying dividends as our sales overseas continue to rise.”
For further information about metal separation equipment designed for removing metal during the plastic or plastic product manufacturing process, please visit our website or contact us on:
Bunting engineers have conducted a thorough review of all the Magnetic Separators installed at the Jordans Dorset Ryvita plant in Poole, Dorset. The audit was completed over three days, including attending site on Saturday to prevent any loss in production.
Jordans Dorset Ryvita has a strong heritage of making whole grain foods and working with farmers to protect the countryside. Ever since the brands first came together, they have continued to act on these values.
A Magnetic Separator Audit involves the inspection and test of Magnetic Separators to confirm their magnetic and physical integrity. Commonly, such tests are conducted annually, with the final report forming part of the company’s quality audit process.
The tests in a Magnetic Separator Audit are conducted in two stages. Stage one involved the inspection of the physical integrity of the Magnetic Separator. This includes checking welds, and assessing any wear and damage to the surface.
Stage two involves testing the magnetic strength of the Magnetic Separator. These tests are conducted by placed a magnetic ball or plate into the magnetic field and then measuring the force (in kgs) needed to remove that object from the surface of the magnetic separator. The actual ‘gauss’ reading of a Magnetic Separator is not checked as measurement is difficult and often inaccurate. Gauss is the is the cgs unit of measurement of magnetic flux density (or “magnetic induction”, but can be difficult to measure accurately.
The metal test piece is attached to the end of the Spring Balance and then placed into the magnetic field, being attracted to the magnetic pole. The metal test piece is then pulled off the surface of the magnetic separator whilst holding the other end of the spring balance. The amount of force needed to remove the metal test piece from the surface is recorded (in kgs). The test is repeated three times and an average reading taken. Similar techniques are used to test other designs of Magnetic Separators such as Plate Magnets.
There were a wide range of designs, strengths and ages of Magnetic Separators in the production process at Jordans Dorset Ryvita. The company had not experienced any problems due to metal contamination and requested the audit as part of their continued improvement plan.
Day one was spent assessing the location and recording the customer identity numbers of all the Magnetic Separators. Checking the location also highlighted any health and safety issues that needed to be considered for the audit, such as working at heights. The review identified 52 Magnetic Separators.
The physical checks of the Magnetic Separators were conducted on day two and three, on the weekend to minimise any production downtime. Each Magnetic Separator was removed from its location and visually inspected. Then the magnetic strength was checked using the pull test technique. The data was recorded and presented in a detailed report with recommendations following the audit. This report can then be used as part of the quality management system. It also provides base data for comparison on future audits.
Following the audit, the engineering team at Jordans Dorset Ryvita have made several changes to improve the removal of metal during the production process.
“Having an external review of the Magnetic Separators really helps the client,” explained Mark Harris, Bunting’s Engineer. “We conducted the audit without any assumptions and this freedom enabled us to highlight the areas where protection was good and also focus attention where they could be improvements. We are looking forward to working with the team at Jordans Dorset Ryvita for the long-term and providing our technical support when needed.”
For further information on measuring the strength of a Magnetic Separator, please visit our website or contact us on:
A Magnetic Separator is designed to attract, capture and hold magnetic particles. The magnetic strength needed to successfully achieve that design objective is commonly stated in a magnetic separator supplier’s quotation or specified in the tender. This ‘Magnetic Strength’ is usually referenced in terms of ‘gauss’, a unit of measurement. However, the ‘gauss’ value can be very difficult to accurately measure.
There is a more practical method of assessing the magnetic strength. This removes any ambiguity whilst providing simple, repeatable, and comparable data to assess most Magnetic Separators.
Measuring Magnetic Strength
The magnetic strength of a Magnetic Separator is often referenced in terms of ‘gauss’. Gauss(symbolized G) is the centimetre-gram-second (cgs) unit of magnetic flux density. A flux density of 1 G represents one maxwell per centimetre squared (1 Mx cm -2 ). It is named after the German scientist Carl Friedrich Gauss.
Gauss can be measured using a Gaussmeter. However, it is important to note that the Gauss rating on its own does not fully indicate the strength of a magnet. Additionally, gaussmeters can give a range of readings dependent upon the orientation of the probe and several other variable parameters.
Proposals for Tube Magnets often include details of length, diameter and the gauss reading. With the gauss reading being so difficult to test and prove, purchasers and users are unable to check that the Tube Magnets supplied actually meet the specification of the quote and the order.
However, in terms of Magnetic Separation the objective for the user is simple; the magnetic force must enable the attraction and capture of any magnetically susceptible metal. That ability can be measured as a function of the effort needed to remove a specific steel item from the surface.
Measuring the effort needed to remove a steel item from the face or surface of a Magnetic Separator is achieved using a spring balance and is commonly called a ‘Pull Test’. The magnetic test piece (e.g. a 6mm ball bearing welded onto a non-magnetic attachment ring) is clipped onto the end of the spring balance.
The magnetic test piece is placed on the surface of the Magnetic Separator and force applied at the other end of the spring balance until it is detached. The force required to remove the magnetic test piece (measured in kgs) is recorded on the measurement scale of the spring balance.
Measurements are taken in the centre of the Tube Magnet and on the end poles. They are repeated three times and the average recorded as the force required to remove the magnetic test piece at each point.
The following video explains the Pull Test technique.
This simple but effective method does not record or provide any indication of the gauss, but accurately provides data that can be used to compare the condition of a Magnetic Separator over time and compare the performance with other similar designs.
Pull Test Experiments
Magnetic Separator designs vary considerably depending on the application. The Pull Test technique is suitable for measuring the magnetic strength of smaller Magnetic Separators such as Tube or Cartridge Magnets and Plate Magnets.
Tube or Cartridge Magnets are often used stand alone or as part of a Magnetic Separator configuration (e.g. Drawer Filter or Liquid Trap).
A small steel ball is used as the magnetic test piece when measuring the magnetic strength of a Tube or Cartridge Magnet (the photograph shows a 6mm diameter ball)
The metal test piece is attached to the end of the Spring Balance and then placed into the magnetic field, being attracted to the magnetic pole.
In a series of experiments, we used the Pull Test technique to assess the magnetic strength of Tube Magnets with Ceramic (Ferrite), Standard Neodymium Rare Earth, and High Strength Neodymium Rare Earth Magnets.
The tests were undertaken using three different sizes of steel ball in the magnetic test piece (6mm, 12mm and 25mm) and introduced non-magnetic spacer to assess the magnetic strength at specific distances away from the surface (3mm and 6mm). All the recorded measurements are in kilograms (kg)
Note: all measurements are recorded in kilogrammes.
Standard Neodymium Rare Earth
Note: all measurements are recorded in kilogrammes.
High Strength Neodymium Rare Earth
Note: all measurements are recorded in kilogrammes.
In all cases, the drop off in magnetic strength as you move away from the surface of the Tube Magnet is significant and this highlights the need for metal contamination to come into contact with the surface. Arrangements where the Tube Magnets are configured as a Grate (i.e. are lined up and equally spaced) commonly have a deflector above the gap between the Tubes that directs material in the area of maximum magnetic strength.
The tests highlight the difference in magnetic strength on the surface, with high strength Rare Earth magnets producing nearly 3 times as much pull as Ceramic magnets.
Findings During Magnetic Separator Audits
Magnetic Separator Audits often highlight issues that had previously gone undetected. The first check focuses on the physical integrity of the Magnetic Separator, inspecting welds, and assessing wear and damage. Once these have been completed, the measurements are taken.
The most common findings when undertaking magnetic separator audits are:
Magnetic Liquid Filters, fitted into pipelines, have Tube Magnets that are welded to a lid and project down into the product flow. Metal is attracted and captured on the surface of the Tube Magnet.
In cases where the welds have failed (e.g. poor manufacture, eaten away by acidic or alkaline liquids), liquid will seep into the tube and onto the magnets. The magnets then swell and lose magnetic strength, ultimately splitting the outer stainless-steel casing.
Tube Magnet Wear
When material falls directly onto the surface of a Tube Magnet, over time the surface can be worn. Wear usually occurs on the poles where magnetic particles have been captured. Once the outer stainless-steel casing has been breached, the Tube Magnet should be replaced.
Weak Tube Magnets
Magnetic separation audits highlight the variance in magnetic strength of Tube Magnets. Often, the Tube Magnets have been installed for some time and details of the original specification have been lost. When testing the magnetic strength, some Tube Magnets are found to have very poor strength and provide little if no metal separation protection. This is of great concern when the Tube Magnet is positioned to protect a particular item of processing plant where metal contamination damage could result in production downtime and costly repairs.
The Pull Test Experiments highlights the importance of physically checking the real magnetic strength of a Tube Magnet and not only replying on the stated gauss. Including details of the force needed to detach a 6mm steel ball from the surface of the Tube Magnet in the request for quotation and the order, protects the user and ensures that the supplied equipment is as exactly as stated.
This ‘Pull Test’ measurement technique also enables a regular comparative test that will immediately highlight any drop in magnetic strength. This can be used in annual audits or inspections as part of a plant’s quality management system. A change in ‘pull’ strength may be the result of physical (e.g. failed weld, broken magnets from being dropped) or excessive heat. The reduced magnetic force may result in the magnetic separator no longer being fit for purpose.
For further information on measuring the strength of a Magnetic Separator, please visit our website or contact us on:
The theme of the 2018 Recycle Week (24-30 September) is ‘Recycling. We do. Because it matters.’ Recycle Week is a celebration of recycling, organised by WRAP under the ‘Recycle Now‘ brand.
Recycling has never been more prominent in the news, with managing plastic waste high on the agenda. We work with many plastic recycling companies and have provided many magnetic separators and metal detectors to remove metal contamination. To celebrate Recycle Week we wanted to talk about plastics recycling success and also highlight the changes faced by companies recycling plastic.
EcoVyn Ltd is at the forefront of PVC compounding and brings pioneering new technology to the market place. They offer one of the most advanced and innovative production processes in the UK producing reprocessed, blended and virgin compounds for a variety of applications. By installing Drawer Magnet Filters, EcoVyn reduced their waste by 94%.
A French plastic recycling company installed the Drawer Magnets to remove fine iron contamination present in the recovered and granulated plastic. If the metal is left in the reclaimed plastic, it causes serious defects in the new plastic product and can also damage processing equipment.
A new plastics recycling plant was built in Kent, UK. The plant was designed to handle up to 25 tonnes per hour of reclaimed plastic. Once shredded, the plastic is passed over a strong Drum Magnet (to remove small ferrous metals) followed by an Eddy Current Separator (to remove non-ferrous metals). The end product is also passed through a Quicktron Metal Detector prior to the clean plastic being bagged ready for shipment.
We work with many plastic recycling companies located across the world. Every company is faced with the problem of contamination. Contaminated plastic waste is worthless and processing is required to remove contaminants, such as metal and stone, to make this waste product reusable.
We are fortunate to be working with some amazing companies in the waste and recycling sector. Their innovation and knowledge continually increases the amount of materials we can recycle and reuse.
For further information metal separation equipment designed for removing metal from plastic waste and in other recycling applications, please visit our website or contact us on:
At this year’s rejuvenated RWM Exhibition (NEC, Birmingham, 12th – 13th September), the Bunting Magnetics and Master Magnets stand proved to be a great success. Being positioned in a prime stand in front of the entrance, and with working metal separators on the stand, visitors were drawn to see the latest developments in magnetic separation technology.
At an event in the Google headquarters in London, RWM exhibition manager Nick Woore announced their intention to inject new life into the show. The plans sounded positive, although there was still a great deal of doubt from many exhibitors. In fact, in 2018 the number of exhibitors were lower than in 2017, but visitors numbers were higher.
“It was great to see people queuing outside the entrance on the first morning of the exhibition,” said Dave Hills, Bunting’s Head of Sales. “As soon as the doors opened, our stand was full of visitors.”
Bunting had two operating production-sized metal separators on the stand:
Dave Hills also gave two presentations on ‘Stainless Steel Separation in Modern Day Recycling’.
“Being able to show visitors the separation capabilities of the equipment was vitally important,” explained Hills. “This made it easier to relate to their metal separation requirements. Following the exhibition we will be conducting tests at our Master Magnets Redditch laboratory, where we can confirm the separation capabilities. It is going to be a busy few months.”
Hills also explained the importance of a successful RWM. “Recycling and good waste management is no longer an option but a necessity and it is essential that there is a UK based trade event. We are looking forward to hearing how the organisers plan to further develop RWM for 2019.”
Metal enters the food manufacturing process via many different avenues. Metal can be present in ingredients being delivered to a food processing plant and unless removed at source can enter the process and cause significant damage. Equipment failure and wear can also lead to metal contamination and is usually removed with the right combination of magnetic separators and metal detectors.
The source of the metal contamination in the granulated sugar is presently unknown and an investigation is most likely underway. The sugar is sold in the UK by the retailers Iceland, Poundland, and Sainsbury’s and has been recalled. The metal contamination will be costly in terms of direct financial cost and reputation.
Getting Metal Out of Sugar
Removing metal contamination from granulated sugar is commonly achieved using Drawer Filter Magnets and Plate Magnets. Plate Magnets are installed in chutes where the sugar flows over the surface. Due to the small size of the sugar granules Neodymium Rare Earth Plate Magnets are preferable, producing the highest magnetic attractive force to remove small ferrous and magnetically-susceptible work-hardened stainless steel.
Due to the potential sticky nature of the sugar, sleeved Drawer Filter Magnets are often preferred, in an easy-clean design. The Rare Earth Tube Magnet sits tightly inside a fixed stainless steel outer tube. Cleaning forms part of a daily maintenance schedule, with the Tube Magnets being withdrawn from the sleeves to drag and deposit metal contamination in a discharge chute.
Magnetic Separation Audits
Bunting engineers conduct regular Magnetic Separation Audits at many food manufacturing plants. An audit involves the visual and physical inspection of every magnetic separator in a plant to check on the location, suitability integrity (ie checking welds and for wear), and magnetic strength (which can deteriorate with excessive heat, weld damage, or if dropped). In April three Magnetic Audits were conducted and highlighted a number of issues that have since been addressed.
For more information on preventing Metal Contamination Food Safety Scares, or to arrange a free onsite survey and audit of a particular plant or process, please contact the Bunting team on:
Metal Recovery Equipment on Show at CARS Exhibition
At the CARS 2018 exhibition (11-12 July 2018, NAEC, Stoneleigh, UK), the focus on stand M6 will be on maximising the recovery of metal whilst also maintaining purity levels.
The Complete Auto Recycling Show (CARS) is Europe’s premier event for auto recyclers and material processors. It is the only event of its kind, drawing over 1,200 attendees from across the globe in 2016.
Unlike traditional trade shows, visitors get the chance to experience not only the indoor exhibitions, but to see working line demonstrations, participate in offsite tours, visit the Skills Lab and access the Conference Theatre – all included within the free ticket.
“Our focus is on recovering as much metal as possible in a high value grade,” explained Dave Hills, Bunting and Master Magnets Head of Sales. “There is always a balance between recovery and purity and the best results often come from several stages of separation.”
Master Magnets has a complete range of metal separation equipment for every stage of metal recovery.
Ferrous Metal Separation
The primary metal separation stage in any recycling plant focused on ferrous metals. Large Drum Magnets, specifically designed for the arduous environment, are commonly used along with smaller Drum Magnets and Pulley Magnets.
Non Ferrous Metal Recovery
Eddy Current Separator designs have been perfected to enable the recovery of even the smallest non-ferrous metals. Two rotor configurations (ie concentric or eccentric) are available to suit the specific application. Recent developments include a precise splitter positioning system to maximise recovery and purity.
Stainless Steel Separation
Stainless Steel Magnetic Separators are a relatively new addition to the metal separation range of equipment that has been extremely popular in USA secondary metal processing plants. There are two variations available:
HISC (High Intensity Separation Conveyor) – This enables the magnetic separation of small and mid-sized stainless steel – 10mm to 40mm (½” to 1½”) – and for wire-cleaning applications.
SSSC (Stainless Steel Separation Conveyor) – With a patent magnetic circuit design of high-intensity neodymium magnets, the SSSC can remove up to 94% of irregular shaped stainless steel – up to 125mm (5”) in size – from auto shredding or wire chopping stream.
On stand M6 at the CARS exhibition there will be demonstrations of both non-ferrous metal recovery on an Eddy Current Separator and Stainless Steel separation.
For further information on Bunting Magnetics and Master Magnets and our range of metal separation equipment designed for the metal recycling, please visit our websites or contact us on: