Loma Services > X-ray Inspection > Guide to X-ray
X-ray inspection systems are fast becoming a common feature of food processing plants throughout the world. The advantages that X-ray Inspection has over traditional metal detection and checkweighing systems make them essential pieces of equipment for many companies.
In order to help you learn more about this remarkable technology, read the following Loma Guide to X-ray Inspection.
Why X-ray inspection?
X-ray inspection performance
Loma in X-ray
Principles of X-ray inspection
Frequently-asked questions
Why X-ray inspection?
Brand recognition and HACCP programmes are becoming increasingly important in the food industry. Today, consumers and retailers are better informed and more focused on purchasing quality products. A contamination issue can impact on the brand image and long-term success of a business.
HACCP programmes can help prevent contamination, provided the proper technology and processes are in place.
Loma is committed to providing the online contaminant detection equipment required of many HACCP programmes to protect your brand image and help your company win more business in the future.
There are three key reasons for investing in X-ray inspection:
- The business benefits of better quality and greater confidence in compliance
- The technical and marketing advantages of better metal detection and detection on non-metallic contaminants
- The operational advantages of maximum inspection performance at high line speeds with reliability and online simplicity
Business case
Protecting consumers, brand image, integrity and ensuring quality and compliance represents a significant cost to your business. With Loma X-ray inspection solutions, you can improve quality and reduce overall compliance costs. You also have the opportunity to increase market share and revenue.
- Ensures compliance with HACCP and retailer quality standards
- Demonstrates due diligence
- Reduces recall costs
- Avoids litigation
- Increases market share through customer confidence
- Improves customer satisfaction and retention
- Wins new business where assured quality and compliance with the latest Codes of Practice is a key customer requirement
Technical advantages
Loma X-ray inspection systems detect metal contaminants better than metal detectors and detect non-metallic contaminants, as well as missing, underweight or broken products.
- Metal detection is not affected by foil or metallic packaging
- Excellent stainless steel detection
- Immune to environmental effects
- Detects non-metallic components such as glass, stone, calcified bone, plastics, rubber, ceramic, cement, pvc, tfe
- Identifies missing product and low fill and broken product
Operational advantages
Loma X-ray inspection systems ensure 100% confidence of compliance, without stopping the production line. The systems are simple to use and support high production line speeds.
- Production line speeds in excess of 600 pack per minute or 90m/min (300 ft/min)
- Dynamic analysis maximises performance and virtually eliminates false rejects
- High speed computer maximises throughput
- Simple touch screen Windows interface designed for ease of use
- Minimal training and product learn requirement
- Increased operational flexibility with minimal set-up and changeover times
- Ability to deal with product density variations and inspect randomly- produced products on a production run
X-ray inspection performance
Detection capability
X-ray systems can detect the following non-exhaustive list of contaminants:
- Metal
- Non-ferrous metals in foil, including stainless steel
- Glass
- Stones
- Bones (only calcified)
- PVC plastic
- TFE (Teflon) plastic
- Ceramic or concrete
- Flavour/sugar clumps
- Missing product
Limitations
In most food-based products X-ray systems cannot detect the following materials
- Low-density plastics
- Thin glass, such as fluorescent tubes
- Low-density stones
- Insects
- Wood
- Hair
- Cardboard
- Paper
Applications
X-ray systems are particularly suitable for quality control in the following sectors:
- Ready meals
- Prepared foods
- Meat
- Bakery products
- Cereals
- Dairy foods
- Confectionery
- Vegetables
- Fruit
- Cosmetics
Loma in X-ray
Global food inspection capability
- Loma is a world leader in the manufacture of metal detectors, X-ray and checkweighing systems
- 95% of Loma’s systems are sold to the food and packaging industry
- Loma has more than 30 years' experience in food and packaging industry inspection
- Loma systems are used by 35 of the world’s largest 40 food companies
- Loma systems are installed in over 60 countries around the world
Advanced technology
- Loma X-ray systems utilise the same design concepts that make our metal detectors the choice of the world's largest food companies
- Loma systems are highly sensitive to both metallic and non-metallic contaminants
- Loma systems feature advanced image processing
- Loma systems incorporate sophisticated sensor technology and detection software
Comprehensive support
- Loma's International Service and Support network offers high-quality service and rapid response anywhere in the world
- Remote diagnostics are available via a modem connection
- Dedicated X-ray specialists provide advice and guidance to help you meet compliance requirements or plan a new inspection system
- We offer a systems integration service to help you link X-ray inspection systems, processing equipment and management information systems into a single integrated solution
- A range of flexible support packages can be tailored to your operating requirements, reducing downtime and ensuring systems operate at maximum efficiency
Principles of X-ray inspection
How X-rays work
Key components - An X-ray system has three main components:
- Device to generate X-rays
- Sensor to detect contaminants
- High-speed computer to process sensor data
Process
- X-rays are generated by a special glass tube that is cooled
- When high voltage is applied to the tube, electrons are generated
- The electrons strike a target which emits a stream of X-rays that are focused and reduced to a fan beam
- The fan beam passes through the product before entering a sensor
- The sensor converts the X-ray signal into a form where it can be passed to a computer for processing and detection
Detection
- X-ray systems detect contaminants by density difference
- As an X-ray penetrates a product, it loses some of its energy
- A dense area such as a contaminant will reduce the energy even further
- As the X-ray exits the product, it reaches the sensor - an array of photo-diodes that precisely measure the X-ray energy that reaches them
- The sensor converts the energy signal into a grey scale image
- A high-speed computer scans the sensor at thousands of times per second and stores the individual signals
- It compares them to a dynamic value that delivers the maximum level of sensitivity and minimum level of false readings
- A contaminant is highlighted as a darker shade of grey than the product
- Effective X-ray inspection depends on the sophistication of data analysis
Safety issues
- X-ray inspection systems only generate X-rays when power is applied
- They do not use radioactive sources that require controlled disposal
- X-ray systems do not make the product radioactive
- The amount of dosage a food product is governed by strict controls. Loma systems operate at around one millionth of the current limit
- Environmental emissions from Loma systems are less than one third of naturally-occurring background radiation, and are designed to meet International Cabinet X-Ray Regulations (21CFR102.40 US)
Frequently asked questions
Technology adoption
Q. Is X-ray inspection a commercially-acceptable solution?
A. Early X-ray systems had reliability problems and were very expensive. However, the involvement of mainstream food inspection specialists like Loma ensures that new-generation X-ray systems are as robust and reliable as conventional metal detectors.
Financial
Q. X-ray systems cost more than metal detectors. Why should I pay more to do the same job?
A. In terms of contaminant detection, X-ray systems do a much better job. They can detect a wide range of non-metallic contaminants, as well as metal. However, there are other financial considerations which should be taken into account. An X-ray system reduces recall costs and minimises the risk of lost customers. It also gives you the opportunity to win new business and increase market share in applications where quality is critical.
Technical
Q. Can an X-ray system detect any contaminant?
A. No, there are limitations. If you select X-ray performance, you can find out what can and cannot be detected.
Product-related
Q. Are X-ray systems suitable for products with a variable density, such as a wedge of cheese or chicken fillets?
A. Loma's image processing software is designed to adapt to differences in product density, while maximising sensitivity. This overcomes the problems associated with conventional systems.
Production line
Q. If I introduce X-ray inspection, will I have to run my line at a slower speed?
A. No Loma X-ray systems are designed to operate continuously at speeds in excess of 600ppm or 90m/min (300ft/min)
Q. Will I need to employ specially-trained operators?
A. No, Loma systems require minimal training.
Health and safety
Q. Do I need to take special precautions to protect staff against radiation?
A. No, emission levels are less than one third of naturally-occurring background radiation.
Q. Do I have to keep documentation regarding emissions?
A. All Loma machines comply with national emission and safety regulations. When the machine is first installed a documented examination takes place. However, for peace of mind, a periodic examination is advisable. As this is a relatively simple process it can be done each day without the need to stop the production line.
Q. Will my products be contaminated by X-ray systems?
A. No, the amount of dosage a food product can be subjected to is governed by controls. Loma systems operate at around one millionth of the current limit.
