Services Required By Plastic Manufacturers

Energy Management

Providers of these services help to ensure that a production facility is not wasting valuable resources. For example, a compressed air ring-main will commonly have multiple leaks, adding additional load to compressors and adding costs relating to maintenance and power consumption. Sensitive equipment can be used to detect leaks from a distance, allowing them to be readily fixed.

On-site surveys with thermal imaging equipment can also highlight heat losses. For example, in a plastic processing facility, large amounts of thermal energy are required to reduce polymers to a molten state. Heater bands are fitted to plasticising units to help to achieve this, but without the correct insulation, much of the thermal energy generated will be lost to the surrounding environment.

Visit here to contact the leading UK companies that can provide you with advice and quotes for your Energy Management requirements.

Material Testing & Flow Analysis

Third party material testing can avoid the need to purchase expensive testing equipment. Below are some examples of the types of testing services that are relevant to the plastics sector:

• MFI Testing. This is used to establish the Melt Flow Index of a material batch. The MFI of a material affects both its ability to flow (higher MFI = lower viscosity) and its’ impact resistance (Lower MFI materials are tougher and less brittle).
• Colour Measurement. Equipment such as Colorimeters are used to eliminate human subjectivity, i.e. they determine colour consistency. Spectrophotometers provide more accurate results, by eliminating the effect of factors such as surface finish. (Gloss meters are also utilised if surface finish needs to be accurately determined).
• Impact Testing. Impact Testing is used to simulate how a plastic component will perform when subjected to everyday use. For example, refuse bins are frequently drop tested (literally dropped onto a hard surface from a set height) to ensure that they will cope with being pulled down a curb.
  Testing in a ‘laboratory’ involves a small sample of plastic being subjected to either a dropped weight or impact from a pendulum.
• Mechanical Testing. Mechanical Testing is performed using a piece of equipment that subjects a sample to a set amount of load, e.g. by stretching it. Equipment is in a wide range of sizes to accommodate larger samples or increased levels of force. Typical measurements taken can relate to:
• Tensile properties. These include ‘break testing’, i.e. the load per unit of area required to cause failure, as well as stretching characteristics. For example, the modulus of elasticity is a measurement of how far a component can be stretched before it is permanently deformed, (the ‘yield’ point), i.e. it no longer returns to its original state.
• Compression testing is similar to above but involves ‘squashing’ a sample of material until it permanently deforms and eventually fractures.
• Bend Testing. This is used if a product is required to be able to flex a set amount without deforming or failing.
• Peel and Tear testing. This is a way of determining when a product will ‘part’ under load. It is often used for items that are woven from plastic fibres.

Visit here to contact the leading UK companies that can provide you with advice and quotes for your Material Testing & Analysis requirements.

Mould Flow Analysis is a technique that uses sophisticated software to simulate how the material will fill an injection mould tool. By importing a 3D design of the component, it is possible to simulate how changes to the moulding process will affect final part quality.

Factors such as melt temperature, mould temperature, injection pressure etc. can be analysed in order to achieve optimum results. Further improvements can be made through changes to the position, size and number of material injection points, as well as altering component features, wall thicknesses, etc.

Once the process and tool design have been optimised, production of the actual mould tool can commence.

Visit here to contact the leading UK companies that can provide you with advice and quotes for your Moulding Simulation & Flow Analysis requirements.

Measurement (Metrology)

As well as physically measure one or more components using equipment such as CMM (coordinate measuring machines) or vision systems, companies can provide third-party support for new product development. Typical services include:

• Initial sample inspection reports (ISIR) and Capability (CAP) Studies. These look at how a product’s tolerances vary.
• Tool validation metrology
• Multi-cavity inspection reports. This is to make sure that different moulding cavities within a tool are all within tolerance.
• Reverse engineering. Used to produce detailed product drawings if they aren’t available i.e. by accurately measuring an existing component.
• Cavity verification / CAD-to-part deviation
• Gauge R&R (repeatability and reproducibility) studies to ensure measurements taken with your own in-house measuring equipment are repeatable.

Visit here to contact the leading UK companies that can provide you with advice and quotes for your Metrology requirements.

Oil Management & Filtration

Despite the introduction of all-electric technology, the majority of production equipment used for moulding plastic components still uses hydraulic systems to produce linear and rotary movements. This requires the use of hydraulic oil, and grades are available that are designed for this application.

The hydraulic oil is subjected to both extreme pressure and heat, causing it to degrade over a period of time, making it less effective in terms of component lubrication. The production of particulates can also cause wear to metal components such as hydraulic rams and associated seals, as well as cause control valves to fail.

Typical services provided by specialists in oil management and filtration include:

• Initial equipment oil-fill and flushing. When equipment such as injection moulding machines are delivered to a production site, they are not permitted to contain hydraulic oil, i.e. to avoid the risk of spillage and environmental contamination.
  Once fully assembled, the oil tank of the machine can be filled. This should not be done by the plastic manufacturing company unless they have the correct equipment and suitably trained staff. This is because:
• Even a brand-new machine may contain metal particles that have been produced during the fabrication of component parts. These will need flushing out, this being achieved by filling the machine and circulating oil around its systems via an external filtering system. This ‘rig’ may remain in place for 24 hours or more.
• An unopened drum of oil should not be presumed to be free of contamination, e.g. resulting from the manufacture of the drum.
• Filtering needs to be down to the ‘micron’ level, as even small particles of metal can clog and damage hydraulic valves and cause the abrasion of flexible seals.
• Ongoing oil maintenance. Depending on the manufacturing process involved, the serviceable life of hydraulic oil will vary. For example, an injection moulding machine producing thin-walled packaging products will be ‘cycling’ very quickly, so there will be higher loading on the oil in terms of both pressurisation and heat exposure.
  Oil management companies can take regular samples from the machine’s tanks and analyse them. This will monitor several potential issues:
• Particulates resulting from degradation of the oil itself, or resulting from wear to the components of a machine that can produce a suspension of metallic particles.
• General degradation of the oil that will reduce its performance and potentially risk damage to the machine.
• Water contamination, e.g. due to damage to the machines heat exchange system.

Depending on results, the existing oil may need to be re-filtered, or replaced in its entirety. In the latter case, the machines oil tank may be inspected and cleaned prior to re-filling the machine.

Visit here to contact the leading UK companies that can provide you with advice and quotes for your Oil Management requirements.

Pipework Installation

Within a typical plastics factory, there will be several ‘circuits’ of pipework, each providing a key service. There are specialist companies that can install this pipework and any associated control valves and distribution manifolds.

Examples of pipe circuits include:

• Plastic Raw Material. Larger factories may have a central material handling system that performs functions such as transferring plastic granules from bulk storage (e.g. silos) to production equipment, or from drying stations to the relevant machine. Pipework is typically made from stainless steel, as this is strong, can be shaped into complex curves (sharp corners must be avoided), is hygienic and naturally resistant to abrasive fillers.
• Compressed Air. This may be required for robotic vacuum circuits, or to power pneumatic cylinders, such as those used to open the large doors of injection moulding machines.
• Chilled Water. A typical plastics factory will require chilled water. This is usually provided by a large chiller or air blast type cooler (in its own area of the factory or outside the premises). A water ring main with a flow and return circuit will distribute the cooled water.
  In some cases, there may be two separate water ring mains. This is because a factory (particularly is specialising in injection moulding) will have two requirements for chilled water.
• To cool hydraulic circuits with heat exchangers. Water temperature does not need to be particularly low, so sometimes an outdoor air blast type system will suffice. This negates the need for an expensive (particularly in terms of energy costs) refrigerant type chiller.
• To cool production tooling. In this case, temperatures will need to be significantly below ambient levels, so a dedicated refrigerant type chiller will be required.

Visit here to contact the leading UK companies that can provide you with advice and quotes for your Pipework requirements.

Plastic Part Plating, Painting & Decoration

As well as adding colour to plastic components through the addition of masterbatch to the base material, components can be ‘enhanced’ once manufactured.

Plating of plastic components involves a multi-stage electroplating process that results in a ‘chrome’ type finish. In the majority of cases, ABS (or a blend of ABS and Polycarbonate) will be the plastic polymer involved. The plating will not directly adhere to the plastic surface, so a metallic intermediate layer is first applied (typically nickel) by ‘dipping’ the components.

Typical stages of the process are cleaning>acid etching the plastic’s surface in order to create a ‘key’>neutralisation of the acid>dipping to create the intermediate metallic layer>adding the final finish using electroplating.

Vacuum Metallising of plastic components involves the deposition of a thin metallic layer onto the plastic’s surface. The process requires a pure metal sample (such as copper, chrome or zinc) to be vapourised within a vacuum chamber.

Once deposited, the resulting layer is highly reflective, making it ideal for components such as headlight reflectors. The surface is also conductive, making it a good choice for electronic applications.

Painting plastic parts can involve a highly automated process. In large-scale applications, there may be as many as 50 stations involved. A moving track system carries the plastic components through the stations, with an open-ended oven forming part of the system.

Parts are first ionised, providing them with an electrically charged surface to which the oppositely charged paint particles are attracted. Even when surfaces are uneven, this method can achieve a very even distribution of paint.

6-Axis robots are now commonly used to dispense the various layers of paints and clear protective finishes.

Visit here to contact the leading UK companies that can provide you with advice and quotes for your Plating, Painting & Part Decoration requirements.

Production Monitoring

By fitting sensors and switches to plastic production equipment, a sophisticated software package can provide real-time information on the status of multiple jobs. A display screen can illustrate the status of each job, i.e. if it is on schedule, behind or ahead of schedule etc. Also, an indication of the machine status is provided, e.g. ‘down’ for material or maintenance issues, undergoing tool-change etc.

These systems can ‘tie-in’ with other aspects of a company’s activities, for example:

• Scheduling maintenance
• Highlighting the need for increased manufacturing capacity
• Indicating that a particular material grade is in short supply
• Scheduling of transport to the customer

Prototyping & Rapid Tooling

Larger injection moulding projects frequently employ plastic prototyping and rapid tooling services. For example, a new packaging project may result in several multi-impression production tools running in conjunction, so getting a design wrong could prove to be expensive.

Once a product has been designed, producing visual prototypes using techniques such as 3-D printing will highlight any obvious potential issues. It is, however, only when products are produced using the correct materials and processes that a true ‘real-life’ evaluation can take place.

Low volume tooling can be manufactured from easy to machine metals such as Aluminium. These won’t have a long service life, but will allow sample mouldings to be produced. Once the design has been tweaked, perhaps using a series of Aluminium single-cavity tools, a fully hardened multi-impression tool can be manufactured with a high degree of confidence.

Visit here to contact the leading UK companies that can provide you with advice and quotes for your Prototyping & Rapid Tooling requirements

Water Treatment

Plastic processing facilities require large volumes of chilled water. This requires the installation of pipework to distribute the water, as well as cooling devices, some of which rely on the evaporation process to dissipate heat.

These water systems require the addition of various additives, as well as frequent monitoring.

• Anti-microbials (Biocides). If a water system is not completely sealed, for example, if the water is sprayed within a cooling tower, there is a risk of microbial development, including dangerous strains of bacteria such as Legionella. Specialist companies carry out frequent checks by sampling the water in circulation and ensuring that the correct water treatment procedures are in place to negate microbial growth.
• Anti-Freeze addition. In colder conditions, water can freeze and cause damage to pipework and equipment. By adding Glycol, the freezing temperature of the water can be lowered. However, if incorrectly managed, Glycol at too high a concentration can become damaging to metallic surfaces and possibly promote microbial growth.
• Additives to prevent the build-up of limescale. Limescale is a particular problem in hard water areas. Water in a factory’s ring-main is warmed as it removes heat from machinery and tooling, causing limescale to be released. As the water circulates around the system, it will sometimes slow, e.g. when passing around a bend. This can cause particles of limescale to be deposited, which can lead to a build-up that can eventually form a blockage. Chemicals can be added at a set level to inhibit the deposition of limescale.

Accreditation & Quality Control

Within a plastics manufacturing environment, it is important that strict quality management procedures are in place. There are however other measurable standards that can be required and implemented. The companies in this category are specialists in implementation and assessment of these standards.

ISO9001:2015 – This is the most common form of quality management system used in any manufacturing environment. It is an international standard, the latest edition of which was launched in 2015. All manufacturing partners on the PlastikCity site are required to work to this standard as a minimum.

ISO14001 – This is the international standard that specifies requirements for an effective environmental management system. Companies holding this accreditation are required to show an ongoing commitment to protecting the environment, e.g. through a reduction in energy consumption.

IATF16949 – This is a more stringent quality system based on ISO9001. It is designed to meet the higher quality standards required within the automotive sector.

CE Marking and Accreditation – When a manufacturing company purchases an item of equipment, it usually has to comply to EU safety standards. This is verified through the addition of a CE mark to the product by the product OEM signifying that these safety standards have been met.

If however, any amendments or additions are made to the equipment, e.g. by the plastic processing company or another equipment supplier, then the CE compliance must be reviewed. A good example would be the addition of an automation cell to an injection moulding machine.

CE Accreditation can be performed in a number of ways.

• The supplier of additional equipment may be able to perform this service providing they have suitably qualified personnel.
• With suitable training, an appointed member of the plastic processors staff can carry out and document the assessment and compliance.
• A third-party specialist can be employed to carry out this service

Toll Granulation

Toll Granulation is a service where the customer (e.g. injection moulder or extrusion company) retains ownership of the material. Our partners in the Toll Granulation section will take your waste and scrap plastic, reprocess it and then return it to you in granular form to be reused on your machinery.