Mould maintenance

Resistance to corrosion results in lower mould maintenance cost and a clean surface after the hardening process. 

Mould release agents and processing additives are engineered to improve the production process and product quality. They facilitate optimum demoulding of the contents from the mould and the release agent should not transfer from the mould surface to the moulded part. Parts that are easily removed from the mould exhibit an attractive mirror-like finish and with less mould maintenance and wear, less cleaning of the part is required. 

L - cost of mould maintenance (generally 5% of mould price), %/year M - interest on mould price (currently approximately 20%), %/year... 

Matching Temperature Control Units and Mould Maintenance... 

Ford Focus is injection moulded from HPP30GR20BK, a glass fibre reinforced polypropylene allowing a zero-maintenance engine air filter. 

Sticking to mould. Dirty mould, inadequate lubricant and undercure. Frequent cleaning and proper maintenance of moulds and proper application of mould lubricant. 

On the moulding side, a basic distinction is made between permanent and lost moulds. Foundries casting in permanent moulds, buy these metal moulds (dies) externally, but typically operate an in-house mould repair and maintenance shop. Foundries casting in lost moulds, often buy wooden, metal or plastic patterns (for their mould design) and operate an in-house pattern maintenance and repair shop. Moulds, cores and lost models are generally produced as part of the foundry process. 

Permanent moulds (or dies) are generally not made in the foundry, although die-casting foundries do have a workshop for die assembly, maintenance and repair. This type of operation, however, does not generate any environmental effects. 

Figure 3.10 All maintenance and setting operations on moulds and mould-carriers can be executed off-line, in a dedicated service station that performs all the line s movements and operative functions.

The main problem comes from the dry chopped glass that - leaving the nose of the head still not wet - flies everywhere near the mould surface. This results in negative effects on workers, on cleaning and maintenance operations, and on part quality. This problem can seriously hinder the application of this technology. 

Economics Materials costs Cost of capital plant moulds, and processing machines Speed of production Number of mouldings/units required Operating costs of component, including maintenance and fuel consumption... 

The customer rightly expects that the product ordered will be delivered in accordance to schedule, at the agreed price and to the agreed specification. To achieve this, and to strive to exceed expectations, it is essential that an effective quality system be in place. The requirements of ISO 9001 [1] form a sound basis upon which to operate. Intelligent interpretation of the component specification and dedication to its maintenance provide the injection moulding company with that rock on which a successful business may be built. Automotive companies have individually adapted ISO 9001 to produce their own standards. More recently a new standard, ISO/TS 16949 [2], has been introduced in an effort to provide harmonised quality systems within the automotive supply chain, resulting in a focused and consistent approach that could be adopted by all automotive manufacturers. 

An important aspect of the maintenance of an injection moulding machine is a regular check on the condition of the platen surfaces. Platens can become distorted due to mistakes made whilst moulds are being fitted or through excess pressure being applied to a mould that has a smaller surface area than usual. A platen that is not perfectly flat must be removed and reground or replaced since it will distort the mould and endanger future production. 

Maintenance can be scheduled on a time basis or, more accurately, on the basis of the number of mouldings produced. The latter more accurately reflects the wear on the machine. Injection moulding machines can be equipped with shot meters to facilitate this type of maintenance cycle. Software is available to support and monitor routine maintenance in the injection moulding industry. 

A practical route to reduce the effects of photo-degradation in PUs (as in the case of other polymers) is the addition of suitable light stabilizers by different ways. The most used procedure is the additive stabilization method. A more effective method to increase the maintenance of the stabilizer in the polymer is the chemical bonding of these compounds to the macromolecular chain even in the course of polyurethane synthesis. Some attempts to introduce in such way the stabilizers in polymers are known. Thus, a benzotriazole UV absorber was mixed with a prepolymer containing isocyanate groups and the chain extender directly into moulding machine (cone. 0.5%) [64, 323]. The stabilizer can be also mixed into polyol component before its reaction with the isocyanate component. The stabilizer that usually contains OH groups could form chemical bonds with the macromolecular chain in some extent [324]. 

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