Tunnel sprues

These products may be moulded using an HR and CR system with tunnel sprue. This system, however, is not economic for mass production. Consequently an HR system with... 

If standards are used in areas subjected to wear, the maintenance costs are significantly reduced. In Figure 5.41, sprue bushings and tunnel gate inserts are shown as an example of parts with high stress and associated high wear. They are available from stock, save stocking up in-house, and thereby help reduce costs. 

FiGURE 5.41 Standards for tunnel gate and sprue bushing [1]... 

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