What problems should be paid attention to in the molding process of rolling products?

From the heating way of rolling machine,there are only two categories commonly used at present,direct fire and hot box heating.Production of large products with direct fire heating,that is,direct fire heating swing roller molding machine;The production of small and medium-sized products mostly adopts hot box heating,the more common models are hot box heating swing type roller molding machine,hot box heating 2 arm shuttle type roller molding machine,3-4 arm tower type roller molding machine,hot box heating'clam'type roller molding machine has developed rapidly in recent years.Roll molding is also known as rotary molding,rotary casting molding.The invention relates to a hollow forming method for thermoplastic plastics.

That is,the powder or paste material is first injected into the mold,through the heating of the mold and the rolling rotation in the vertical and horizontal direction,so that the material is evenly covered with the mold cavity and melting by its own gravity and centrifugal force,and the hollow product is obtained after cooling.In the whole molding process,the pressure in the mold will be atmospheric pressure.Allow air to flow in and out of the mold to achieve pressure balance.Avoid internal material leaving the mold. Avoid water from the outside of the mold.Maintaining the same pressure inside and outside the die helps:AVOID blowing holes in the die closing lines.Eliminate the flaring caused by pressure on the die closing line.The cooling phase reduces the possibility of warping due to pressure reduction.Avoid mold damage.Polyethylene rolling molding is mostly made of organosilicone oil or organosilicone resin with excellent heat resistance.

Using silicone internal release agent,it can be uniformly coated on the whole surface of the cavity;If the use of silicone resin release agent,then evenly coated with good release agent to slowly warm up,so that the solvent will be released,forming a thin layer of resin layer,and then at 250~280℃ temperature heating curing 1~2h,to have a certain strength of the release layer,then can be fed,roll molding.Silicone oil release agent coated to the mold cavity can only be used once,after each molding must be coated once,and the use of silicone resin release agent has a prominent advantage,that is,coated good release layer has"semi-permanent",can be used repeatedly.Because the mould used for rolling molding is not affected by external force,the mould is simple,cheap and convenient to manufacture.

In addition,the roller molding equipment also has greater mobility,a roller molding machine,not only can install a large mold,also can arrange several small chess tools;It can not only mold parts of different sizes,but also shape products of different sizes and shapes at the same time.As long as the raw materials used in the rolling products are the same and the thickness of the products is the same,the rolling molding process can be molded at the same time.Therefore,the rolling molding process has greater mobility than other forming methods.