XPS means eXtruded PolyStyrene. The very first thing you obtained to know may be the output. How much capability are you looking for? For instance, 500kg/hr or 1.5 ton each hour, there is huge difference when capacity varies. Furthermore, some connections are usually had by the output together with your product category. Say, if nearly all your product is in 20mm thick, or less, I'll Not advocate you the relative line a lot more than 300kg/hr. Vice versa, if you're going to generate XPS boards thicker than 100mm, I'll recommend you the relative range more than 1000kg/hr, for the higher thickness requires bigger stress gradient.
Well, permit’s get to the device back. Normally, today’s XPS range has tandem extrusion system, major extruder plus secondary extruder in two levels. Either single screw plus individual screw extruder, or twin screw plus individual screw extruder. One phase twin screw extrusion program was outdated about 10 years ago.
Speaking generally, XPS production line is contains feeding system, extrusion system, die, and downstream. Of all first, the feeding system. Mainly, you can find three forms of feeding system, loss-in-weight, auger and gravimetric feeding. They have big difference in cost also. Fig 1 is 7 elements loss-in-weight feeding system with vacuum cleaner loading system. In loss-in-pounds feeding system, eaceach materials will continuously be dosed and conveyed.ery unit offers its own load cell. Either powder or even pellets could work with loss-in-weight feeding system perfectly. The feeding selection of each material could possibly be big quite. Fig 2 is 7 elements gravimetric feeding program. In gravimetric feeding system, each material will be dosed in batch, combine it before feeding then. It has only 1 load cell for all. Both gravimetric and loss-in-weight could work with twin screw extruder, however, single screw extruder could work with gravimetric only, as the mixing and distribution performance of individual screw extruder is insufficient evaluating with twin screw extruder. The gravimetric feeding system gets the propensity of layering whenever your raw components have powder such as for example talc or pigment; like layering will affect the blending and distribution of materials somewhat, so if you make use of gravimetric feeding system, you much better use all components in pellets. Gravimetric feeding system is usually cheaper than loss-in-weight relatively.
Fig 3 can be an auger feeding program. Auger feeding is a lot cheaper compared to the other two, however the accuracy, mixing and work place is poor aswell comparatively. Comparing with additional two feeding program, auger feeding requires a minumum of one more work at feeding section, because workers need to weigh each materials and put them right into a pre-mixer manually. Then the pre-mixed materials will undoubtedly be transported to major extruder by an auger loader.
Concerning the primary extruder, personally, I would recommend you twin screw extruder as primary one strongly. A number is carried because of it of advantages. It is best at mixing, versatile screw profile, lower maintenance price and less additive consumption (it is possible to conserve 20% of flame retardant). You may already know, the blowing broker for XPS has progressed from CFC to HCFC, hFC then, now it’s CO2. There could be something new later on soon. And every era of blowing agent requires brand-new screw profile. How will you match the ongoing growth? Twin screw may be the answer. Unlike individual screw, our parallel twin screw is usually modular design. It is possible to change the screw profile based on the different process requirements, for other application even.
Now permit’s look at secondary extruder. The main reason for secondary extruder is cooling, therefore the cooling capability and the accuracy of temp control are very essential, that will be the primary factors to affect the actual physical property of the panel. We are using tailor-made oil temperature controller to regulate the temp of secondary extruder. All temp control is electronic setting, so foolproof it’s. The cooling channel style not only has something regarding cooling efficiency, but the protection of the barrel also. One more secret I must let you know that the screw within cooling is very important aswell. Fig 5 exhibits a rotary joint for screw inside cooling.
Now, we arrived at static mixer and die. Static mixer is made to reconcile the radial temp difference from the barrel walls to the main of the screw trip. The design can affect the top quality of final item. The look of die has big impact on the surface high quality and density of the panel that will determine your production cost. How big is the die could possibly be tailor-made for this size of final product.
The standard downstream includes calibrator, haul-off, edge hogger, main cut-off, edge trimming, packaging and stacker. But there are several peripheral devices like printer, surface area groover, and embossing device etc. The most famous size of XPS board is usually 1200X600mm (LXW), however, many application needs 1200mm broad or some particular dimension. This should be taken into your consideration.