When faced with a challenge from a processor requiring a shot weight of 110 kg, Chen Hsong turned to one of its large two-platen machines with a special modification. The solution was to configure a 6,500-tonne SM6500-TP injection molding machine with two parallel injection cylinders of 55 kg shot weight capacity each in a “Y” configuration.
Chen Hsong recently delivered the unit to Australian processor Trident Wastewater Services (Adelaide, SA) for molding large septic tanks from polypropylene in a single color. Shot volume is an incredible 152,094 cubic cm.
Further, two injection cylinders deliver a high degree of processing flexibility to the molder lest it want to use the machine for another application in that minimum shot size per cylinder is just 15 kg. The option of using just one injection cylinder is possible.
“Customers who come to us nowadays are not asking for a machine with a specific clamping force. They are coming to us looking for a solution, be it in medical, automotive or other sectors,” Ringo Au, head of international sales for Chen Hsong. The company offers a variety of clamping unit and injection unit options for the SM-TP Series to cater to varying industry requirements: 14 clamping tonnages in all are available between 700 and 6500 tonnes and also 29 shot weights ranging between 1968 and 106,081 grams per cylinder (meaning the options are even more abundant when considering the Y-configuration permeations). The permeations for combining clamping and injection options are thus numerous.
|“Y” configuration large injection molding machine delivers shot size flexibility for processors|
Chen Hsong two-platen machines are selling extremely well in the market of late. The company reports 126 on order for delivery through to March 2017, including 700-tonne, 2200-tonne, and 3600-tonne units.
Key performance attributes include a dry cycle time (according to the Euromap 6 standard) of 6.8 seconds for the 1900-tonne SM1900 injection machine, high concentricity of screw and barrel of 0.07 mm, and +0.1% injection precision by utilizing a specially-designed injection screw, and optimized hydraulic and control systems. Further, electric plastication employing a servo motor and gearbox is offered as an option, which boasts 90% energy efficiency versus 77% for the efficiency of a hydraulic injection unit.
Chen Hsong has also worked to reduce sound levels during machine operation. The latest machines operate at a sound level of is 80 dB versus 84 dB for the national standard in China.
Leading Chinese auto OEMs are among users of Chen Hsong machines that the machine builder is working with, including an auto parts molder in Chongqing that is using a 1650-tonne SM1650 machine with the D130 injection unit (screw diameter of 130 mm, which is the standard injection unit for this machine size) to mold an instrument panel, and an auto parts molder in Shanghai which is employing the same type of machine to mold a mat.
Another auto parts supplier is using two Chen Hsong two-platen machines, a SM1650 model and a SM1050 model, to mold seat backs for the Audi Q5 using a low-pressure injection technique. The machines use Chen