What Are The Common Issues You’ll Find In HDPE Molding Machines?

HDPE PVC molding machine is the most economical option for industries. However, there are some common problems encompassing it. Let’s find out more about them. 

A PVC molding machine mainly helps in the packaging of hollow products like a beverage or chemical bottles. Although you can produce a perfect container with it, there are some problems with using this machine. However, knowing all of them beforehand will let us know their solutions immediately. So, deep dive into this blog to discover more. 

Top Common Problems In An HDPE Molding Machine 

  • Leakage 

There can be various reasons why an HDPE bottle leaks. It can either be due to the tear in the bottle’s wall or inefficient welding of the molten plastic. Another cause of it is the contamination of the melted resin by impurities or dirt. Most of these come out from recycled materials and result in the product’s wall leakage. For plastic products that have a narrow neck, the source of the leakage will usually be its top surface. 

  • Rocker’s bottoms 

Unstable or rocker bottoms in an HDPE molding bottle common happen due to improper cooling before removing from mold. In such cases, try increasing the water flow of your cooling system. Additionally, you may inspect the blow molding machine’s cooling channel to ensure that there is no blockage. Sometimes, the problem may be because of the excessive thickness of the flasher area’s parison lying at the bottom. Hence, ensure that the parison thickness is enough. 

  • Deflashing or tearing of the welding line

Thirdly, the deflashing of a container happens when the mold closes at a very slow speed. Thus to catch the person inside, you need to close the clamping unit in two steps. The first is by fast-speed mold closing and the second is by slow-speed mold closing. Both of them have different areas of application. For instance, if your bottle has a tearing, then slow-speed mold close is the ultimate solution. 

  • Defects in the surface wall

From tiny, unnoticeable defects such as black spots to large ones like horizontal ring lines, these bottles may have defects. Other problems in the surface wall include wall bubbles, vertical streaking lines, “orange peels”, etc. 

  • Uneven radical wall thickness

Finally, the biggest concern inside an HDPE molding machine is the uneven radial wall thickness distribution. Such products will always have a thinner side that has a much faster cooling than the thicker ones. Hence, it needs a longer cooling time otherwise the bottle can shrink. 


If you want to prevent these mistakes to happen, then you should always buy an HDPE molding machine from a reliable manufacturer. One such trustworthy name in the industry is Priti International. Operating for more than a decade, they know your ultimate industrial needs. So, contact them today.