Injection Moulding & Filtration

  • Polishing Hydraulic Oil
  • Injection Moulding Systems
  • Injection Moulding
  • Clean Oil
  • Case Study


Injection moulding is the process of injecting molten plastic at high pressure into a mould to form a given shape. Hydraulic pressure is at the heart of most injection moulding machines, regardless of the make. The hydraulic system provides the force behind pushing the product into the mould and then splitting the mould open again.  

Water is also used on many injection moulding machines to provide cooling to the tools. The environment that the hydraulic system works under is often subject to both fine particulate and water ingress.

Injection moulding machines require exceptionally clean hydraulic oil as most are servo controlled. Servo’s are manufactured with extremely fine tollerances and any dirt or water ingress can cause them to stick or jam.


Injection Moulding Company manufacturing toys in Nottingham


A toy manufacturer local to Filtertechnik in Nottingham was experiencing damage to hydraulic components on its injection moulding machines due to contaminated oil. This led to costly replacement of pistons (£700-£800 per piston), valves and ultimately the hydraulic oil. Each injection moulding station requires circa 200 litres of clean and dry oil every 3-4 months costing around £600 per oil change.  

The Solution:

Filtertechnik were contacted to see if they could simultaneously reduce machine break downs and also extend the life of the hydraulic oil.

What their Engineers designed was a low cost kidney loop filter system utilising 4 of their Hippo filters. This filter removes both water and solid particulate down to under 3 micron. The replacement elements hold extraordinary amounts of dirt and water and have the added benefit of being a low cost consumable. The machine supplied has a flow rate of 10 Litres per minute. The machine is portable so can be moved from machine to machine as required. The resultant oil is cleaned and dried down to ISO 14/9 (NAS5 or below) and is well under 100ppm water content. Visually the oil is changed from a dull slightly cloudy oil to one that is clear and bright.


                            Injection moulding Company Employer: 

     “The Hippo filtration system has worked faultlessly saving us time and money”




The Hippo filter system cost under £2,500 to install and has saved the company many multiples of this investment in saved down time, no equipment spares costs and no catastrophic failures since its deployment. Hydraulic oil changes have been extended to yearly rather than quarterly and could actually be extended further quite safely such is the faith in the Hippo filter!
On-going element usage is not expensive as each Hippo element has a list price of under £35ea.

For more information email: or alternatively call: 0115 9003600