Accelerating Cleaning, Safeguarding Results & Reducing Risk in Pilot Plants

A UK Pet food Manufacturer contacted us requiring 4 easy clean high viscosity transfer pumps for the transfer of tallow in a pilot plant being used in a new blend of pet food. Tallow – an animal fat from Beef or Mutton which has had its moisture removed extending its shelf life, has a dry waxy texture, is solid at room temperature and is rich in vitamins and flavour.

Pilot plants are a smaller scale version of a newly designed production facility which are built for the testing of methods, procedures, ensuring the intended design produces the outcome or recipe they require and for proof of concept for investors before a much larger design is produced requiring heavy investment.

As the customer was trialing several recipes of pet food, they wanted to guarantee batch results, accelerate the speed of cleaning between differing blends as well ensure bacterial contamination was not incurred.

Pet Food Safety Standards

Pet food is subject food safety standards with requirements for producers to identify Risks, perform Hazard Analysis and ensure Critical Control Points known has HACCP are adhered to. Producers are required to undertake bacteriological sampling frequently as well as have a safety management system.

Typically in such plants, industrial stainless steel pumps are used which are constructed in standard stainless steel which are not easily cleanable.

The customer wanted a variable flow pump where flow could be reduced by up to two thirds, yet pressures remain consistent at up to 6 Bar. They also wanted a pump which was easily cleanable when mounted on a skid frame forming part of the plant design.

North Ridge specified and supplied 4 Hygienic Progressing Cavity Pumps for this pilot plant with well-polished internal parts to ensure parts could be cleaned and sanitized effectively in minimal time frames.

As the customer wanted to automate cleaning, ensure plant uptime was maximised and fully disinfect pumps between batches, the pump was manufactured from AISI316L then Polished to Ra1.6-3.2um (a micron polishing level).

Various polishing levels are available to buff pump internal parts with some of the most common standards listed below:

Table of Pump Polishing Standards and Levels

Nominal Grit Size Standard BS 1449 Pt. 2 Standard EN 1088-2 Description / Appearance
80 – 100 3A 1G/2G Ground Ra nom 2.5 μm
180 3B 2J Ground Ra nom 1.25 μm
240 4 1J/2J Dull Polish nom 0.6 μm
320 5 1K/2K Satin Polish Ra >0.5 μm
590 – 630 7 2P Bright Polish Ra nom 0.05 μm
800 8 1P/2P Mirror Finish Ra nom 0.05 μm


Hygienic Pump Design

Polishing a pumps internal stainless steel parts enables internal parts to be easily sanitized, and ensure that pumped media is easily removed from the body or moving parts. It also ensures the pumps internal hygiene can be maintained via Cleaning in Place (CIP) or Sterilisation in Place (SIP) without dismantling of the pump for manual intervention.

Furthermore a hygienic Open pin joint ensures superior sanitation, with lubrication of this joint is provided by the pumped product, preventing the introduction of cross contamination from lubricants. It can be quickly maintained, assembled and dismantled without the need for tools.

This is important as pet food is subject to similar controls to that of feed for livestock in particular with additives, animal origin and bacteria levels to reduce the risk to public and animal health.

The unit was coupled to a geared motor as progressive cavity pumps require high starting torque, . this design of motor multiplies the output torque without increasing the power consumption of the motor.

The pumps were assembled on AISI304L baseplates, supplied and delivered within 6 weeks from order.

If you are looking to accelerate cleaning in place, automate pump cleaning or reduce risk visit or call 01773 302 660 to see how we can help. With over 100 application case studies, we know how to get it right.