PPSL (Precision Processing Services Ltd)

  • Carrakeel Industrial Estate
  • 60 Clooney Road
  • Londonderry
  • Co Londonderry
  • United Kingdom
  • BT47 6TR (map)

  • Tel: 028 7186 0001
  • Fax: 028 7186 1211
  • Website: www.ppsl-precision.com

Precision Processing Services Ltd

Precision Processing Services Ltd

Founded in 1999, Precision Processing Services Ltd (PPSL) was set up as a joint venture with Southern Metal Processing based in Alabama USA, www.southern-metal.com, to service a range of equipment for a multinational polymer manufacturer based in Londonderry. PPSL now provide services to industry throughout UK and Ireland, Europe and Asia.

We specialise in the chemical refurbishment of contaminated industrial process equipment. Our technical team design the process taking into account the contamination, the materials of construction of the equipment and the customer's requirements to provide the optimum clean. In conjunction with chemical refurbishment we offer process engineering solutions with an aim to improve our customer's process through advice and modification for optimum performance.

We have experience in refurbishing parts for the Polymer, Oil and Gas, Chemical, Utility and Food and Beverage sectors, amongst others. New sectors provide new challenges and this has required research and development into alternative cleaning processes. Our processes have expanded across the years to account for a wide range of industrial process equipment.

We can offer the latest in cleaning technology, filter performance tracking and a comprehensive inspection and testing regime.

PPSL is part of the Precision Group, is an ISO Quality accredited company and is FPAL registered.

Industrial Services

Industrial Services

PPSL offers a range of cleaning and testing services for all kinds of industry. We currently provide specialist services in the following sectors:

  • Chemicals Processing and Manufacturing
  • Oil and Gas Production and Processing
  • Petrochemical Processing and Manufacturing
  • Rubber and Plastics Manufacturing
  • Polymer Processing
  • Utility and Power Generation
  • Automotive, Marine, Aerospace and Defence Industry
  • Pharmaceutical Manufacturing
  • Food and Beverage Processing
  • Medical Device Manufacturing
  • Printing and Packaging Industry
  • Agricultural Industry
  • General Engineering Industry
  • Electronics and Microelectronics Industry
  • Filter Manufacturing


PPSL utilises a comprehensive range of controlled cleaning processes to ensure the highest possible cleaning standards for every part passing through its processing plant. Parts processed from the industries listed above include:

  • Metal Filters
  • Ceramic Filters
  • Pumps
  • Valves
  • Gears and Bearings
  • Heat Exchange Equipment
  • Extrusion Equipment
  • Mixing Equipment
  • Pipework and associated pipe fittings

We undertake research into new cleaning technology and new cleaning chemistry to allow us to provide the best refurbishment service for our customer's parts. 

Filter Cleaning

Filter Cleaning

We offer a comprehensive and tailor-made filter cleaning service. Our filter cleaning service is designed around the process fluid, the contamination and the materials of construction of the filter to remove unwanted materials leaving the filter ready for re-insertion into process.

Some examples of filter contaminants we have removed include:

Polymers (e.g.: polyester, polycarbonate, cellulose)
Speciality Polymers (e.g.: PEEK, PI, PAN precursor for carbon fibre)
Oil (e.g.: transformer oils, hydraulic oils, petroleum oils)
Solvents (e.g.: toluene, ethanol, propanol)
Catalysts (e.g.: vanadium based, nickel based, FCC)
Filters and Additives (e.g.: titanium dioxide, monomers and pre-polymers, barium based)
Process Contaminants (e.g.: water scale, rust)

We also undertake dismantle and reassembly of filter bundles, and complete filter units. This provides customers a range of different options to choose from which are suitable to their specific process requirements. Our filter cleaning service is enhanced by our filter integrity testing service allowing parts to be tested against manufacturing data to qualify them suitable for re-use.

Filter Integrity Testing

Filter Integrity Testing

Filter integrity testing is important to ensure filters are suitable for use, especially if the filters have been cleaned. All data gathered during filter integrity testing is logged onto our database allowing us to track performance across successive cleaning cycles.

PPSL offers a range of different tests to determine filter integrity. The simplest of these is Initial Bubble Point. This test indicates the largest hole in the media, and is a good determinator of suitability for re-use. The measured Bubble Point can be compared to manufacturers data and so filters can then be easily qualified as Pass or Fail.

The next test used is the Wetted Air Flow test, and this is an extension of the Bubble Point test. This test gives an indication of the mean pore size of the filter. This Flow test can be enhanced by our skilled operators with a visual check during the Flow test to assess the overall flow performance of the filter and highlighting any untoward flow characteristics.

Weight check is also performed on filters. The weight of the cleaned filter is compared to the base weight of a new filter allowing us to assess that all contamination has been removed from the filter.

Differential Pressure Testing can also be performed. This test can be undertaken using the medium of air or water, and is undertaken to describe the differential pressure across the filter at different flow rates. The measured performance can be graphed and compared to manufacturers data to determine suiability of filter use.

Benchmark testing, i.e. the testing of filters before use, is very important to provide sufficient data to compare cleaned filters to. Benchmark testing also provides customers with data on their filters before initial use. We always recommend customers send their new filters to PPSL for benchmark testing before use.

Support resources

Call Applegate +44 (0)345 600 7177 AS