1. Innovations in Filtration through exploitation of metal Additive Manufacturing
Louise Geekie
Project Manager
Project Director

2. About Croft
Croft Filters was founded by two brothers – Neil and Mark Burns – in Warrington in 1986
Initial focus was retailing mesh and finding practical uses for it
Natural progression led to the introduction of filter production
Today, Croft Filters is a leading manufacturer of customer specified filters
Croft founded by brother Mark and myself, found practical use mesh for mesh- customised filter manufacturers
We taken Croft from employing 2 people (next slide)

3. Croft as an SME: Vital Statistics
Employees: 23
Turnover: £1.4 million
Customer type: 40% new, 60% repeat
Nature of business:
No standard products
No production line products
Everything hand crafted
To 23 employees in the 28 years with a turnover of 1.4 million.
40% of our sales come from new customers and we have 60% sales from our returning customers.
However these return customers do not always order the same as before, it can be something totally different.
In fact for the most part we can say that we have no standard products, No production line products
Everything is hand crafted-from woven wire mesh (next slide)

4. Vacuum filter housing & filter
Industrial Filter Types
Bespoke filters can be made in any shape or size. Popular styles include cones, cylinders, baskets and screens.
Woven wire mesh sleeve
Anchor bonding
Mesh screen
Removes particulates from waste water
Wedge Wire screen
Cylinder Filter
Vacuum filter housing & filter
Removes powder particles from air
Filters can be manufactured in wire mesh and metal perforated plate

5. SUCCESSFULLY COMBINED FOUR OF SIX PROCESS STEPS ON ONE MACHINE
In-House Automation
SUCCESSFULLY COMBINED FOUR OF SIX PROCESS STEPS ON ONE MACHINE
PRODUCTION COSTS LOWERED SIGNIFICANTLY
That had been created as part of a smart grant for another innovation in tooling. The machine was underutilised. We still had to slit the mesh, before it was fed onto the former, then resistance welded, cut to length and crimped. Operator planged tube during wait for next. Successfully incorporated 4 steps of manufacturing process out of 6 into one machine. Significantly reducing production costs and time.
One other major area that we work on is innovation
Slit Mesh drawn into machine
2. Tube formed
3. Welded
4. Cut to length
5. Crimped
1. Slit Mesh
6. Flange
TSB Smart Grant

6. Conventional Manufacturing Process Filtration portion: woven wire mesh
Layers: filter and filter support
Possibility for one or two mesh layers to suit filtration requirements
Subtractive manufacturing method
Perforated Plate:
Bespoke Automation
Filtration portion: woven wire mesh
Inside to out (above)
Outside to in (below)
For filters consist of two layers, the filter (mesh) and the support. Material is removed from steel plate, here by punching machine and so is called subtractive manufacturing, with an amount of material waste.
When fluid passes through a filter in a conduit it has to turn through right angles to exit the filter, this creates turbulence and so increases resistance, also called the pressure drop. To decrease this resistance what we want is (next slide)
Welds

7. Filtration
Pressure drop across a filter determines the amount of energy required for pumping
Turbulence created by change in fluid flow direction increases resistance
Perforated plate
Filter support
Mesh filter
Fluid flow
13% UK industrial electrical energy is used for pumping
Costing £728 million in 2007
Represents 6% of the UK’s carbon footprint
For filters consist of two layers, the filter (mesh) and the support. Material is removed from steel plate, here by punching machine and so is called subtractive manufacturing, with an amount of material waste.
When fluid passes through a filter in a conduit it has to turn through right angles to exit the filter, this creates turbulence and so increases resistance, also called the pressure drop. To decrease this resistance what we want is (next slide)
The British Pump Manufacturers Association commissioned Report into pump usage in the UK (UK Pump Market Study”, by Steve Schofield (BPMA) and John Veness.2007

8. Effective Filtration: Product Development
FILTER PROPERTIES
Maximum open area
Maximum strength
Creates resistance
maximised open area and strength, can’t have both. Filter design also limited by aperture size required, operating pressures and conditions (acid neutral etc) and the space available. Mark had the idea, If you put the holes in line with fluid flow the resistance would be decreased, filter more efficient.
We tried to make this filter in many ways, drilling milling,
But could not make it conventionally, but then I went on a trip to Manchester Fab Lab (next slide)
LIMITED BY
Required aperture size
Operational pressure
Space available

9. Prototype Development and AM
FIRST PROTOTYPE:
Acrylonitrile Butadiene Styrene (ABS)
Fused Deposition Modelling AM technology
Where I attended and floated a ball down the canal and I saw 3D printing for the first time. A product is made layer by layer. They had an ABS machine and using TSB FS grant we had them make our prototype, in plastic. We then tested the AM filter in our flow test rig (next slide)
3 inch / 76.2 mm
‘Straightliner’ filter
Technology Strategy Board
Feasibility Study

10. Prototype Evaluation Flow Test Rig Decreased resistance
Short Knowledge Transfer Partnership: Product specifications
Flow Test Rig
Measures (±3%) the pressure drop of filters for water across a wide range of flow rates ( l/min)
The results were clear cut. The additive filter had decreased resistance and needed less energy for pumping compared to the conventional filter. Cost savings end user, decreased carbon foot print.
The ability of 3D printing to deliver high value filters presented a new opportunity so we looked into this new disruptive technology further (next slide)
Decreased resistance
Decreased pumping energy required
Cost savings to end user
Decreases carbon footprint

11. Single product, multiple components Innovation & diversification
Advantages of AM
Product materials
No tooling
Design freedom
Time to production
Less labour
the main advantages are metal additive manufacturing are design freedom:-you can make a product you cannot make conventionally which can lead to innovations and increased product diversity, no tooling required, prototype production, less lead and labour time the ability to make a product. So we took the plunge and ( So this technology could provide us with an automation process that requires no tooling, so we looked into the risks (next slide)
Single product, multiple components
Prototype production
Innovation & diversification

12. Becoming an Industrial Adopter of AM
We invested in an AM machine…
… and created new business: Croft Additive Manufacturing Ltd
And bought a machine and created a separate company CAM Ltd.
The machine we bought was (next slide)

13. Realizer 250 250 mm x 250 mm x 300 mm Stainless Steel 316L Video here
A Realizer 250. We particularly chose this machine as it had a large build chamber, could use different materials eg ss316L or Al amongst other metals. The product is build layer by layer with the laser fusing the metal powder to form the product according to the CAD design. So we take a 2D drawing, make a 3D drawing, add supports and upload to the machine. Production time is determined by height and volume of the product, lead time to final product less compared to conventional manufacturing.
The other advantages this machine have are (next slide)
Video here

14. Additive Manufacturing
INNOVATION AREAS
Filter design
Filter production processes
New products
VARIABLES
Laser
Intensity & duration
Powder
Layer thickness & type
Support structures
Angle of build
Design
That we can vary the intensity and duration and angle of the laser and also powder layer thickness: this changes the amount of powder fused. Change amount size of support structures. Taken together these factors contribute to the quality of the build. New features can be introduced into the design, eg decrease weight but also can build product that cannot be made conventionally. We have used our AM technology to advance our innovation in 3 areas: Filter design, production processes and new products.
Firstly (next slide)

15. Metal AM: holes–in-line filter
Designed around the holes in the filter
Built layer by layer
AM technology delivered energy saving filter
New Product
Design delivers decreased pressure drop, decreased resistance and decreased carbon footprint as per prototype
Holes in line filter in SS 316L, the design is scalable and delivered decreased pressure drop, decreased resistance and decreased carbon footprint as per prototype compared to the conventional filter. This new product cannot be manufactured conventionally and gives end users energy and costs savings.
When conventional mesh is molded into a shape (next slide)
Integrated filter support and mesh
SS316L
Scaled to height/filter diameter

16. Aperture Size and Shape
Woven wire mesh distorts aperture size and shape when moulded
Improved Product
Equivalent AM filters can maintain aperture size and shape
The apertures become distorted, changing size and shape. We used AM to build similar filters but here aperture size and shape is maintained over the surface area, improved an existing product.
We can also combine multi part components into a single part components. For some filters this is the integration (next side)

17. Integrated filter support and mesh
Integration: Support & Mesh
One component
Mesh & Support
Integrated filter support and mesh
Of the support portion of the filter and filter mesh portion. We can have different aperture sizes in different layers or a single size. Filter has the required strength and filtration capacity.
AM can also be used in manufacturing process to remove tooling needs as well as producing a multi part as a single part (next slide)
Single aperture size
Single Part Product
Different aperture sizes

18. Wedge wire Tooling required Winding of wires End caps
Wedge wire filters. Here are the conventional filters – describe.
We then build the WW filter in the AM machine(next slide)
Tooling required Winding of wires End caps

19. AM Wedge wire Multi to Single Part
Here we have built the 3 or 4 pieces if you include the wire as a single part. We can vary the ends slot size. Developing an application for Online customers to design their own.
AM has delivered (next slide)
Multi to Single Part

20. Improved Manufacturing Process
AM Wedge wire
No tooling
Lead time greatly reduced
Can be easily made in other sizes, with no tooling requirements
Customer customisation
Multiple parts produced as single component
Here we have built the 3 or 4 pieces if you include the wire as a single part. We can vary the ends slot size. Developing an application for Online customers to design their own.
SO Croft has adopted AM and (next slide)
Improved Manufacturing Process

21. A copy…
CONVENTIONAL FILTER DISC Recesses in rim and mesh Difficult to clean to very high standard
Where we made a retaining rim, with a mesh in the centre, same as on the left BUT stronger, and with no recesses where contaminants can accumulate, within the rim, between the woven wires.. This disc can be cleaned to a very high standard which attracted the attention of a company who needed to be able to clean their filters to a pharmaceutical grade. They gained the benefit and after seeing the results are now looking at how AM may help them with other process problems, When you can see the range of products (next slide)
AM FILTER DISC
No recesses
Easier to clean
….no, not quite!

22. Improved Industrial Process
Combining conventional with AM
CONVENTIONAL FILTER
Quick release filter
Woven wire
mesh
Perforated
plate support
AM Filter Disc combined with woven wire mesh
Improved Industrial Process
Easy to remove
easy to replace mesh
easy to clean
Adhesives, Resins
Hygenic processes
Water
Fuel dispensing

23. AM Filter Designs Solution Design Designed around holes New Product
Designed for AM
Variable Lattices
New Product
We have used AM to develop New products, filters that cannot be made conventionally, deliver energy and cost savings to customers.
We have developed AM filter designs that have increased strength, uniform aperture sizes, and saved time and labour in delivering adaptable wedge wire filters
We as a company can see the benefits of AM but for others in industry (next slide)
Long Lead time
Multi-part to single part
New Manufacturing Process
Decrease pumping energy
Decreased carbon foot print
Improved Filtration

24. Industry’s adoption of AM
Perceived Barriers
Have a product that works
Don’t need new products Will it work? Will it cause down time?
Expensive
Don’t know what it is: metal 3D printing
Lack of understanding of how it works
There are barriers to the adoption of AM in industry, why replace a known art that works and may cause a whole process to be shut down. Unless there is a perceived need by the customer they will not want it. Using metal 3D printing-rather not but people get the idea of it, a better understanding of how it works will introduce opportunities to individuals to improve their own processes. An example of this is when we made in essence a copy of a filter disc, (next slide)

25. AM non-filter applications
Prototype Development
Shoe Industry
New Product & New patent
Prototype Development
Scientific Research
New Component
Rapid delivery
Automotive Industry
Complex series parts
Process Development
Pharmaceutical & Printing
Decreased downtime, novel
delivery

26. AM opportunities

27. Thinking differently opens doors
Thank You
Louise Geekie