"Engineered Surfaces for Exceptional Performance"
"Engineered Surfaces for Exceptional Performance"

Article Index

The Metal Spray process can provide engineering coatings including anti-spark, chrome replacement, non-stick, reclamation, thermal barrier, wear resistant and grip coatings.

Some areas of application where MSSA equipment and consumables are used in the Engineering Production industry include the following:


Aerospace - Metal and Ceramic Coating Solutions

Thermal sprayed coatings have been a recognised and trusted solution for engineering coatings in the aerospace industry for many years. Many applications exist in the Aerospace Industry requiring metal and ceramic coatings for hard chrome replacement, anti-fretting and wear, clearance control etc. As well as the wide range of consumables the applications also call for a wide range of equipment to be employed for the application of the coatings including HVOF, Plasma, Arc Spray and Flame Spray.

Typical Applications Include:

  • Compressor casings - abradable clearance control coatings.
  • Blade tips - abrasive ceramic coatings.
  • Combustors and discharge nozzles - zirconia based thermal barrier coatings (TBCs).
  • Turbine vanes and blades - high-temperature oxidation resistance (overlay coatings and bond coats) and thermal barrier coatings.
  • Seal segments - rub-tolerant coatings.
  • Seal rings - chromium carbide and cobalt based high-temperature wear resistance coatings.

Oil Drilling Equipment Coatings

A hard-face super-stainless HVAF coating has been developed to withstand corrosion from salt and hydrogen sulfide, as well as abrasion met on housings of down-hole pumps and motors of oil drilling equipment. The coating exhibits bond strength over 12 KSI and hardness 52-55 HRC. Applied to 6 or 12 mils thickness, it is flexible enough to withstand deformation of elongated parts during handling and service.

The coating performance is proven in industry, where over 25 miles of housings have been already coated during these (past few) last years. Current coating production exceeds 2 miles of housings per month.

Application Case:

Spray Work

Electric Submersible Pumps
Motor housing

Unit Electric Submersible Pumps
Industry Oil Drilling
Problem Solved Corrosion/Abrasion
Coating Type Hard super-stainless 
Result of Application Pump lifetime increased  4-fold; in the most severe conditions – up to 10-fold; higher strength, corrosion and wear resistance than Monel coatings, 7-fold more economical alternative to stainless steel piping
Reference

Technological Systems for Protective Coatings Ltd. /Plackart Ltd.,  Moscow Region, Russian Federation


Slurry Pump - Case Study

HVAF equipment is utilised to protect slurry pumps' wet parts from erosion and abrasion as a result of hard solid particles. The HVAF coatings extend component life which in turn enables longer mean time between failures and significantly reduces maintenance costs.

A slurry is a mineral feedstock to be processed in a mining concentrator plant or a waste stream of tailings including hard particles. In oil and gas refining, slurries are usually catalyst streams, including limestone or zeolites. Under unfavourable circumstances of corrosive media, the combined effect of corrosion and erosion can lead to dramatically increased wear rates.

The mechanical and chemical forces are extremely demanding for the material integrity of pump parts — especially when temperature, pressure or flow volume increases.

Background: A customer asked us to coat a slurry pump backing plate to protect it from the abrasive slurry passing through the pump. The slurry consists of gypsum, aluminum oxide and water. The impeller came from the manufacturer already coated with tungsten carbide, presumably by a HVOF process. The pump housing was uncoated and the customer didn’t want the housing coated as, in previous experiences with this pump in this particular application, the backing plate was the only part adversely affected by the pumped slurry. 

Results: Figure 1 shows the backing plate with the applied HVAF tungsten carbide coating after one year of service.

After measuring the coating thickness, we found that the thickness after one year of service was identical to the original applied coating thickness. As we began to examine the backing plate we found an interesting area (see Figure 2).

The backing plate seal to the housing wasn’t absolute and some erodent made it past the coated surface of the backing plate and eroded material from under the coating. It is hard to see in the photo but the coating is undercut and is still intact forming a sharp overhang of coating. Figure 3 shows a close up of the eroded area.

The other main parts of this slurry pump didn’t fare as well. The impeller shown in Figure 4, lost much of the applied coating and the blades were wearing away fast. If the pump didn’t begin leaking the impeller would have failed after little additional service. In the close-up view you can see where the HVOF coating has completely gone (Figure 5). In those areas where the coating is worn away, the metal is being worn away quickly due to the blades being significantly shorter than the adjacent blades that still have coating remaining on the surface. This can be seen using a straight edge and a little back lighting (Figure 6).

The pump case didn’t do well either. Here is a look at it as received (Figure 7).

The damage is readily apparent in Figures 8, 9 & 10, where closeup views shoe the extent of the damage.

The customer decided that the best course of action was to line everything with a WC-10Co-4Cr tungsten carbide coating, applied with a HVAF system. We wholeheartedly agreed with this decision.


Aluminium Casting - Saint-Gobain Coating Solutions

Spinel spraying with the Master Jet.

Industry: Aluminium Casting Plant

Equipment: Spoons, chutes, funnels, moulds.

Principle of the Process: Aluminium metal casting requires tools to transfer the molten metal to the moulds or dies. Those tools (spoons, chutes, funnels) are made of steel.

Problem: Tools in contact with molten aluminum are subject to surface degradation and oxidation. Metal slag sticks on the tool surface.

Service Conditions: 

  • High temperature ~660°C (1220°F), resulting from the contact with the molten aluminium.
  • Metal slag sticks at the surface of the moulds, chutes, funnels.
  • Severe thermal shocks resulting from the casting cycle.
  • Corrosion and oxidation can occur with several aluminium alloy (Al-Si) compositions.

Metal slag sticks at the surface of the chute.

Coating Solution: Spinel Flexicord Coating.

Benefits of the Spinel Flexicord

  • Spinel Flexicord coating provides reduced sticking (large wetting angle) versus liquid aluminum metal.
  • Cleaning of the spinel coated tools is much easier and requires less time (low sticking of the metal slag).
  • Spinel Flexicord coating is a thermal shocks resistant coating.
  • The tools lifetime with a Spinel coating is at least twice versus tools without coating (minimum 200% benefit in lifetime).
  • The spinel coating can be removed and it can be rebuilt indefinitely.
  • Spinel Flexicord is easy to apply by hand on complex shapes and large components with a Top Jet or Master Jet gun.
  • Spinel Flexicord coating is less stressed and less subject to spallation compared to plasma sprayed coatings.

Coating Features: 

  • Product Ref: 9821 070 47 000.
  • ~300 coating thickness on 100 to 150 µm of NiCrAlY bond coat.
  • Roughness Ra 16 µm - Porosity 17 %.
  • Expansion Coefficient (C.T.E) : 8.8.10-6 at 0 – 980 °C.
  • Micro Hardness: 1140 Hv300g.
  • Surface weight ~890 g/m²/0.3 mm.
  • Surface coverage 2 m²/h/0.1 m.

Plasma Ceramic Coatings

Metallisation customer Woof Thermal Management Technology has applied well proven plasma ceramic coatings technology to high performance automotive applications, to provide highly effective thermal barriers in extreme conditions. 

Woof Thermal Management Technology, based in Bradford, West Yorkshire, UK provides premium specialist  coatings and engineering services to industry and end users. The plasma ceramic coatings range has been developed for the nuclear industry, but is proving itself to be very effective and valuable in heavy engineering, aerospace and motor sport industries.  

Using Metallisation Plasma spraying equipment, Woof Thermal Management Technology has extensive experience in supplying premium thermal barrier coatings to the motor sport industry. Woof coatings have been specifically developed to reduce under bonnet temperatures, increase power output and increase the reliability and longevity of ancillary components. 

The durable plasma ceramic coating provides a highly effective thermal barrier on exhausts, turbo’s and brake parts and enables high performance vehicles to run at cooler temperatures. The plasma ceramic coatings work by preventing heat transfer, which means an increase in power and reduced heat input to other components. A typical drop of 25ºC in under bonnet temperature will result in decreased intake temperature, which can give up to a 5% increase in power and significantly increases ancillary reliability. 

The Woof plasma ceramic coatings can reduce surface temperatures by up to 160ºC and can withstand temperatures of up to 1400ºC.  This compares with typical standard ceramic containing paint, which may only reduce surface temperatures by up to 9%. 

The Woof premium performance plasma ceramic coating contains magnesia / zirconia and offers the best thermal barrier coating. The coating is creamy white in colour, with a slightly rough surface texture.

There is an alternative darker plasma ceramic coating, which contains alumina / titania and has a grey coloured appearance.   This offers similar reductions in surface temperature, although the radiation of heat is slightly greater than with magnesia / zirconia.  In all cases, except maybe some extreme situations, this coating gives the performance advantage but is less prone to aesthetic degradation due to its darker colour.  This means the coating stays fresh and smart looking, which may be important for concourse cars.

The well known white exhaust coatings became very popular in the 1990’s and are applied on many new breed turbo charged four wheel drive world rally cars.  The proof of their success is demonstrated by the teams who opted for these coatings, which include key players in the industry such as Subaru and Mitsubishi.

These days the use of ceramic coatings has become widespread including Touring Cars, Super Car manufacturers and various rallying disciplines, which have led through to private owners using the coatings on track day cars and fast road cars. Woof Thermal Management Technology currently supplies Mellors Elliot Motor sport and the works Proton S2000 Team. 

John Holdsworth, Managing Director at Woof Thermal Management Technology, says: “It’s a really exciting time for Woof and we are thrilled to be expanding our services within the motor sport industry. To support our commitment to the industry we have decided to sponsor the Lancashire & Districts Subaru owners’ club ‘Best in Show’ trophy at the prestigious Preston Flag Market car show in April.  This lets us get close to the car owners and provides great networking opportunities.”


Anti-Spark Coatings on Crane Hooks

Reason for use: To remove the potential for sparking between two steel components.

In the Oil, Gas and Petro-Chemical Industries or the storage of munitions, there is always a very high risk of fire or explosion due to spark hazard. The sparks often being caused by friction between two steel components.

By using the Metallisation Arc or Flame spray Process, it is possible to remove this major source of spark hazard by applying a thin layer of phosphor bronze onto the offending surface. One of the most common components to be treated in this way is crane hooks, but it is also possible to apply this type of coating to steel fan housings or forklift truck forks. Metal spraying is an economic method of producing a spark resistant surface on any standard manufactured steel component.

Equipment: In this case Arc Spray Equipment was used.

Materials: Phosphor Bronze Arc Wire - Easily machinable material, very good for bearing surfaces and giving an excellent anti-spark coating.

Method - Cleaning

  1. Steam clean if equipment available.
  2. Degrease by solvent vapour process, if material available.
  3. Check all surfaces are free from contamination and debris.

Preliminary Inspection

Check for cracks or surface imperfections taking hooks below the manufacturers recommended operating tolerances.

Preparation

  1. Mask surfaces adjacent to area requiring treatment with a heavy duty masking tape.
  2. Thoroughly inspect for contamination prior to blasting.
  3. Thoroughly blast the area to be sprayed with clean chilled iron grit grade G24.
  4. Ensure that areas to be treated are thoroughly blasted A surface profile of between 75μm-100μm should be achieved. It is important that the surface to be sprayed should not come into contact with hands, oil, grease or other contaminants which may cause bond failure after spraying. Delays between blasting and spraying should not exceed 20 minutes.

Application of Sprayed Coating

Bonding and Simultaneous Spraying of Phosphor Bronze.

  1. The Arc spray Equipment should be set up in accordance with the MSSA Manual for the spraying of Phosphor Bronze.
  2. The area to be sprayed should be cleaned with a vacuum cleaner or a clean, dry air blast to remove any loose particles of dust or grit.
  3. The first 75μ-100μm should be applied at close range (typically 100mm) and at lower air pressure to achieve a higher bond strength.
  4. The coating should be applied evenly by rotating the component in front of the Arc spray Pistol, keeping the spray-stream at as near as possible to 90° from the surface being treated.

Bond Coat

Spraying parameters for Bond Spraying Phosphor Bronze.

  1. Range: 100mm
  2. Nozzle Air Pressure: 3.7 bar (55 psi)
  3. Volts Before Spraying: 32-34V
  4. Volts During Spraying: 28-30V
  5. Current: 200A

Note: Parameters may differ in accordance with type and length of power cables and hoses being used.

Main Deposit

  1. Apply Phosphor Bronze final deposit to specified required thickness (typically 0.40-0.50mm).
  2. The coating should be applied evenly by rotating the component in front of the Arc spray pistol, keeping the spray-stream at as near as possible 90° from the surface being treated.

Spraying parameters for Main Deposit Phosphor Bronze.

  1. Range: 150mm
  2. Nozzle Air Pressure: 4.3-4.6 bar (62-87 psi)
  3. Volts Before Spraying: 32-34V
  4. Volts During Spraying: 30-32V
  5. Current: 250A

De-Masking

  1. Remove all masking tape.
  2. Remove all over-spray taking care to prevent coating damage.

Inspection

  1. Check dimensions.
  2. Check for cracks, defects in sprayed coating, i.e. large pores or protrusions and loose particles.

Finishing

Under normal circumstances, it is possible to use the component in the as-sprayed condition without any problems but for cosmetic purposes, a light polish may be required.


Shaft Coatings with HVAF

Kermetico HVAF & HVOF technology and equipment allows the deposition of impermeable, hard and ductile wear resistant shaft coatings.

The high ductility of our metal ceramic shaft coatings reduces the risk of cracking if flexed and provides loading stress resistance while an optimal surface structure provides improved friction between a shaft and a bearing.

HVAF Spraying of a Wear Resistant Coating onto a Shaft

Compared to traditional electrolytic hard chromium plating, our shaft coatings are characterized by significantly higher wear resistance and the absence of hydrogen embrittlement of high-strength steels. They also have a better quality/price ratio than most other surface engineering methods.

Shaft Wear in Seals and Bearings

Wear of a Shaft Under a Seal

Radial shaft seals must run against a smooth, round shaft surface to seal efficiently. If the shaft becomes worn, the seals will no longer be able to fulfill their function, which is to retain lubricant and exclude contaminants.

Typically, the shaft becomes scored when a contaminant particle is caught under the sealing lip and abrades a track as the shaft rotates. As this continues, the seal will enable more particles to pass or get stuck, and seal efficiency deteriorates, eventually leading to malfunction of the component that the seal is meant to protect.

Shaft Wear in its Bearings

Under normal running conditions of full fluid lubrication wear of a shaft in its bearings is due primarily to the presence of grit, etc., which is imported into the bearing by the lubricating oil. Particles of grit, too small to be caught by any filter, become embedded in the surface of a bearing material but may still project sufficiently to span across the oil film when it is at its thinnest and so to lap the shaft. To a secondary degree it is due to attrition, when owing to the thinness of the oil film, the high spots on both members of the bearing come into metallic contact, but with highly finished surfaces, and an ample supply of lubricant, it is doubtful whether wear by attrition is an important factor provided that the materials are compatible and are not such as will readily weld together. Clearly, the higher the mean loading, the thinner the oil film will be on the loaded side of the bearing, and therefore the greater the intensity of the lapping process.

The harder the surface of the shaft or the softer the bearing material the particles will more readily be driven home into the latter and so out of harm’s way. Other things being equal, the rate of wear of the shaft will depend on the difference in surface hardness between itself and the material of the particles.

That is why different techniques of surface treatment are being used to protect a shaft surface.

The Features of Our HVAF Coating Technology

We recommend the application of Fe-based materials to protect shaft surfaces. Depending on the shaft base material, environment, sealing and bearing conditions we recommend using SS350, SS410, SS431 or harder 6AB coatings. For the most demanding applications, we use tungsten carbide coatings.

Just 100 µm of our coating is gas-tight, impermeable to gas or liquid without additional sealing.

Kermetico High Velocity Air Fuel (HVAF) technology has been shown to be very competitive as an environmentally friendly alternative to electrolytic hard chromium (EHC).

The ecological aspect and shorter processing time reduce processing costs.

The option to apply thicker layers provides a way to repair heavily worn components.

Kermetico HVAF metal and carbide coatings are also superior to conventional HVOF counterparts regarding wear resistance, corrosion protection and production cost. The higher velocity of the Kermetico HVAF in-flight particles (over 1,000 m/s) enables the production of coatings with high bond strength and low porosity.

Moreover, the low combustion spraying temperature (1,960-2,010 °C / 3,560-3650 °F) and gentle particle heating lead to minimal feedstock phase transformation and almost nonexistent elemental depletion/decomposition of the in-flight particles.

Furthermore, the replacement of pure oxygen necessary for HVOF with air in our HVAF process significantly reduces the oxide content of the coatings, which is desirable for high-performance coatings.

The result – gas-tight metal or carbide coatings, impermeable to gas or liquid.

The Kermetico HVAF System Spraying a Repair Coating onto a Shaft

The Kermetico HVAF Shaft Coating Method

The traditional thermal spray coating approach is to melt and atomize the feedstock, propel it to the surface of the target part whereupon contact ‘splat cooling’ builds up a coating.

The Kermetico HVAF process operates on a different principle “heat slowly, spray faster.“

We heat the feedstock material to near its liquid phase temperature without exceeding it.

Then we accelerate the particles to an optimized high velocity, and when the particles impact the substrate, there is a rapid conversion of kinetic to thermal energy that allows for plastic deformation of the particle and a bond that we cannot accurately measure.

In the ASTM 633C bond test, the only result we get is broken glue, even with 0.040“ (1 mm) of the WC-based coating.

A Polished Shaft with a Kermetico HVAF Coating

Blasting and Spraying Shafts with Kermetico High Velocity Equipment

Usually, we deposit coatings using robotic blast and spray operations.

We blast a shaft surface with a Kermetico HVAF gun (it is extremely fast and uniform) and spray with the same gun after switching the powder feed hose and perhaps changing the nozzle.

It is much faster, more accurate and needs much less grit than manual blasting.

HVAF grit blasting also produces very even surface preparation and induces less stress into the base metal of a shaft.

The multi-purpose HVAF AK systems are recommended for this application - AK7 for large shafts, AK6 for medium shafts and AK5 for small shafts.


Flash Carbide Coating of Titanium Parts for Hard Chrome Replacement

Hard Chrome Replacement with HVAF Thermal Spray Equipment and Coatings

There is an increasing demand for a cheap alternative to electrolytic hard chrome coatings in corrosive environments. The market needs environmentally friendly long-lasting tungsten carbide coatings or inexpensive stainless steel coatings.

Kermetico HVAF technology and equipment provide a way for hard chrome replacement with impermeable, hard and ductile coatings that are inexpensive and easy to apply. Numerous researchers have pointed out that HVAF coatings work several times longer than electrolytic hard chrome does having the same or lower cost.

How do we thermal spray coatings as cheap as hard chrome plating?

  • We spray thin gas impermeable coatings with roughness low enough to avoid grinding.
  • We spray it fast.
  • We have the systems to spray it onto outer and internal surfaces.
  • We have developed the technology to do it without failures.

Features of Kermetico HVAF Coatings for Hard Chrome Replacement

The Kermetico High Velocity Air Fuel (HVAF) process has been shown to be very competitive as an environmentally friendly alternative to electrolytic hard chromium (EHC).

Kermetico HVAF carbide coatings are superior to HVOF and EHC rivals in corrosion protection, wear resistance and production cost. The high velocity of the in-flight particles (faster than 1,000 m/s | 3,280 ft./sec.) in our HVAF process enables the production of very dense coatings with high bond strength.

Moreover, the low combustion spraying temperature (1,960-2,010°C | 3,560-3,650°F depending on fuel gas) and gentle particle heating lead to minimal feedstock phase transformation and almost non-existent elemental depletion/decomposition of the in-flight particle.

Furthermore, the replacement of pure oxygen in the HVOF process by using air in the HVAF process significantly reduces the oxide content in the coatings, which is desirable for high-performance coatings.

Background

A manufacturer had a mission-critical titanium part in a new product which contained two OD seal surfaces. The use condition subjected the part to fully reversing hydraulic pressure cycles of 5 KSI (with occasional spikes to 8 KSI).

Note: An NDA covers this application and our relationship with this customer, so, for this reason, details are intentionally vague. This report has been reviewed, edited, and approved by the customer for our use.

Customer Initial Requirements

  • The seal surfaces should not experience excessive wear over the service life of the part.
  • The seals themselves should not be negatively affected due to the reciprocating motion while in contact with the part.
  • Application of the coating should not affect the substrate material properties. In particular, it should not cause heating which would result in the formation of beta phase within the Ti crystalline structure.
  • The coating should not be cost prohibitive.

Initial Customer Testing

Customer performed testing which simulated operational conditions over a period of several months.

Preliminary Customer Results

Parts exhibited longitudinal cracks through the coating which formed a stress concentration resulting in crack propagation through the titanium alloy substrate. Once cracks progressed through the substrate, this created a passage between two isolated fluid circuits, rendering the equipment unfit for continued use. Fatigue life was on the order of 2e5 cycles – far below the expected infinite fatigue life. These failures prompted the customer to specify an additional performance requirement.

Additional Customer Requirements

Application of the coating should not cause a fatigue debit.

Kermetico Recommendation for Coating Thickness

After discussions with the customer, Kermetico recommended reducing the layer thickness from 250 microns (.010”) to 65-80 microns (0.0025”-0.0035”).

Customer Development Efforts

In addition to Kermetico’s recommendation, the customer pursued the addition of a shot-peening process prior to the application of the WC-Co-Cr coating as well as modifications to the machining and finishing processes.

Kermetico Responsiveness

The customer ordered some variants in preparation to test the effect of modifying dimensional and process parameters. Knowing the criticality of the parts, we completed the turnaround time of our processing in a matter of days.

Customer Development Testing

Fatigue testing under worst-case loading conditions, as well as seal endurance testing, was performed over the course of roughly a 12-month period.

Customer Hard Chrome Replacement Results

Fatigue testing exhibited a fatigue life more than 10e7 cycles. As this number of cycles is more than the published endurance limit for the substrate material at the stress ratio experienced by the parts, testing was halted with the expectation of infinite fatigue life. One of these two designs was adopted for production and subsequently placed into service. As of this writing, no field failures using the updated part design have been reported.

Other Hard Chrome Plating Alternatives

Numerous studies of Kermetico HVAF sprayed Fe-based coatings have shown their high corrosion resistance in different environments such as acid, alkaline, and chloride solutions. High-quality microstructures with low oxide content, high retention of the powder chemistry and low porosity have been reported and make this family of coatings suitable as a low-cost hard chrome replacement in many applications.

For more information on HVAF systems, Click Here.


Non-Slip Coatings

The MSSA 28E coating is used for non-slip applications. The incredibly durable non-slip metallic coating has been used on baggage handling ramps and walkways in airports, as well as ferry loading ramps and walkways in a new sporting stadium in the UK. Untreated steel surfaces can become very slippery, especially in wet conditions, and are prone to corrosion. To ensure safe walking and industrial operating conditions, vital to personal safety and corporate productivity, the MSSA 28E coating provides a durable non-slip anti-corrosion coating.

Traditionally, steel structures are hot dip galvanised, or painted, to protect against corrosion. The disadvantage of hot dip galvanising is that the surface can become slippery and it does not easily accept paint without the need for special primers. Painting this type of surface, which is sometimes applied with grit inclusions, also has its disadvantages. The surfaces can degrade quickly in heavy use, resulting in corrosion and an increased slip hazard.

Many large steel structures, including oil platforms, refineries and bridges, have been routinely protected against corrosion by thermal spray aluminium (TSA), zinc or an alloy of the two. While providing unrivalled corrosion protection in very aggressive corrosive environments, pure TSA is not durable enough to prevent long term wear on floor plates. Ideally, steel structures need a durable coating that protects against both slip and corrosion and that’s exactly what the MSSA 28E coating does.

28E is applied using the arc spray process with the ARC 145 system. In the arc spray process the raw material, in the form of a pair of metallic wires, is melted by an electric arc. This molten material is atomised by a cone of compressed air and propelled towards the work piece. Upon contact, the particles flatten onto the surface, freeze and mechanically bond, firstly onto the roughened substrate and then onto each other as the coating thickness is increased. Coating thickness can range from around 50 microns up to several hundred microns or even millimetres for some metals. Typically, metal sprayed corrosion protection coatings vary from 100 to 350 microns.

A 28E coating is a thermally sprayed coating that can be applied with a rough texture and has excellent non-slip properties, while being extremely hard and resistant to wear.

The coating provides:

  • A suitable level of grip to avoid personal slips or industrial skidding.
  • Comparable corrosion protection to aluminium, as used in aggressive environments.
  • Easy application by a long-standing process, covered by international standards.

The resultant coating is corrosion resistant and because of its durability, site owners can be confident that once applied, they can forget about rust or slipping for many years.

This article was published on the Offshore Technology website and is Available Here.


P.T.F.E. Non-Stick Coating

In recent years the advent of the P.T.F.E. non-stick surface has created a whole range of products with this highly desirable characteristic. The average person probably encounters this type of surface in simple kitchen utensils, but there are numerous industrial applications of the same process. 

The application of the P.T.F.E. coatings has been the core of the whole development and for some time, Metallisation has been working with various manufacturers in the Industry. One of the main problems has been to provide the correct key on the metal surface for the subsequent application of the P.T.F.E. non-stick coating. The most suitable way of obtaining such a coat is to provide a non-continuous deposit of sprayed aluminium oxide particles or other materials either ceramic or metallic. The particles are not in continuous contact as the deposit is comparatively thin, in fact, as little as 25 microns (0.001”). However, it is vitally important that the coating is uniform to ensure the correct performance of the P.T.F.E.

In volume production it has been found necessary to use an automatic plant to ensure uniformity of thickness of the deposit, to deal with large-scale production. Automatic plants of several different designs has been produced to overcome these problems. In one such plant the problem has revolved around spraying on circular discs in pre-production form. Incorporating its own spray booth, the plant consists of two arms with a rotating mechanism at their extremity. Whilst one arm is in the spraying position, the other arm is being loaded or unloaded. Each disc is completed on a fixed time cycle, the arms automatically swinging into the spray area so that the operation of the spray is continuous. 

For more information on Metal Spray equipment or consumables, call us on 07 3823 1004 or email us using our contact form.

Metal Spray Equipment