We all need to look forward not backwards - SED Compliance legislation is here and will apply very soon. How you respond could be critical for your company future: here Guyson review some alternatives.

There has certainly been plenty written recently about 'Solvent Emissions Directive (SED) Compliance' and rumours are rife that we are all going to be prosecuted for cleaning virtually anything, even down to our tea cups! Is it really going to be as bad as that? Of course not, but what many of the articles have failed to mention is the existence of alternatives. Everyone is keen to tell you what you can't do anymore - now Guyson would like to suggest to you a few of these alternatives.

Let's make it plain right from the start: there may have to be compromise and there certainly will be change.

However unpalatable, costly or time consuming the exercise, a line has been drawn in the sand and, with very few exceptions, from 31st October 2007 we will have to change to safer alternatives.

So why not go with it and draw as many positives out of this change as you can?

Such as safer working environments for your employees, less or no harmful emissions, cost savings through reduction of disposal costs, good PR for your company - replacing harmful solvents can be promoted as demonstrating 'best practice' manufacturing.

The solvents affected by the new EC Regulation are Trichloroethylene, Methylene Chloride, Perchloroethylene, n-Propyl Bromide and HCFC (hydrochlorofluorocarbon) solvents such as HCFC 141b.

And everyone has to have complied by the above date, the few temporary exceptions being for the precision cleaning of electrical and other components in aerospace, aeronautics and certain other military applications, for which the ban enters force on 31st December 2008.

CHANGE WORKING PRACTICE TO MINIMISE CLEANING.

There is no going back only forwards so we will start with a simple question: do your parts need to be cleaned?

Is there nothing upstream in the process that can be altered to prevent the parts from being contaminated or reduce that contamination?

Or downstream; can you reduce the number of inter-stage cleaning processes?

Either clean your products less or even clean just once, at the end of the manufacturing process?.

DO YOU HAVE TO USE SOLVENTS TO CLEAN?.

Have you looked at every alternative?

To start with, do your parts actually need to be cleaned with solvents?

If so, there are now SED-compliant cost-effective solvent processes, which we will come to later.

But the answer in some cases is no; you may have simply always done it that way or you may prefer the perceived quality of cleaning - but without actually needing to use solvents.

It is often the case that companies who have a 'trike' tank get into the habit of putting everything through it.

Let's look at the options.

AQUEOUS SPRAY WASH.

There are many safe aqueous alternatives that are perfectly suitable for cleaning a wide range of components.

So why not ring a reputable equipment supplier like Guyson, book some components in for free cleaning trials and take it from there?

You will then know for certain what cleanliness standard can be achieved, and it may surprise you.

The detergent and equipment manufacturers have been working together for many years to produce today's excellent ranges of cleaning products.

Through these cleaning trials, you will hopefully identify that there is at least one alternative technology you can adopt and pursue this further with specific equipment trials to ascertain what type of spray washer you need.

Below, the Allkajet is just one type of aqueous cleaning machine supplied by Guyson.

Model selection will only come about with a full audit of your cleaning requirements, cleanliness specification, throughput volume, total running costs, factory space, budget etc.

Allkajet.

The Guyson Allkajet 600 Rotary Washer delivers high quality cleaning and drying for a wide range of components and is typically used to great effect in batch manufacturing applications in the automotive, aerospace, and medical and defence sectors.

The washing process combines periods of both partial and total submersion with high volume spraying of special low temperature water based solution - pumped at a rate of up to 350 litres per minute at 15 bar pressure - through 14 high-pressure spray jets.

The deluge and turbulence produced completely saturates all component surfaces and penetrates deeply into all awkward recesses and areas normally difficult to reach.

The submerged phase of the operation provides the opportunity to use optional ultrasonic agitation when it is needed to achieve the highest cleaning standards.

At the end of the wash cycle, the cleaning chamber is emptied and flushed out to remove all traces of wash solution.

Rinsing is a repeat of the wash process using a heated rinse solution drawn from its own separate 450-litre tank.

Cycle time is usually shorter for the rinse.

After draining, heated air and blown compressed air are used to dry the components before the component holding baskets are manually removed from the chamber using the integral loading and unloading carriage.

This assists handling outside the machine via the flat folding door, en route to a roller conveyor.

The three-stage cleaning sequence of the Allkajet is PLC controlled and provides wash, rinse and dry options in any combination.

To agitate the components there is a choice between a left and right tilting movement or a continuously revolving tumble-basket at speeds between 0.7 and 1.5 rpm.

Where cleaning volumes are greater, multi module systems are available and a larger model, Allkajet 1200, can accommodate baskets up to 1200mm long in loads of up to 150kg.

Of course aqueous cleaning is not the answer for every component.

Some, such as electronics, PCBs, precision optics, medical and aerospace components may need engineered fluids to provide the high level of cleanliness associated with solvent cleaning.

SOLVENT CLEANING USING HFC OR 3M NOVEC HFE.

Not to be confused with HCFCs (general use of which was banned from 2002), HFC (hydrofluorocarbon) and 3M Novec HFE (hydrofluoroether) do not contain chlorine and do not deplete the ozone layer.

Microsolve ultrasonic cleaning systems.

The Guyson Kerry Microsolve ultrasonic cleaning systems attain the highest cleaning standards yet, crucially, keep running costs low.

Solvent retention features unique to the latest Microsolve machines, including triple coil reflux cooling, vapour break, 150% freeboard, auto top-up and solvent monitoring, ensure the systems are safe and comply fully with environmental and safety legislation.

And as so little solvent is lost, the equipment is extremely cost-effective in use.

Guyson Kerry Microsolve Co-Solvent systems generally provide two cleaning stages, both with ultrasonics and filtration, followed by vapour rinsing and freeboard dry.

In the first cleaning tank a mixture of 3M Novec HFE (Hydrofluoroether) and a hydrocarbon solvating agent, agitated by ultrasonics and the boiling action, removes gross contamination from the components.

Large quantities of soluble contamination can be taken up by the solvating agent, and this makes the process particularly suitable for heavy duty cleaning applications - heavy weight oils, greases, waxes, fluxes etc.

In the second stage, pure HFE distillate, also ultrasonically assisted, removes from the components any residues carried over from the primary cleaning tank.

Cleaning is followed by a rinse in the vapour zone above the tanks and then a dwell in the freeboard zone to dry the components.

Autotrans work transfer systems ensure consistent, repeatable quality whilst increasing throughput, and also contribute to cost reductions by controlling the speed of basket movement through the vapour zone, thus reducing solvent drag-out caused by disturbance of the vapour blanket.

All Autotrans transporters can integrate with feed and exit conveyors or load and unload tables for fully automatic operation.

An optional Primewave generator allows selection of 38, 70, 128 or 194 kHz in both ultrasonic stages, the higher frequency being preferred for certain sensitive component such as electronic components, optical lenses and computer disk drive components to provide effective submicron particle removal.

ULTRASONICS.

Guyson International manufactures a broad range of Kerry branded ultrasonic baths and tanks that cover applications from laboratory bench top to large industrial multi-tank installations.

KS and UCR ultrasonic cleaning tanks.

Typical applications for this range of tanks include production cleaning of machined, extruded, pressed and stamped parts, refurbishment of office equipment, aerospace and automotive engine and gearbox components and maintenance of mould tools, dies, printing components, electronics assembly system parts, food processing machines.

High-end quality cleaning includes printed circuit boards, surgical instruments, and laboratory, medical and dental applications.

These latest KS and UCR (ultrasonic clean and rinse) systems have been designed to achieve optimum cleaning results.

Ultrasonic transducers bonded to the tank base provide high performance and reliability together with uniform distribution of the ultrasonic energy.

The frequency is tuned to the individual tank/transducer combination and then optimised under normal usage conditions with frequency sweep and fully automatic tuning.

Pulsatron KS and UCR tanks allow the user to pre-set exact cleaning times and temperatures, ensuring consistent levels of cleanliness from batch to batch and providing an affordable way to improve cleaning quality.

All functions are controlled by a simple four-button membrane keypad.

An LCD panel displays the temperature and time set by the user, the time elapsed since the start of the cleaning process, and the status of the power supply, heater and ultrasonics.

Each unit works within operating temperatures from 20 to 80 degrees Centigrade which can be set in 1-degree increments, allowing the optimum temperature to be selected for a particular combination of component material, cleaning solution and contaminant.

Sonics time may be set in the range 0.1 up to 99.9 minutes in 0.1 min increments, or to constant when sonics may be switched on and off manually.

Automatic safety devices include non-operation of sonics if solution temperature is more than 10 degrees Centigrade above set temperature, and low-level protection to prevent heater burn-out if solution level drops.

IN CONCLUSION.

We all need to look forward not backwards - the legislation is here and will apply very soon.

How you respond could be critical for your company future.

Guyson has a range of solutions to suit your budgetary and production needs.

As a starting point, apply now for your jargon busting four page PDF leaflet on 'Achieving Compliance with the Solvent Emissions Directive' produced in conjunction with 3M.