Establishing a fluid process
May 1st 2005 Master Chemical Europe looks at the question of ‘How many cutting fluids do you really need?’
I’s so easy to slip into bad manufacturing practices. By and large they happen over time, progressively increasing costs, reducing quality and eating into your profit margin. The use of machine tool cutting fluids is a good case in point. You start off with maybe two. New machine tool operators join the company with personal preferences for brands X and Y. So to keep them happy, you add those fluids to your stock. Then you buy new capital equipment. The manufacturer insists you use brand Z, type A and you order several barrels of that. Before long your company is using a multitude of different fluids. So is that a problem? Yes, on several fronts. Obviously, the more fluids you use the larger your stock inventory. Paperwork increases exponentially with the number of fluid suppliers you’re dealing with and the different fluid types stocked. The health and safety documentation involved demands particularly close attention. You receive frequent, minimum quantity deliveries from the various suppliers. All this needs to be managed and may even become someone’s full time job.
Clearly labour costs are an important consideration here. But it’s not just increased overheads. By ordering minimum quantities of fluids you do not benefit from volume discounts. It’s always cheaper to buy in bulk and the savings can be quite significant.
The other big problems are cross contamination and confusion. Cutting fluids are formulated to provide a balance between lubrication and cooling. Mixing fluids – even those from the same manufacturer – can change that balance and impair their performance. It can also cause health and safety problems.
Without the efficient management of a wide choice of fluids it is surprisingly easy for operators to take the wrong fluid out of stock. This may be done unwittingly or simply to save piece-work time if the brand the operator wants is at the bottom of the stack and only retrievable by fork-lift! The end result of using the wrong fluid will certainly be inconsistent cutting quality and may even be damaging to the machine tool itself. The materials from which some machining centres are made simply cannot withstand a synthetic, waterbased formulation and require an emulsion with a high oil content.
If you recognise this pattern emerging at your factory you should take steps to correct it as soon as possible. So where do you start? Firstly by looking at all your machine operations and the commonality between them. Disregarding operator preferences, how many fluids do you really need? Obviously there is a massive difference between machining cast iron and aluminium and you will need a specific cutting fluid for each. But between the two you will almost certainly be able to find a universal cutting fluid that will suit most general production requirements.
Most fluid manufacturers have products covering the complete spectrum of requirements. The main differentiators between them is fluid quality and the service they provide. Most will manufacture an exceptionally wide range.
However, while some are formulated for specific applications, the majority are introduced to take account of local environmental regulations across the world and other variables such as water quality.
Talk to most reputable cutting and grinding fluid manufacturers and you will be told that most general requirements can be satisfied by two or three basic fluids.
The other people to talk to are the machine tool builders or suppliers themselves. They will inevitably recommend a particular fluid with the purchase of a new machine and may even go as far as to invalidate the warranty if that instruction is not adhered to. The charitable view is that they only want you to achieve optimal performance from your investment but vested interests cannot be ignored! You have the upper hand here, you are investing a lot of money in a new piece of production equipment and no supplier would risk losing your custom for the sake of dictating which fluid you use.
A round-table discussion between yourself, your machine tool supplier and your chosen fluid provider can easily produce a workable formula to rationalise the fluid types used.
By focussing on why you use certain fluids and how they perform with a view to rationalising their use is also valuable in a wider sense too. All too often, cutting and grinding fluids are considered as an afterthought rather than an essential in the production process.
The quality of the fluid formulation is of course an important factor. So too is maintaining that quality during use. In the same way as you wouldn’t put a cheap oil into a high performance car, metalworking machinery should be afforded the best possible fluids and practices to ensure maximum productivity. This demands the careful control and monitoring of all coolant related variables. There are three vital components here: The choice of high quality bio-resistant fluids to ensure consistent and reliable results; The adoption of an effective and reliable fluid recycling system to address all coolant failure mechanisms; A continuing management commitment. A carefully scheduled and executed machine cleaning procedure should be established, together with other housekeeping and control routines and all meticulously documented The effect of good coolant management is a reduced fluid inventory, the optimism of tool life and the increased productivity of metalworking machinery. It will also reduce or completely eliminate waste disposal problems. Large savings can be achieved year on year, far outstripping the cost of installing and maintaining a coolant management system. More articles from Master Chemical Europe Ltd: | 
