For more than 70 years the German company HPM Technologie has been constructing state-of-the-art spray heads for minimal lubrication in high-precision dosing applications for all types of fluids. They can be found in diverse applications, primarily in the metal-processing industry, where they are used for applying liquid cooling lubricants in machining processes. Except for paints, resins and adhesives, virtually any liquids can be sprayed.
The essential advantage of minimal lubrication is the enormous reduction of the lubricant quantities used compared with conventional cooling lubricant systems and concepts. As opposed to conventional flood lubrication or large-area application, processes that use minimal lubrication require only a few millilitres per hour. The minimal application of fluid also reduces the environmental impact, operating costs and system contamination. According to the Bureau of Statistics, cooling lubricant costs make up 8 to 16 % of the total costs in metal machining processes and therefore represent a relevant cost pool that can be significantly reduced by using a modern minimal lubrication system.
To minimise maintenance and maximise user-friendliness, the spray heads at HPM Technologie are supplied with media using connection components from Eisele Pneumatics. The German company has 80 years of experience in high-quality all metal push-in fittings for use with compressed air. But Eisele push-in fittings can also be used for other media, including gases, coolants, vacuum and liquids – even in combination with electrical and electronic signals.
HPM Technologie had already been purchasing components from Eisele on a regular basis for 40 years when the two companies began cooperating in 2006 to develop and improve custom solutions for specific systems and processes. Since 2013 Eisele has been HPM’s primary supplier of connection components.
For supplying the spray heads with lubricant for minimal lubrication, the company uses straight push-in fittings of nickel-plated brass with a release sleeve from Series 14 and 14A of the Eisele BASICLINE. Although the push-in fittings on the spray heads are labelled, Eisele also equips them with a blue-coded aluminium sleeve, which unmistakably shows where to connect the blue tube, eliminating any possibility of an incorrect connection.
The push-in fittings with a release sleeve feature a larger gripping surface for release of the tube as compared with a simple release ring. This is especially advantageous in applications that use oils or cooling lubricants in which components near the drill or milling head – despite the high level of precision – can be covered with a spray medium, for example due to a malfunction of the machine or oversight on the part of the operator. For the smaller spray heads of the LEO series, HPM Technologie uses products from Series 10 of the Eisele BASICLINE. In these straight push-in fittings of black passivated brass the tube is held by a union nut.
In developing the new LEO series, the focus was on a reproducible quantity setting. In the past, the desired spray quantity had to be set by turning the nozzle and then fastening it with a lock nut. With the universal LEO spray head, the spray quantity is set by means of a graduated drum, without the use of tools. This not only makes it possible to check the setting for the quantity at any time, but also to adjust the setting.
Any changes are immediately visible and can be corrected accordingly. For unchanging parameters (fluid, spray and fluid pressure) the quantity is always 100% reproducible. The outgoing supply line is positioned at a 90° angle to the spray head. All spray heads are available separately or as a spray head group. The spray head group for the low-pressure range from 0.5 – 2.5 bar includes air and fluid connections with a check valve for the distributor, with air consumption of 2 – 5.5 l/min.
The most recent spray system, PPJ, features not only advanced components and optimal sizes, but also an innovative design. Independent regulation of the fluid and spray air pressure in the PPJ valve and tank assembly make it possible to achieve outstanding results even with high-viscosity media. It can supply up to six spray heads and is available with three tank sizes for a very space-saving installation.
The advantages of minimal lubrication in processes such as thread cutting or milling are obvious: cooling lubricant consumption is much lower and, when dosed correctly, workpieces and machines require only minimal cleaning. It also eliminates the need for recovery of the cooling lubricant emulsion and chips, as well as disposal of residual matter. Other benefits include higher cutting speeds and a better surface quality.
HPM Technologie develops custom solutions for applications that require other spray heads than the series models. Numerous custom solutions have already been developed for the food industry. Due to the stringent hygiene standards of such applications, stainless steel push-in fittings of the Eisele INOXLINE are used, for example in dosing systems for fine distribution of grease on baking sheets. In connection with all metal push-in fittings from Eisele, spray heads manufactured by HPM Technologie are also used in the printing industry, as well as in aerospace engineering.