STAUFF Construction machinery components - Tough and robust!

fluid · 05 2023 17 Spectrum Coupling under residual pressure At the express request of manufacturers of large demo- lition excavators and other construction and agricultur- al machinery, a new series of QRC-FG flat-face screw- to-connect couplings was developed to connect hy- draulic hoses. The principle of the previous model to connect tubes and hoses that need to withstand ext- reme vibrations and pressure peaks, with screw-to- connect couplings in place of push-to-connect coup- lings, has already proved its worth on the market for a decade. The smooth face side has been retained, drip losses minimised, and the penetration of dirt particles and air into the hydraulic system has been prevented. Stauff designers have now made the most of the poten- tial to improve the product: the new QRCFG range boasts a higher flow rate, and both sides can be easily coupled manually under residual pressure. Saving in- stallation space and time Stauff Multi-Line clamps enable multiple tube or hose lines to be fastened with just a single clamp. This saves installation space and reduces the number of clamps needed plus all mostly metal components used to fasten them. Installation is thus less complex and the weight is reduced. Multi-Line clamps are ideal for use in large hydraulic excavators, road construction machines, tunnel boring machines, open-cast mining equipment or material handling excavators. They are available for two, three, four or six tube or hose lines with identical or different diameters. They are therefore also ideal for the Four hints for users 1 Equip the hydraulic tank with a dessicant air breather Microparticles first need to be filtered out to prevent them from entering the hy- draulic fluid when venting the hydraulic tank. Ventilating filters are used for this. They have a relatively simple design: an air-permeable, replaceable foam element is located in the hydraulic tank cap. The use of dessicant air breathers is recom- mended for construction machinery, which - as their name suggests – adsorb moisture as well as solids, and prevent corrosion processes. Various versions of them are available. The principle is always the same: an initial filter layer separates out the solid particles. The roughly pre- cleaned air flows through a capsule with desiccant before it is then “fine” filtered and lowered into the hydraulic tank. 2 Monitor fluid contamination during operation Hydraulic fluid contamination within a pressure range up to 420 bar can be deter- mined using particle counters. Stauff sup- plies a particle monitor for continuous measurement and analysis. It can be used to automatically determine the degree of contamination in the form of an 8-channel measurement to detect different particle sizes. The status of oil purity is unequivo- cally displayed by a colour-coded display. Corresponding particle limit values can be individually adapted and set using the soft- ware supplied. Portable laser particle coun- ters have been developed specifically for mobile use, and have an internal data memory for around 600 measurements. Stauff also supplies software for the target- ed evaluation of the measured results. The LasPaC II-P is also available in a sturdy plas- tic trolley, which contains all the compo- nents needed for measurement and opera- tion, including a printer, keyboard and bat- tery. 3 Keep an eye on the condition of the filter elements As late as possible, as early as necessary: This is the issue when replacing filter ele- ments in the high- and medium-pressure filters of hydraulic systems. Replacing a fil- ter too early wastes resources and gener- ates unnecessary costs. However, waiting too long risks a loss of performance or even the failure of the hydraulic system. The clogging indicator of the Stauff HI-D-024 provides convenient monitoring of the fil- ter elements. The display has more than just two optical signals – green (everything within the green range) and red (filter sat- uration reached) – and also has a yellow and orange signal. This enables the user to detect at an early stage if the differential pressure is nearing a critical value and can respond accordingly. However, the system can also be automatically switched off if 100% of the differential pressure entered should nonetheless be reached. 4 Fluid care pays off As most failures of hydraulic sys- tems are caused by hydraulic oil contami- nation, it is worth paying particular atten- tion to “fluid care”. This helps to avoid ma- chine downtimes and associated costs, at the same time reducing maintenance cy- cles and installation work. The manufacturer per se is responsible for the “initial cleanliness” of the hydraulic system: OEMs should consider the technical clean- liness of the hydraulic components when selecting their suppliers. Among other things, they should ensure that the com- ponents are free of metallic particles from the manufacturing process. Stauff has put in place measures for every process step from production to storage and transport. The technical cleanliness of its products is guaranteed according to VDA 19 and ISO 16232, a “top cleanliness class” which is only available from other manufacturers at a surcharge. The manufacturer makes a further contri- bution to this by filtering the oil when fill- ing the hydraulic system for the first time. This is because even fresh oil cannot usu- ally be designated as pure. It is rarely fine-filtered during production and pro- cessing, and particles can additionally be introduced during filling, transfer and transport, possibly into reconditioned drums. Stauff supplies diverse auxiliary equip- ment for initial filling and refilling, for ex- ample an oil drum wtransport trolley with offline and bypass filters for internal sup- ply, or a compact, portable filter unit. Multi-Line clamps can be used to fas- ten up to six tubes, hoses or other sup- ply lines.