SPECIAL TOPIC : HOSE ASSEMBLIES
Understanding Hose Assembly
Hoses themselves are not a ready-to-use product . In order to connect a hose to a technique or other aggregate unit , the device must be equipped with a suitable connection . Modern equipment manufacturers offer a fairly large variety of connections , though there is no one universal hose connection that fits every kind of equipment . So , how do you know the kind of equipment necessary for a hose installation ?
By Jurij Artiukhov , General Manager , PipeTime , LLC
High Pressure hose fittings .
Understanding the Basics Just like other manufacturing equipment , there is no one way to ensure a suitable connection for every hose-type . In fact , the choice of connection for a hose must be in accordance with the parameters and dimensions of the counterpart in order to be fully functional . These connections can be selected depending on the speed that is necessary , the duration of time that the hose will be used , whether it is possible to establish the connection manually , and several other factors .
High Pressure Hoses The most commonly used hose technology is high pressure hoses . The choice of connection in these types of application implies an important parameter : resistance to high pressure . Installation , in this case , does not take place manually , but rather mechanically using a special crimping machine .
Standard industrial hose clamps are able to withstand pressures up to 16-32 bar , though in the case of hydraulic hoses , the pressure is an order of magnitude higher . There are several additional challenges in selecting a line of fittings for a high pressure hoses , including : the usage of different metric systems in certain countries , the wide variety of equipment and technology , and other features .
Typically , high pressure hose fittings from different areas of the world differ in seal and thread type , see Chart 1 .
The type of fitting required for a high pressure hose is usually stationary . More specifically , a connection on a high pressure hose will not require additional movement following installation . As the installation of such a connection requires a certain amount of knowhow and skill , trained and qualified personnel are typically required .
If a solid and permanent solution is needed , the hose assembly can be flanged . Given the huge variability of flange standards , there should be few challenges encountered when selecting a flange ; all sizes , the number of holes , and other standards are clearly elaborated by product manufacturers . The manufacture of such a connection takes place , in most cases , using a welding machine and a milling machine . The part of the fitting which is installed inside the hose is welded to the flange itself , and special wave-like notches are made onto the device . Afterward , when the connection is installed on the hose and crimped with clamps , these notches make it possible to exclude the outlet of the fitting from the hose when pressure is applied .
Crimping with clamps for a high pressure hose assembly can be done either manually or using a crimping machine . Such solutions are used where the risk of depressurization is unacceptable ( for example , when pumping oil products ), or it is necessary for the hose to work under pressure for a long time .
Thread Type European ( DIN )
English ( BSP )
American ( SAE ).
Chart 1 : Seal and thread types .
BSP , JIC , JIS - cone seal
DKO-L , DKO-S , SFS , SFL , STECK - ring or cone sealing
DK - sphere seal NPTF , BSPT , NKT - tapered thread seal ORFS - gasket seal Banjo - bolt seal
18 Hose + Coupling World , December 2021