High pressure tube unions
Frequently Asked Questions
How does the DILO seal principle function?
It is a seal principle without intermediate tightening compound in form of tongue and groove with little depth of immersion. This principle guarantees permanent tightness at high static and dynamic alternating stresses. Sealing is effected by direct contact with the sealing profiles of the tongue and groove parts.
How to identify DILO unions?
On the face of the clamping nut the following markings can be identified:
- Series and pressure stage (e. g. M1, J1, M2,....)
- Nominal diameter of the union (e. g. 25)
- Material mark (A, C or D)
- DILO logo
- the last 3 digits indicate the batch number of the raw material
Blanking disks are not marked due to risk of damage.
DILO unions are available in 1.0460 (A), 1.4571 (C) or 1.7335 (D) material.
DILO unions can be supplied for precision steel tubes in accordance with DIN EN 10305 and for steel tubes according to DIN EN 10220. If the internal diameters between tube and weld-on stub differ from each other the welding part can be supplied with an adjusted tube wall thickness for aligned laying of tubes.
What are the advantages of DILO high pressure unions?
- DILO unions are used where systems have to be overhauled regularly or where critical operating conditions exist.
- They guarantee a tightness of 1x10-8 mbar x l/s.
- DILO high pressure unions can also be used for all media dependant on the material selected.
- DILO tube unions can be loosened and re-connected as often as desired with the same level of gas tightness
- DILO unions are resistant to vibration without any additional protection.
- Complete interchageability of pieces of the same type is guaranteed.
- Little depth of immersion allows easy assembly and disassembly.
Why are blanking disks necessary and how to assemble them?
Blanking disks are inserted between the weld-on stub part 1 and the weld-on thread stub part 3 or screw in stub part 5 and are tightened by means of the clamping nut. Thus, enabling pressure or leak tests of a plant component without any problems. Blanking disks with borings (throttle disks) can be inserted in order to set the media supply.
Are DILO unions also suited for hydrogen application?
Yes, they are. Thanks to its metallic seal DILO unions are well-suited for hydrogen application. Corresponding references are available. Please contact our sales managers. They will be pleased to offer you a solution for your special application.