YDNAC hose clamps are made of double strand steel wire with high resistance; they are coated with a preservative zinc plating, which ensures a practically unlimited durability.
In comparison with other clips and clamps, they have the following advantages:
The stress on the plastic or rubber hose caused by the double strand YDNAC clamps is obviously lower – through the clamping action is the same – than the one caused by the single wire clamps; in fact the radial load is distributed over a wider surface of the hose (see pictures A and B). Furthermore, the roundness of wire of which the YDNAC clamps are made allows the cutting action, when compared with the one produced by the regular boot clamps (see pictures A and C), to be much lower, it ensures a longer durability of the flexible hoses and a higher resistance of blow-off.
General Specification for Ydnac Hose Clips
When the clamp is fitted over a tool gage of dia + B, the length of the two ends must be minus or equal to R, the other major or equal to R. Owing to the oval shape of the clip, the test has to be made with plug gauge with four diameters A,B,C,D – decreasing – whose values are shown on the table.
The following points must be observed:
1. The clip, when opened at it maximum, must be able to run easily over dia. ’A’
2. The clip, after being expanded to dia. ’A’. Must fit with a good roundness, over dia. ’A’.
3. The condition of good roundness is ascertained if, between the clip and the gauge, no cylindrical feeler (calibrated wire) of a prescribed diameter passes.
In order to ascertain that permanent set suffered by material after the assembly be within the prescribed limits for the best working of the clip – this will be fitter on the dia. ’A’ of gauge; then (in free condition the clip must not pass over dia. ’D’ (no-go) of the gauge.
The clips are coated, through the electrolytic process with ZINC, thick ≥8µ as per specs. UNI 4721 (ASTM: A 164-55).
Resistance to corrosion is to be checked in a chamber with salt spray (5% Na Ci) as per specs. UNI 5687-65 (ASTM: B 117-64).
The minimum time of exposure to salt spray before rust marks are apparent in 48 hours.
YDNAC self-tightening clamps to fit flexible hoses subject to low pressure