1. Quality Control in Straw Production
Yu.Potrebenikov & S.Movchan

2. Straw Welding Machine
11-Jun-18 2

3. New conditions of straw production
mowing welding machine into clean room:
T=(23±1)o, humidity H=(65±5)%, dust control, atm. P -> DB
measurement of Al tape width for each spool, -> DB
daily check the welding machine characteristics: ultrasonic generator amplitude and clock; ultrasonic head pressure
to Al tape; Al tape friction, tension and speed of transport part
flush inert gas of welding region (by ionization gun)
automatically check quality by video chamber simultaneously with welding
cut 2 samples (at the beginning and at the end) and carrying out test by tensile test machine; - > DB
used box for straw transportation and storage
straw ID (bar code?) -> DB
operator name, date and time -> DB
long time test straw (~ 1 month) with overpressure (using nipples)

4. Good Straw Specifications
h Mylar /h Al = 36μm/0.15 μm
diameter, D0 (9.77 ± 0.05) mm
elliptic shape (difference D1 and D2 from D0) ±0.1 mm
seam width (0.6 ± 0.2) mm
seam shape “good”
overpressure test min
cyclic test (dP=0->3bar->0) N=10
straw length (2300 ± 1) mm
Al skin resistance (R) (35 ± 5) Ohm/m
gas leakage (N2 at dP=1.5 bar) < cc/min
straw non straightness (L=2300 mm) ± 1 mm

5. Weld seam visual Quality Control
Optical microscope
Optic zoom - x 60
Good shape
BAD shape
11-Jun-18
fusion

6. Overpressure Quality Control
Test straw at dP=3 Bar and dT=10 min
Straw is OK! if:
1) dP=3 Bar and dT=10 min
2) N=10 cycles
(0->3bar->0/1 min)

7. Gas leak Quality Control
Tested straw is OK:
if pressure drop less than
0.2 mbar per 10 min
at P=1.5 bar overpressure

8. Spare

9. Welding instead of gluing

10. Straw with moving end concept

11. * Straws fully assembling outside chamber on the usual working place.
* O-rings using instead of glue.
* One end of straw is free.
* Anode wires are centering into straws independently from spread in values of the straw diameters (±0.15 mm)
* Straw and anode wire placement precision are not depend by assembling accuracy procedures but the chamber and end plugs produce accuracy only.

12. Straw assembly drawing
Straw with different diameters can be used!

13. The assembled straw at the flanges

14. New method of the straw support

15. Device for straw failure individual protecting