General statement:

The laser drilling facility is for public use. It could be employed by any ESRF staff members or users after a short training period. The machine should be used for the exclusive machining of materials allowed by the ESRF safety group. It includes: Stainless steel, tungsten and Rhenium. A written authorization from the safety group (contact person: Martine Moroni) must be obtained before machining any other materials.

You can dowlaoud the Laser Drill Instructions here.

A special procedure to allow machining of beryllium gaskets is described below:

Machining of Beryllium (Be) gaskets:

The laser drill facility for HAVING holes drilled in toxic materials, Beryllium, requires a written request**.

Beryllium gaskets (Fig.1), to be used during special high pressure experiments with dedicated diamond anvil cells (DAC), such as PANO-DAC (SESS) or (Paderborn-Panoramic DAC) can be provided, if necessary by the SESS-HP**.

1Untitled.jpg

Fig. 1. Beryllium gasket. Outside diameter 5mm, thickness 500micron. Inner diameter 3.5mm, thickness 200micron.

 

Work procedure:

For the laser drilling of Beryllium a special adapter chamber was designed. This to prevent Be-powder polluting the laser drill device, and more important, creating a health risk to all users of this device.

This special chamber is using the same magnetic kinematics mount as the standard laser-drill gaskets holder and therefore does not require any modifications in the present laser drill setup (Fig. 2).

2Untitled.jpg

Fig. 2. Enclosed holder for laser drilling of Be gaskets.

The Be-gasket is usually indented by diamonds with culets of around 350 mkm to the thickness of 20-60 mkm. After an indentation procedure the gasket is placed inside the closed chamber designed for the laser drilling. The enclosure consists of two parts, connected with an SM1 thread (Fig. 3).

3Untitled.jpg

Fig.3.

The bottom part never comes in contact with beryllium and therefore is considered as non-contaminated. The top part containing beryllium gasket is fully sealed (Fig. 4) and will be opened and closed only inside a designated glove-box (now located in the HP-lab of ID-24) approved for Be use. Under these safe conditions the chamber is opened and the gasket should be cleaned with acetone. All the contaminated wastes goes into the special waste container.

4Untitled-2.jpg

Fig. 4. A section view of the sealed part with the Be gasket.

 

1 – Top 4-mm thick sapphire window for the IR laser sealed with the standard lens retaining ring.

2 – Be gasket

3 – Bottom 1-mm thick sapphire window for back illumination, sealed with a cyanoacrylate glue.

4 – Viton O-ring which makes the seal between window and gasket.

When a next gasket is ready for drilling, it has to be brought inside the glove-box, where it is fixed inside a chamber, the chamber is closed and all the outside surfaces are cleaned.

The chamber goes out of the glove-box and can be taken to a laser drill setup. After a hole is drilled, the chamber is returned again inside the glove-box, where it can be opened and cleaned. All Be-contaminated wastes are kept inside this glove-box.

This way of preparation of Be- gasket is much more efficient than that with use of spark-erosion machine, which is much slower and less accurate. Spark erosion also produces much more potentially toxic wastes (petrol, dirty ethanol for cleaning the machine).

The chamber described has been used since 07/2013, recent laboratory tests** (CARSO – Laboratoire santé environment hygiene de Lyon) have showed that no Beryllium parts have been found on and around the sample area.

We can there for conclude that the adapter chamber is completely closed.

* Results Laboratory test done end May 2014

5Untitled.jpg

Note: Estimations of the Be amount removed during the hole drill: Typical gasket hole diameter is ~ 0.12 mm, and typical gasket indentation thickness is ~ 0.03 mm. Total removed material volume is therefore ~3.4x10-7 cm3 that corresponds to = 6.3x10-7g (0.0006 mg) of Be. Laser spot size is about 7 microns in diameter, so the total amount of Be evaporated during laser drilling is ~8.4x10-8 cm3 = 1.5x10-7 g (0.00015 mg) of beryllium.

Used Beryllium: I-70 (contains 99.2% of Be, 0.7% - BeO, 0.06 % - Fe, 0.01% - Al).

 

** Please contact:

By telephone: 04.76.88.2199

Or by mail jeroen.jacobs@esrf.fr

 

The SESS-HP laser drilling facility is located in the SESS-HP-lab, sector 21.0.12&13 (from 09/2014 onwards, now on ID24 HP-lab).

 

Authorised persons to drill Beryllium gaskets :

- Jeroen Jacobs (SESS)

- Innokenty Kantor (ID24)

- Ilya Kupenko (ID18)