26/06/23

This morning the pressure was 4e-7 mbar. The bolts on the windows and the large flange on the bottom of the interaction chamber were tightend. No leak was present on the windows following tightening. However, the leak on the rotatable flange, although decreased in magnitude, was still in the 1e-9 mbar l/s range when helium was sprayed. The torque on these bolts was 36 Nm, which is already past the 33 Nm recommendation for M8 bolts. It was decided to vent the section and examine the flange. 

Tomorrow morning the gasket will be replaced and we will begin pumping again in the afternoon. 

27/06/23

Flange was removed and examined. Several scratches on the surface of the flange including on the knife edge were visible. These scratches were sanded away by the grossmontage and the flange was remounted. CARME was pumped down in the afternoon. Pressure was in the 1.5E-3 mbar range when the scroll pump stalled causing the pressure to increase and the turbo to increase in current to keep up. Error symbol was observed on the scroll, unknown to why it stalled. VAT gate valve to the chamber was closed and all pumps turned off to be safe, P~ 1mbar. 

28/06/23

Jan started the scroll pump on  just the backing line using the gas balast to see if too much water was pumped. Scroll running fine so the gate valve to the chamber was opened and the turbo started.