The SMP vacuum vessel welds were reinforced to match the specifications on IRH1710 Rev D. In addition a tube stub was added on the side of the vessel for installation of a PRV. The relief valve installed was Accu-Glass 113150, with 2psi setpoint (not the MDC 420036 model specified on IRH1710 Rev D). The drawing will be updated to reflect this.
Welding was performed in the TRIUMF machine shop. A larger capacity forklift was rented to move the vessel back and forth between the shop and the Meson Hall loading bay where the main crane was used to flip the vessel between welds.
After welding the vessel was leak checked using a blank-off plate (helium leak tight). The vessel was then returned to the Target Hall, the top flange IRH1755 was re-installed, and the TCS shield plug was installed on the flange. The vessel was pumped down over the weekend using the SMP vacuum pump, and reached 8mTorr by Monday morning. A helium leak check was performed in the Target Hall: baseline leak rate 0.0E-9 atm-cc/sec, 0.0E-4Torr port pressure, no response to generous helium spray on PRV and around both seal locations for the top flange.
Remaining re-assembly of the SMP will now proceed. |