Garb

Put on a fresh mask, a fresh beard net if applicable, goggles, and a fresh bouffont (hair net)

Put on a relatively fresh lab coat

Put on new gloves; over the lab coat if possible to form a seal

Initial Setup

Assemble washers onto the screws and for through holes, get out the needed number of plate nuts (or non plate nuts if plate nuts don't fit, like for the Agilent TwisTorr 74 Turbo Pump)

Get the flange and a new copper gasket out but keep wrapped in plastic/foil. Inspect the copper gasket for scratches and cleanliness.

Inspect both knife edges of the flanges and check for cleanliness

Cut a large hole in the plastic but do not touch the flange or the gasket

Clean your gloves with isopropanol since you are about to touch vacuum surfaces

For flanges 4.5" or smaller with a horizontal orientation

Put the gasket onto the flange and place the flange on the vacuum chamber

The flange should freely rotate. Rotate the flange so that the holes are aligned, then insert the screw and washer and tighten to finger tight so that the washer doesn't wiggle

Insert a screw and washer onto the other end of the flange and tighten to finger tight so that the washer doesn't wiggle

The flange and gasket should now be secure, but often it is useful to keep upward pressure on the flange to add the rest of the screws and keep everything centered

Add all the screws and tighten to finger tight so that the washers don't wiggle

For flanges 6" or larger with a horizontal orientation

Get a partner who is similarly garbed in case they need to hold something

Hold the flange up to the vacuum chamber and have the partner partially screw in 2 screws at the top of the flange to secure the flange

Add screws to the bottom half of the flange. We are going to tip the flange open, so do not screw in the screws too much

Remove the top two screws

Tip open the flange

Drop in the gasket, making sure its centered and not hitting anything dirty on the way down

Press the flange against the vacuum chamber

Have your partner insert the screw and washer on the top and tighten to finger tight so that the washer doesn't wiggle

Have your partner tighten a bottom screw and tighten to finger tight so that the washer doesn't wiggle

Add the remaining screws and washers and tighten to finger tight so that the washers don't wiggle

For flanges with a vertical orientation

Put the gasket on the vacuum chamber

Put the flange on the gasket

Rotate the flange to align the bolts

Add the screws and washers and tighten to finger tight so that the washers don't wiggle

Tightening

Tighten the bolts in a star pattern until there is (mostly) steel to steel contact

CF 2.75": I use a 2-2-3-2-2 pattern, slowly increasing torque (there are 6 total)

CF 4.5": tighten every 3 screws (there are 8 total)

CF 6": tighten every 5 screws (there are 16 total)

CF 8": tighten every 7 screws (there are 20 total)

CF 10": tighten every 7 screws (there are 24 total)

Cleaning

For cleaning in vacuum, use the Pre-wetted Vectra Wipes (Alpha Red Wet) which are 100% isopropanol. Water is very bad

For cleaning outside vacuum (which is worthwhile to avoid getting contamination in vacuum, use a non-shedding wipe and acetone (great for tape) or isopropanol

Water can be used once the inside of the vacuum isn't exposed

Necessary Torque

Flange Size	Thru Holes	Blind Holes	Thru Holes Annealed Copper
1.33"	?	?	?
2.75"	14 Nm	18.6-19 Nm	10.7 Nm
3.375"	?	?	?
4.5"	?	27-34 Nm	?
6"	34 Nm	34 Nm	?
8"	20-23 Nm	?	?
10"	?	34 Nm	?