01How product reaches the piston
Gravity works for a pourable lotion. A stiff night cream or body butter needs a pressurised or stirred hopper, or a feed pump, to push product into the cylinder on every stroke. Ask which feed the quote includes and on what viscosity it was proven.
02Piston, rotor pump or servo
A pneumatic piston is simple and cheap. A rotor pump handles very thick paste with less shear. A servo piston lets you change volume on the screen instead of with a hand wheel. Each suits a different product, not a different budget.
03Heated hopper for creams that set
Some creams are filled warm and set in the pot. Without a jacketed hopper and heated lines, the product thickens during a stop and the first fills after restart come out short.
04Nozzle cut-off
Cream strings from the nozzle and lands on the rim or thread. Ask for a nozzle with a shut-off valve and a lift speed you can set.
05Dead volume and cleaning
Cream left in hoppers, valves and hoses is lost at every changeover. Ask how much product the machine holds when empty and whether valves strip without tools.