is a normally closed two position two way valve the valve 10 is sometimes referred to as a u201c cartridge u201d type valve because it is often manufactured in the configuration of fig1 and it is slipped into a valve chamber in the body of a downhole tool the downhole tool typically have u2014 or more dirty fluid valves to test wellbore fluids at different well depths each valve 10 is in fluid communication with the wellbore and a sample collection bottle to hold wellbore fluids the valve 10 is typically rated for operational pressures of up to 30 000 psi and temperatures of up to 350 u00b0 f the valve 10 has a generally cylindrical body 12 which defines a longitudinal bore 14 which is sized and arranged to receive a seal carrier 16 the seal carrier moves from a normally closed position shown in fig1 to an open position shown in fig2 the body 12 has threads 18 formed on one end to threadably engage the cap 20 a cylinder cover 22 surrounds a portion of the body 12 the cylinder cover 22 is rotationally held in place on the body by a set screw 24 and longitudinally in place by cap 20 the body 12 defines an open pilot port 26 which is in fluid communication with.