Patent ID: 7717685

Claim:
A pumping cartridge comprising: a cylinder; and a piston rod constructed and arranged for reciprocating motion with respect to the cylinder, the pumping cartridge including therein a sealing component shaped to include a circumferential, flared sealing flange portion extending away from a portion to which it is attached, of a sealing component support element, such that a first surface of the flared sealing flange portion adjacent to and facing a surface with which it is in sliding contact forms a first angle with respect to the longitudinal axis of the cylinder and a second surface of the flared sealing flange portion facing away from the surface with which it is in sliding contact forms a second angle with respect to the longitudinal axis of the cylinder, where the first angle exceeds 0 degrees, the second angle does not exceed 90 degrees, the second angle exceeds the first angle, and the sealing flange portion of the sealing component is constructed of a non-elastomeric material, the flared sealing portion is essentially irreversibly deformed during sliding motion of the piston rod relative to the cylinder.