A high-pressure fluid pump is operable to pressurize a fluid and includes a hollow stud including a first end, a second end, and a cylindrical space extending between the first end and the second end and a housing fixedly coupled to the first end of the hollow stud. A high pressure cylinder is disposed within the cylindrical space of the hollow stud. The high pressure cylinder includes a bore that extends from a first end to a second end of the high pressure cylinder. A seal head is engaged with the first end of the high pressure cylinder to define a seal therebetween and an end cap is coupled to the second end of the hollow stud and the seal head. The end cap is operable to apply a compressive force to the seal head to compress the seal head against the cylinder and to apply a tensile load to the hollow stud. A plunger is movable within the bore to pressurize the fluid in a space defined by the piston, the seal head, and the high pressure cylinder.