DC casing head are WHI’s straight profile that accepts the DC casing hangers. These units are designed for heavy duty and severe service conditions or where the operator anticipates other factors that may limit the effectiveness of a tapered profile. They are especially useful in high pressure or where casing weight makes it necessary to reduce hoop stresses in the wellhead body. Units are available in nominal flange sizes to 21 1/4" and pressures to 15,000 psi.

DC casing head housings are available with either female threaded or slip-on (weld) lower connections. The slip-on connection housing has a 1/2" NPT test port, which allows testing of the weld integrity. DC casing head spools provide a restricted area packoff in the lower ID profile to isolate annulus pressure and allow for transition to higher pressures in the upper connections. The type WSS secondary seal is standard. The lower flange connection contains a 1/2" NPT test port, which allows positive testing of annulus seals.

Two 2" LP side outlets are standard on all casing head housings to 5000 psi and on 2000 psi casing head spools. Higher pressure rated housings and spools are provided standard with 2 1/16" studded side outlets. Other thread sizes, studded side outlet sizes or extended side outlets are also available. Unless otherwise specified, flanged outlets have internal threads for valve removal control plugs. Threaded outlets can be equipped with valve removal nipples if required.

If the use of a DC wear bushing is anticipated, housings can be furnished with two lock screw assemblies to prevent rotation and bowl wear. Additional lock screws can be provided if tubing or casing mandrel is required. Information on DC wear bushings and running tools is available.

The DC casing head housing can be furnished with a landing base when required. Landing bases are used to distribute suspended tubular loads over a larger surface area and reduce bearing loads on surface pipe.

ID profiles of DC casing heads provide for a bit guide above the lower connection. Profile diameters are based on API minimum restricted bore calculations for the lightest casing weight. The bit guide protects wellbore tubulars while maintaining the greatest casing access. Other bore dimensions are available if required.