Expansion Joints - Type MFC | Macoga

Macoga MFC Gimbal Expansion Joints

Macoga MFC are metallic gimbal-type expansion joints with flanged ends. The assembly uses two pairs of hinges on a common floating ring, allowing the bellows to absorb angular movement in any plane. The welded-end equivalent is the MWC series.

Operation and Load Handling

The gimbal ring, hinges, and pins are engineered to absorb pressure thrust and shear loads. As a result, main anchors for pressure thrust are not required, unlike unrestrained axial expansion joints.

Permitted Movements:

• Angular: in one or more planes
• Axial: not permitted
• Lateral: not as a single unit
• Bellows torsion: must be avoided

Typical Applications

MFC joints are used in steam, hot water, thermal oil, flue gas, and process gas pipelines where thermal expansion can be absorbed as angular movement. Common configurations include two gimbal units or two gimbals with one hinged joint, especially where vertical expansion must be controlled via horizontal pipe runs.

MFC vs MWC / MFY / MFK

• MFC: gimbal, flanged, angular movement in any plane.
• MWC: same function with welded ends.
• MFY: double hinged, lateral/angular movement in one plane only.
• MFK: double articulated, lateral movement in any direction, angular in one plane.

Selection Criteria

Selection must verify DN, PN/Class, flange type, pressure, temperature, rotation angle, cycle count, bellows material, internal sleeve, gaskets, pipe weight, and media compatibility.

Installation and Inspection

MFC joints are not intended for misalignment correction. Before installation, check nameplate, flow direction (with internal sleeve), gaskets, bellows cleanliness, and pipe support. Protect bellows from impact, scoring, arc strikes, and weld spatter. Do not suspend by gimbals, hinges, or shipping bars. Remove yellow bars before pressure testing; for hydrostatic tests, use chloride-free water.