A levelling apparatus for use in gang saws comprises first and second wedge portions. The first wedge portion comprises upper and lower surfaces, wherein the lower surface is nonparallel to the upper surface. The first wedge portion further comprises a plurality of openings for accepting mounting fasteners. The openings are arranged in a spaced, circular pattern about a centre of the first wedge portion. The second wedge portion also comprises upper and lower surfaces, wherein the upper surface is nonparallel to the lower surface. The second wedge portion further also comprises a plurality of openings for accepting the mounting fasteners. The second wedge openings correspond to the first wedge openings. Rotation of the first wedge portion with respect to the second wedge portion varies an angle between the first wedge upper surface and the second wedge lower surface, thereby allowing for angular adjustment.

A levelling apparatus for use in gang saws comprises first and second wedge portions. The first wedge portion comprises upper and lower surfaces, wherein the lower surface is nonparallel to the upper surface. The first wedge portion further comprises a plurality of openings for accepting mounting fasteners. The openings are arranged in a spaced, circular pattern about a centre of the first wedge portion. The second wedge portion also comprises upper and lower surfaces, wherein the upper surface is nonparallel to the lower surface. The second wedge portion further also comprises a plurality of openings for accepting the mounting fasteners. The second wedge openings correspond to the first wedge openings. Rotation of the first wedge portion with respect to the second wedge portion varies an angle between the first wedge upper surface and the second wedge lower surface, thereby allowing for angular adjustment.

A levelling apparatus for use in gang saws comprises first and second wedge portions. The first wedge portion comprises upper and lower surfaces, wherein the lower surface is nonparallel to the upper surface. The first wedge portion further comprises a plurality of openings for accepting mounting fasteners. The openings are arranged in a spaced, circular pattern about a centre of the first wedge portion. The second wedge portion also comprises upper and lower surfaces, wherein the upper surface is nonparallel to the lower surface. The second wedge portion further also comprises a plurality of openings for accepting the mounting fasteners. The second wedge openings correspond to the first wedge openings. Rotation of the first wedge portion with respect to the second wedge portion varies an angle between the first wedge upper surface and the second wedge lower surface, thereby allowing for angular adjustment.

A levelling apparatus for use in gang saws comprises first and second wedge portions. The first wedge portion comprises upper and lower surfaces, wherein the lower surface is nonparallel to the upper surface. The first wedge portion further comprises a plurality of openings for accepting mounting fasteners. The openings are arranged in a spaced, circular pattern about a centre of the first wedge portion. The second wedge portion also comprises upper and lower surfaces, wherein the upper surface is nonparallel to the lower surface. The second wedge portion further also comprises a plurality of openings for accepting the mounting fasteners. The second wedge openings correspond to the first wedge openings. Rotation of the first wedge portion with respect to the second wedge portion varies an angle between the first wedge upper surface and the second wedge lower surface, thereby allowing for angular adjustment.

The embodiments described herein relate generally to improved fit duct liner insulation for curvilinear ducts in HVAC, exhaust, or other similar gas flow systems. A duct liner insulation for a curvilinear duct may include an insulation board having a first major surface and a second major surface. The duct liner insulation further includes a plurality of rows of kerfs in the first major surface of the insulation board configured to allow the insulation board to flex in a direction of the width of the insulation board such that insulation board is foldable into a curvilinear configuration. Each of the kerfs has a v-shaped cross section with sidewalls extending from a kerf base portion at or near the second major surface of the insulation board to the first major surface of the insulation board. The sidewalls extending at an angle from 10 degrees to 20 degrees relative to each other.

A levelling apparatus for use in gang saws comprises first and second wedge portions. The first wedge portion comprises upper and lower surfaces, wherein the lower surface is nonparallel to the upper surface. The first wedge portion further comprises a plurality of openings for accepting mounting fasteners. The openings are arranged in a spaced, circular pattern about a centre of the first wedge portion. The second wedge portion also comprises upper and lower surfaces, wherein the upper surface is nonparallel to the lower surface. The second wedge portion further also comprises a plurality of openings for accepting the mounting fasteners. The second wedge openings correspond to the first wedge openings Rotation of the first wedge portion with respect to the second wedge portion varies an angle between the first wedge upper surface and the second wedge lower surface, thereby allowing for angular adjustment.

A levelling apparatus for use in gang saws comprises first and second wedge portions. The first wedge portion comprises upper and lower surfaces, wherein the lower surface is nonparallel to the upper surface. The first wedge portion further comprises a plurality of openings for accepting mounting fasteners. The openings are arranged in a spaced, circular pattern about a centre of the first wedge portion. The second wedge portion also comprises upper and lower surfaces, wherein the upper surface is nonparallel to the lower surface. The second wedge portion further also comprises a plurality of openings for accepting the mounting fasteners. The second wedge openings correspond to the first wedge openings Rotation of the first wedge portion with respect to the second wedge portion varies an angle between the first wedge upper surface and the second wedge lower surface, thereby allowing for angular adjustment.

The embodiments described herein relate generally to improved fit duct liner insulation for curvilinear ducts in HVAC, exhaust, or other similar gas flow systems. A duct liner insulation for a curvilinear duct may include an insulation board having a first major surface and a second major surface. The duct liner insulation further includes a plurality of rows of kerfs in the first major surface of the insulation board configured to allow the insulation board to flex in a direction of the width of the insulation board such that insulation board is foldable into a curvilinear configuration. Each of the kerfs has a v-shaped cross section with sidewalls extending from a kerf base portion at or near the second major surface of the insulation board to the first major surface of the insulation board. The sidewalls extending at an angle from 10 degrees to 20 degrees relative to each other.

A levelling apparatus for use in gang saws comprises first and second wedge portions. The first wedge portion comprises upper and lower surfaces, wherein the lower surface is nonparallel to the upper surface. The first wedge portion further comprises a plurality of openings for accepting mounting fasteners. The openings are arranged in a spaced, circular pattern about a centre of the first wedge portion. The second wedge portion also comprises upper and lower surfaces, wherein the upper surface is nonparallel to the lower surface. The second wedge portion further also comprises a plurality of openings for accepting the mounting fasteners. The second wedge openings correspond to the first wedge openings Rotation of the first wedge portion with respect to the second wedge portion varies an angle between the first wedge upper surface and the second wedge lower surface, thereby allowing for angular adjustment.

A levelling apparatus for use in gang saws comprises first and second wedge portions. The first wedge portion comprises upper and lower surfaces, wherein the lower surface is nonparallel to the upper surface. The first wedge portion further comprises a plurality of openings for accepting mounting fasteners. The openings are arranged in a spaced, circular pattern about a centre of the first wedge portion. The second wedge portion also comprises upper and lower surfaces, wherein the upper surface is nonparallel to the lower surface. The second wedge portion further also comprises a plurality of openings for accepting the mounting fasteners. The second wedge openings correspond to the first wedge openings Rotation of the first wedge portion with respect to the second wedge portion varies an angle between the first wedge upper surface and the second wedge lower surface, thereby allowing for angular adjustment.