Rotor pair for a compression block of a screw machine

A rotor pair for a compressor block of a screw compressor, wherein the rotor pair comprises a secondary rotor that rotates about a first axis and a main rotor that rotates about a second axis, wherein a number of teeth of the main rotor is 5 and a number of teeth of the secondary rotor is 6, wherein a relative profile depth of the secondary rotor

• P
• ⁢
• T
• rel
• =
• r
• ⁢
• k
• 1
• -
• rf
• 1
• r
• ⁢
• k
• 1
• is between 0.44 and 0.495, wherein rk1 is an addendum circle radius drawn around an outer circumference of the secondary rotor and rf1 is a dedendum circle radius starting at a profile base of the secondary rotor, and wherein for a rotor length ratio LHR/a:
• 1.4≤LHR/a≤3.2,
• wherein the rotor length ratio is formed from a ratio of the rotor length LHR of the main rotor and an axis distance a and the rotor length LHR of the main rotor is formed by a distance of a suction-side main-rotor rotor end face to an opposite pressure-side main-rotor rotor end face and, in a transverse sectional view, arc lengths b(r), running inside a tooth of the secondary rotor, of respectively appurtenant concentric circular arcs having a radius rf1<r<rk1 and a common central point defined by the first axis of the secondary rotor, are each delimited by a leading tooth flank FV and a trailing tooth flank FN and the arc lengths b(r) decrease monotonically with increases in the radius r.

A rotor pair for a compressor block of a screw machine, comprising a secondary rotor that rotates about a first axis and a main rotor that rotates about a second axis, wherein a number of teeth of the main rotor is 5 and a number of teeth of the secondary rotor is 6, wherein a relative profile depth of the secondary rotor

• P
• ⁢
• T
• rel
• =
• r
• ⁢
• k
• 1
• -
• rf
• 1
• r
• ⁢
• k
• 1
• is between 0.44 and 0.495 wherein rk1 is an addendum circle radius drawn around an outer circumference of the secondary rotor and rf1 is a dedendum circle radius starting at a profile base of the secondary rotor, wherein a ratio of the axis distance a of the first axis from the second axis and the addendum circle radius rk1
• a
• r
• ⁢
• k
• 1
• is between 1.74 and 1.8, wherein the main rotor is configured with a wrap-around angle ϕHR for which 240°≤ϕHR≤360°, and wherein for a rotor length ratio LHR/a
• 1.4≤LHR/a≤3.2,
• wherein the rotor length ratio is formed from a ratio of a rotor length LHR of the main rotor and the axis distance a and a rotor length LHR of the main rotor is formed by a distance of a suction-side main-rotor rotor end face to an opposite pressure-side main-rotor rotor end face, wherein a transverse sectional configuration of the secondary rotor is executed such that a direction of action of torque which results from a reference pressure on a partial surface of the secondary rotor delimiting a working chamber is directed contrary to a direction of rotation of the secondary rotor.