Jet assembly

A jet assembly for the spinning of cellulose fibres in a vertically downwards direction from a solution of cellulose in a solvent, the jet assembly comprising:

• (i) a spinnerette of generally rectangular plan shape and having an outwardly directed flange at and surrounding its upper end, the spinnerette having a lower face having a planar central region with spinning holes therethrough and surrounding the planar central region a lower peripheral region not containing spinning holes,
• (ii) a top housing having at its upper end an aperture to receive a supply of cellulose in a solution and an annular lower clamping face,
• (iii) a bottom metal housing having an upwardly directed clamping face,
• (iv) heating means to heat the bottom metal housing,
• (v) means positively to clamp the top and bottom housings together to seal the spinnerette via its flange to the top housing to provide a heat transfer pathway from the bottom metal housing to the spinnerette, and
• (vi) an annular thermally insulating layer having a thermal conductivity lower than that of the bottom housing the thermally insulating layer extending across the bottom housing and across at least part of at least an outer portion of the lower peripheral region of the spinnerette.

A jet assembly for the spinning of a solution of cellulose in an amine oxide solvent, the jet assembly comprising:

• (i) a spinnerette of rectangular plan form:
• (a) having a horizontal lower face,
• (b) a plurality of spinning holes in said horizontal lower face,
• (c) upwardly directed metal walls around the periphery of said lower face,
• (d) said upwardly extending walls defining an internal chamber for the passage of said solution therethrough,
• (e) an outwardly extending flange at and surrounding the upper end of said upwardly extending walls,
• (ii) a supply line for the supply of said solution to said spinnerette,
• (iii) an upper housing interconnecting said supply line and said spinnerette,
• (iv) means to interconnect said spinnerette and said upper housing,
• (v) thermally insulating material surrounding some at least of said spinnerette and insulating part at least of the lower edge and lower face of said spinnerette,
• (vi) heating means for the spinnerette,
• (vii) said heating means heating the spinnerette via its flange and a bottom housing, the bottom housing being bolted to said top housing and clamping said spinnerette therebetween.

A jet assembly for the spinning of a solution of cellulose in an amine oxide solvent, the jet assembly comprising

• (i) a spinnerette of rectangular plan shape having
• (a) a horizontal aperture plate having a central region,
• (b) a plurality of spinning holes in the central region of said horizontal aperture plate extending through to a lower face thereof,
• (c) an external framework surrounding said horizontal aperture plate and having an underside,
• (d) an outwardly extending flange of rectangular plan shape integral with said external framework,
• (ii) heating means including a metallic heated member,
• (iii) a plurality of mechanical clamping means located around said spinnerette to clamp together said heating means and said flange, and
• (iv) thermal insulating means insulating at least some of the underside of said external framework and said aperture plate, the lower face of the central region of said aperture plate being insulation free.