In appropriate lapping movements rib knitting Raschel machines produce two ground fabric lengths which are joined with a spacer thread. The construction of the ground fabric, chosen according to the purpose of the final product, is achieved by combining lapping and threading in such a way as to obtain the desired strength. The yarn material used to join the plain ground fabric at the front side and the plain ground fabric at the back side with a defined “space” is mostly a stable, pressure-tolerant material. A suitable spacer yarn material is usually a polyamide or polyester monofilament. But also glass threads can be used. All other yarn materials can be used as necessary.

The DG 506-15 of LIBA of the well-known rib knitting Raschel series has been developed especially for the production of spacer fabrics. The distance between the two knock-over combs can be set as wide as 15 mm on this newly developed machine. The adjustment range is between 3 mm and 15 mm. This large distance between the knock-over combs and thus between the needle bars is intended for coarse spacer textiles, which is also expressed by the coarse machine gauge of currently E12. The distance between the two ground fabric lengths can be increased further in the finished fabric by using large unterlap shogs such as in the velvet structure.

Applications for such products include:

• Linings of containers, pipes or splash guards of truck wheel housings
• Raw material for T sections and sandwich constructions
• Nets
• Parts of sports shoes
• Medical textiles

The rib knitting Raschel machine DG 506-15 is currently built with a needle stroke of 24 mm. The machine is offered in the working widths 84“ (2130 mm) and 130“ (3300 mm). Machine gauges from E6 to E16 are feasible and imaginable in the future. The new series DG 506-15 is fitted with six guide bars. All guide bars are stitch forming. The circumference of the pattern chain drum is 48 pattern chain links minimum. Either N chain links or pattern wheels are used.

The knitting elements have been designed for coarse textiles. However, coarse textiles do not necessarily mean rugged yarn material. Specially treated “round” links and rounded edges at exposed positions that come into contact with the yarn material allow the use of glass fibre material in all warps. The latch needles used are also adapted to the needs. 
The innovative adjustment of the needle bar - knock-over comb combination is made by a horizontal displacement of the bars in relation to each other and not by the often practised swivel motion that requires a number of subsequent readjustments of all other warp knitting elements.
Good access to the knitting elements for drawing in the warp threads or rethreading is provided by the folding mechanism of the stitch comb. The built-in limit switch prevents the machine from being started inadvertently without the stitch comb folded back into place.

The drive for the knitting elements is equivalent to the proven LIBA design with eccentric shaft and coupler mechanism. All parts run quietly in an oil bath. An oil circulating lubrication supplies lubricant to all bearing points.