The textile industry uses knit-dye-grade or draw force measurement when checking the uniformity of the POY production. Before inspecting the POY for dye uptake, it is necessary first to draw and set the yarn. HDK is the only available lab instrument that offers this capability.

Hot Draw Knitter with Draw Force Tester, HDK-DFT, is a precision knitting machine with automatic stitch control system and a Draw Force measurement to check the consistency of the POY production quickly and accurately. It is ideal for use in production control and R&D labs as well as dyeing plants.

The HDK-DFT is the only instrument that provides a knit sample and draw force results on a package at the same time. This test complies with ASTM D 5344, Standard Method for Extension Force of Partially Oriented Yarn.

POY, MOY and LOY samples from 10d up to 2000d can be knit with the HDK. (Please consult Lawson Hemphill to knit higher or lower denier yarns). The machine can be equipped with a non-contact Vapor heater and contact Pin heater to allow testing of both polyester and nylon yarns. Precision Draw ratios are available from 1:1 to 1:3, with increments of 0.05.

Windows based and user friendly DFT software program provides real-time tension data on the yarn as it is being drawn and knitted. Accept/Reject limits can be defined by the operator. The test results and the tension graphs are saved in common file formats. DFT software includes the ability to run draw force tests under increasing temperature levels to determine optimum settings and critical temperatures for the yarn under test.