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DFT-HT is the newest addition to Lawson Hemphill line of Draw Force Testers. The instrument features 1000 meters/minute test speed and 500°C hot air temperature on the running yarn.  It complies with  ASTM D 5344.

The system is Software Controlled to set the required Draw Ratio and Pre-Tension while maintaining constant air test temperature throughout the test. It is equipped with yarn guides that move the yarn in-out of the heater when testing is completed.  For maximum safety, DFT-HT doors remain closed during  the test.

The operator can start the test from either side of machine by pressing Quick Start Blue button or a single keyboard click. When equipped with Automatic or Manual Splice Package Changers, the DFT-HT  operates continuously.

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  • High Speed and High Temperature precision Draw Force Tester with Electronic Drive System

  • Testing Speeds between 20-1000 meters/minute with electronic servo motors

  • Heater Temperature between 25-500°C

  • Real-time Draw Force Measurement for partially oriented yarn under constant extension

  • Software controlled, Electronic Pre-tension applied for the entire duration of the yarn testing

  • Automatic Yarn Guides to move the yarn in and out of the heater after test

  • Continuous operation with Automatic or Manual Splice Yarn Package Changers for maximum  test efficiency

  • Ability to start the test from both sides of  the machine

  • Closed door application for maximum safety

  • Effectively used to test POY, MOY and LOY

  • DFT-HT complies with ASTM D5344




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.

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  • Precision knitting machine with automatic Stitch Control and Draw Force Measurement system

  • Provides a standard knit fabric sample and draw force results on the same POY package at the same time to check the uniformity and the consistency of the POY production quickly and accurately

  • Complies with ASTM D 5344, Standard method for Extension Force of Partially Oriented Yarn

  • Ability knit POY, MOY and LOY yarn samples

  • Non-contact Vapor Heater (max 205°C) and contact Pin heater (max 250°C) are available to test polyester and nylon yarns on the same machine

  • Precision Draw Ratio rolls from 1:1 to 1:3, with increments of 0.05 are available

  • Nine different cylinder sizes to knit yarns from 10d up to 2000d. (Please consult Lawson Hemphill to knit higher or lower denier yarns.)

  • Interchangeable knitting cylinders that can be used in all Lawson Hemphill knitting machines

  • Maintains constant course length with the Yarn Meterhead to ensure uniform loop size

  • Maintains constant tension on the yarn with the Air Servo/Stitch Cam Regulator

  • Features fabric take-up assembly to collect the fabric sample under controlled tension

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