The THREADFORMER for a New Twist in Unscrewing Devices for Molds
The Threadformer Unscrewing devices are precise, sturdy and cost-efficient
• Powerful hydraulic motor for rapid and unscrewing action
• Repeatable precise core stopping ability within .003” or better.
• Compact single, twin, right angle, mini, and multi unit drive unit designs
• Supports long thread depths, pitches, and types
• Requires minimal maintenance for high production use
• Retrofittable for new or existing injection molds
• Demolds both right and left-hand threads
The EXAflow Threadformer is supplied ready for operation. The fixed thread guide nut comes with factory-machined internal threads matching the pitch of the thread to be molded. Three powerful hydraulic motors to choose from, which can deliver up to 2,450 rpm. Single-drive unit mounts to mold using two M10 SHCS. For twin-drive units, two M10 mounting screws are required. 24 volt DC high precision proximity switches are included for hydraulic control. All steel parts are hardened and ground with the core holder nitrided for extra wear-resistance.
THREAD CORE MOUNTING
Simply install core in core nut and secure with two set screws. The thread core mounts in the core holder via a common 16 mm dia. shank system. Moldmakers need to fabricate their own thread core defining the geometry of the mold-in thread. Pitch should include shrinkage.
POSITIONING - A Brief Review
To guarantee a precise thread start position, the core holder must run against a fixed stop with its entire front surface area at a pressure not exceeding 40 bar. The flow of hydraulic fluid must be shut off by use of a proximity switch slightly before the core holder touches the fixed stop. For the core holder retraction movement, the unscrewing pressure must be higher than the screw-in pressure. However, the unscrewing pressure should not be higher than 100 bar. The retraction of the core holder must again be stopped by a proximity switch. This will involve some after running. Care should be taken to ensure that the core holder does not run up against a fixed stop at this point. In case this has happened, the core holder must be released manually. With through-thread, note that the core holder must not touch but should have up to 0,02 mm clearance upon reaching the thread start position. This amount of play will not result in melt film formation.
A hole in the CORE SHAFT allows diverse molding options like - upstanding cores, core cooling tubes or blowing needles for making bottles or containers.
CORE COOLING and
For use at elevated mold temperatures above 70 C or 158 F, matching heat insulation plates and coolable baseplates are available for EXAFLOW Threadformer units. (Coolant connection nipples not furnished.)
"NTGA" type compact unscrewing device shows its merits in two molding applications. The upstanding cores (marked red) are passed through the telescopic sleeve and secured against turning behind the unscrewing device. Unique thru-hole is ideal for threaded core cooling. (marked blue). Right Angle units can be ejector or edge mounted.