Upgrade an existing extrusion line with a precision melt pump

UPGRADE YOUR EXISTING EXTRUSION LINES WITH PRECISION MELT PUMPS

GREATLY IMPROVE THROUGHPUT STABILITY!

Using PVC? Not a problem! Harrel developed a melt pump for PVC over 10 years ago; probably more PVC is used in Harrel melt pumps than any other polymer.

Can you get the same stability by using a barrier screw? In a word: No. The barrier is an aid to mixing and melting; it does not make the dramatic throughput stability improvement of a melt pump!

Upgrade kit for existing lines

WHAT THE UPGRADE PACKAGE INCLUDES...

A High Precision Gear Pump -- designed and built by Harrel.
A Precision Digital Drive System -- either AC vector or DC motor and digital SCR drive available.
Precision Temperature Controls & Sensors -- designed and built by Harrel.
A Microprocessor Control System -- designed and built by Harrel. Controls differential pressure and integrates operation of the extruder.

WHAT A MELT PUMP DOES FOR YOUR LINE

STABILIZES THROUGHPUT TO 0.1% over any period of time, vs. about 5% -10% for an extruder alone.
INCREASES THROUGHPUT -- Typically 15-25%.
ELIMINATES SURGING. Extruder used alone is susceptable to surging, especially when production rate is high. The gear pump eliminates the surging.
LOWERS MELT TEMPERATURE. Higher efficiency of melt pump means lower melt temperature. Especially important for degradable polymers like PVC.
IMPROVES ENERGY EFFICIENCY. Total energy consumed by melt pump and extruder is less than when extruder is used alone.
STABILIZES EXTRUDATE DIMENSIONS. When constant throughput of melt pump is combined with optional DIGISYNCH synchronization of haul-off speed, extrudate dimensions can be held to extremely close tolerances.
EASILY EXPANDABLE TO TUBETROL-- totally automated closed loop control of all dimensions.

DESCRIPTION OF COMPONENTS

The Melt Pump.The Harrel melt pump is not a unit originally designed for some other application. It was specifically designed for one-on-one service with precision extruders.
Precision helical gears eliminate the "tooth noise" which occurs with spur gear designs. Through-port construction and close fitting flanges eliminate dead spots, where plastic can hang up and degrade. Heating of the polymer is minimized by limiting the maximum speed to about 60 RPM.
Mounting flanges. Ideally all you'd have to do to install a gear pump is to unscrew the die, move it a foot or so, drop in a gear pump, and bolt it back together again. Harrel furnishes mounting flanges to match your extruder and your die, with split clamps to hold it all together, so that's just about easy it is with a Harrel upgrade system!
Gear Reducer. Motor and reducer sit right alongside the extruder on a convenient stand.
Coupling. A double-knuckle coupling accommodates misalignment from the gear pump to the gear reducer. A single screw is all that is required to remove the coupling. A shear pin protects the pump.
Melt Pressure Controller. The Harrel PC-620 synchronizes the extruder speed to the melt pump speed, providing a steady pressure at the pump inlet. It also controls the starting sequence, and includes safety interlocks.
The major source of throughput error in a melt pump is the incidental leakage around the gears. This leakage is proportional, not to the inlet pressure, but rather to the differential pressure across the pump. The Harrel PC-620 stabilizes this differential pressure and thus increases the overall stability of the pump system by a factor of 5 to 8.

Motor and Digital Drive. Either a rugged AC induction motor and vector drive, or a DC motor and Harrel MD-200 Digital SCR drive can be specified. Both are synchronized to a 0.001% crystal reference by an all-digital MC-101 DIGISYNCH drive controller.
Even more useful is the addition of a second DIGISYNCH controller to synchronize the gear pump speed to the puller speed -- an exact synchronization -- 0.000% steady state error. This in turn stabilizes the cross sectional area of the extrudate.

**PRICES**
Model	For extruder	Approx extr lbs/hr	Gear Pump	cc/rev	Approx pump lbs/hr	Pump HP	Base Price*
UG-610A	1"	15	GP-0005	0.5	4	0.5	$24,528
UG-610B			GP-001	1	8	0.75	$24,633
UG-610C			GP-003	3	15	1	$25,088
UG-612A	1 1/4"	30	GP-003	3	24	1	$25,088
UG-612B			GP-005	5	30	1	$25,200
UG-615A	1 1/2"	55	GP-005	5	40	2	$26,072
UG-615B			GP-010	10	55	2	$26,680
UG-620	2	110	GP-020	20	110	3	$31,292
UG-625A	2 1/2	215	GP-020	20	160	3	$31,292
UG-625B			GP-050	50	215	5	$36,235
UG-635A	3 1/2	400	GP-050	50	400	5	$37,408

*Includes melt pump with heaters, drive motor and gear reducer on mounting stand, two PS-301 pressure sensors, and control cabinet with PC-620 differential pressure controller, MC-101 DIGISYNCH digital speed controller, and drive for the melt pump motor.

OPTIONS AND ACCESSORIES FOR ALL SIZES

1. Inlet and outlet flanges to mate melt pump to extruder and die -- .
2. Added price for 3 zones of temperature control -- inlet flange, outlet flange, and melt pump. Includes PID controllers, temperature sensors, and solid state power modules --
3. Added price for a second MC-101 DIGISYNCH controller for synchronization of melt pump RPM to puller RPM -- 0.000% synchronization error. Stabilizes cross sectional area of extrudate -- .
4. DIGITACH digital tachometer for puller drive motor, if required.
....DT-100 for 1/4 - 3 HP -- .
....DT-120 for 5 HP --.
5. Gear pump mounting stand -- where additional support is required to support weight of melt pump and die --
6. PS-301 melt pressure transducers $995.00 ea.

ORDER UPGRADES, OPTIONS, AND ACCESSORIES ON LINE

To order an upgrade system, fill in the form below and click on "submit". Harrel will enter your order and send you an Email or Fax acknowledgement stating engineering data and credit information required, if any. Enter accessories and options as separate items 2, 3, 4,etc.

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