2. Description
2.1 General Description
Loctite
®
Hysol
®
Bulk-14 Hot Melt System is used for melting and pumping hot melt thermoplastic
adhesives. The system consists of the melt unit, heated supply hose(s), and applicators. System operation is
further enhanced by the use of timers, foot switches, or other controllers. All temperatures in the system are
controlled by closed loop electronics using thermistor-based sensors. This equipment is designed for use
with standard adhesives and sealants such as EVA’s with flashpoints above 232°C (410°F).
2.2 Operating Elements and Connections
1 Melt Unit
The Loctite
®
Hysol
®
Bulk-14 Hot Melt System is able to pump a variety of thermoplastic materials, such as
packaging or product assembly adhesives, wax, and various potting materials. The melt unit consists of a
heated melt tank with a motor-driven, positive-displacement gear pump. The tank has a 14-pound capacity
with an integral melt grid. The tank unit is completely electric; it does not require the use of compressed air
for operation. The wide-mouth design of the tank lid allows use of virtually any form of adhesive, including
granules, flakes, pillows, and blocks. The tank’s integral melt grid transfers heat efficiently from the heaters
to the thermo-plastic material. Temperatures and controls are set from the front panel of the unit through
membrane pushbutton switches. A pressure regulator valve provides fluid pressure regulation by
controlling flow through a bypass mechanism. Additional flow control regulation can also be made through
adjustment of motor speed.
2 Supply Hose
The Loctite
®
Hysol
®
Bulk-14 Hot Melt System supports two hot melt supply hoses. The gear pump has two
outlets to channel adhesive flow to the supply hoses. Temperatures for each hose are individually selected
using the membrane pushbutton switches on the front panel of the melt unit. Both hoses are electrically and
mechanically attached to the melt unit via easy access connectors on the front of the melt unit.
3 Applicator
Applicators used with the Loctite
®
Hysol
®
Bulk-14 Hot Melt System are connected electrically and
mechanically to the supply hoses. Temperatures for each applicator are individually selected using
membrane pushbutton switches on the front panel of the melt unit.
Mounted automatic applicator heads will typically be used in conjunction with a controller, timer, or other
switching device attached to the auxiliary connectors on the melt unit; pump motor switching is also
accomplished automatically via this connection. Handheld applicators are generally used in manual
application systems and possess an integral reed relay switch on the handle grip to control the melt unit
pump motor.
A three position membrane switch on the front panel of the melt unit is used to turn the pump off; allow the
pump to be cycled by a pattern controlling device via the auxiliary connector or by a Handheld Applicator;
or to allow the pump to run continuously.
Selection of the cycle setting results in the motor idling at a crawl speed, rapidly accelerating to the speed
selected by the pump speed indicator when activated, then returning to the crawl speed when the
application of adhesive ends. The motor crawl feature assures constant adhesive pressure in the supply hose
and applicator head, thus assuring a strong stream of adhesive when the applicator is activated.
