N-2640 Series Hydra-Check Dispensers
The N-2640 Series Hydra-Check Dispensers are unique Constant Flow Rate, Positive Piston Displacement, Double Acting metering units. They are used to dispense viscous fluids and pastes with viscosities as high as 3 McP and at pressures up to 3000 psi. They can provide a continuous and constant flow of material that is pressure and temperature compensated. What is unique about these dispensers is that they can do all of this without a hydraulic, electrical or pneumatic power package.
The N-2640 Series Hydra-Check Dispensers include a double acting metering unit that is powered by the fluid pressure of the material supplied to it by the supply pump(s). With supply pressure driving the reciprocating motion of the metering unit, a Heavy Duty Hydraulic cylinder coupled to the metering unit and provided with Pressure and Temperature Compensated Flow Controls provides adjustable but repeatable flow regulation. With the Hydra-Check system, pump stroke change-over surges and material viscosity changes that affect the flow can be eliminated.
The N-2640 Series Hydra-Check Dispensers have a large double acting metering unit with a capacity of nearly 30 in3 per stroke. This ensures low reciprocating rates, which in turn provides long service life. The metering unit utilizes Jesco’s air operated Power Flow Valves for both the Inlet and Outlet Valves to the meter.
The N-2640 Series Hydra-Check Dispensers are systems that are simple to operate and maintain. They are entirely pneumatically controlled and require no more than a standard shop air service to operate.
Many optional features are available for the N-2640 Series Hydra-Check Dispensers. Contact Jesco for details.
N-2990 Series Double Acting Dispensers
The Jesco N-2990 Series Electric Drive Double Acting dispensers were designed to dispense small amounts of low to moderately high viscosity materials. A Stepper Motor Driven Linear Actuator is used to drive 2 Lance type Positive Piston Displacement Meters. The meters are arranged in an opposed fashion such that when one meter is Dispensing, the other meter is Refilling. In this manner, the Double Acting Metering provides a nearly continuous flow of material, thus eliminating the need for Refill time.
Each positive displacement meter has its own set of power operated inlet and outlet flow valves. Both inlets are plumbed together to a common material feed system and both outlets are plumbed together to a common applicator valve. Each metering unit includes its own pressure transducer, allowing the PLC controller to monitor for proper operating conditions in each meter at all times.
These systems are designed to accurately dispense either small repeatable shots or small consistent beads of material at a constant flow rate. Both are adjustable via a thumbwheel on the operator interface. Dispensers are available in 1.8 cc, 7.2 cc and 16.3 cc per stroke displacements in order to better fit the requirements of an application. Shot sizes as small as 0.015 cc per shot can be dispensed. Flow rates as low as 0.015 cc/sec can be dispensed in bead mode.
N-2700 Series Warm Melt Dispensers
The N-2700 Series Warm Melt Dispensers are a series of Constant Flow Rate, Positive Displacement, Piston Metering units designed to melt and dispense warm applied adhesives and sealers directly from 5 gallon pail or 55 gallon drum original material supply containers. Using the time tested and proven Ram Meter Series Dispenser technology, the Warm Melt Series Dispensers integrate all temperature control functions with the dispenser functions into one clean package.
Some of the standard features of the N-2700 Series Warm Melt Dispensers are as follows:
Positive Piston Displacement Metering Unit ensures repeatable volumetric output of shots or beads of material dispensed.
Heavy Duty, Temperature and Pressure Compensated Hydraulic Drive Package provides an adjustable but Constant Flow Rate Dispenser that is capable of delivering repeatable beads or shots of material, independent of material viscosity or fluid pressure variations. Electric Servo Drive package is available as an option.
Heavy Duty, Double Post Elevators are used on both 5 gallon and 55 gallon units to raise and lower metering unit into supply container and maintain forceful contact of heated platen to surface of material for uniform melting. 3” rams are used for 5 gallon elevators and 5 1/2” rams are used on 55 gallon units as standard. For difficult to melt materials, a 6 1/2” ram double post 55 gallon elevator is available as an option.
Material Low Level Warning and controls interlock prevent Reloading on an empty container and thus cavitating the meter.
System Temperature Control is accomplished via 4 independent closed-loop temperature controlled zones. This provides maximum flexibility to material heating requirements. Zones controlled are platen, meter, hose and gun.
PID Temperature Controllers, 1 for each zone, provide precise control of the material temperature even under variable operating conditions.
SCR type Solid-state power relays allow for rapid cycling of power to the heaters for tight temperature control and extended heater life.
High Temperature Limit Controllers, 1 for each zone, provide independent, safety back-up over-temperature protection for the system.
2 Temperature Sensors are provided for each zone for independent, accurate and reliable temperature sensing. Probe type Thermocouples, actually immersed and sensing the material temperature in each zone, are provided for the PID controllers. Surface mount washer thermocouples, attached to the heated parts of each zone, are provided for the Limit controllers. Thermocouples provide rugged and fast responding temperature sensors. RTD sensors are available as an option.
Automatic Temperature Setback feature allows the temperature controllers’ setpoints to be automatically reduced to lower “holding” temperatures whenever material is not being used for a given amount of time. This feature extends the work life of most materials by not heating the material for excessive amounts of time. It also allows the dispenser to heat up and attain working temperature more rapidly than from a cold start.
Automatic Time Lapse Shutdown feature automatically shuts down the system whenever it is left unattended and not used for a selectable amount of time. This feature prevents the system from being left in Setback mode indefinitely and also ensures an automatic and more gradual equipment / material cool-down process.
NEMA 12 rated control panel built to automotive standards (JIC) provides control of all dispenser functions and includes a complete operator interface.
Many options are available for the N-2700 Warm Melt Dispensers. Options such as the Twin Flow System, which provides dual heated metering units that auto-crossover from one metering unit to the other when a material container is emptied. Contact Jesco for further details.