Dual Seal Variable Volume Precision Dispense Pump

Pumps

Dual Seal Variable Volume Precision Dispense Pump

This stepper motor-driven positive displacement pump is engineered to reliably control more challenging fluids, including those with high concentrations of surfactants and fluids prone to crystallization, across an extensive cycle life. It utilizes two seals and two fluidic chambers to isolate the motor from the working fluid. The portion of the piston in contact with the working fluid does not retract past the second seal, and the isolation chamber can be plugged with air, filled with a barrier fluid, or actively flushed to dilute fluid residue on the piston. All designs are equipped with a home sensor to establish the end of stroke and an optical motor encoder to provide feedback on piston movement.

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Key Product Facts

Full Dispense Volumes:500 & 1000 µL
Highly Precise:CV ≤0.03%
Home Sensor & Encoder Included on Every Pump
Integrated Backlash Compensation
Port Head Material Options: PMMA or PEEK

Product Information

General Specifications

Characteristic	Specification
Max Dispense Speed¹	2000 Full Steps Per Second
Self Priming	Pumps Operate Across a Wide Pressure Range
Max Discharge Pressure²	30 psig
Operating Temperature	40°F to 150°F (4°C to 66°C)
Storage Conditions³	Temperature: -40°F to 175°F (-40°C to 80°C) Relative Humidity: 85% Max, Non-Condensing

¹Operating the pumps at higher speeds may affect dispense accuracy and life expectancy. The pumps may be operated in full-step, half-step or micro-step mode, depending on the electrical drive design and application parameters. Refer to the individual pump's inspection drawing for additional specifications such as harmonic frequency, etc.
²Varies by pump model. Refer to the part number table for individual pump specifications.
³Pumps should be stored completely wet or completely dried with nitrogen before prolonged periods of inactivity.

Wetted Materials

Component	Material
Port Head Chamber	Port Head: PMMA or PEEK Piston: TZP Primary Seal: UHMWPE
Seal Isolation Chamber	Chamber: PEEK Piston:TZP Primary Seal: UHMWPE Secondary Seal: UHMWPE & 316 Stainless Steel

Electrical Operation

Pumps are equipped with a two-phase bipolar motor.
Home sensors provide a 5 V end of stroke indication; the sensor output will remain low (0 VDC) when the piston is fully extended.
Encoders are two-channel, quadrature (no index pulse) designs.

Cross Section View

Full Isolation Dual Seal Model

Dimensional View

Full Isolation Dual Seal Model
This image is for reference only. All dimensions are in inches [millimeters].

Mounting Details & Port Configuration

There are four ¼-28 flat bottom ports per pump: two in each chamber. The Dual Seal Pump utilizes two seals to isolate the motor from the working fluid. The range of piston movement is shorter than the spacing between the primary and secondary seals, which guarantees no part of the piston in contact with working fluid will ever retract past the second seal. Between the two seals is the seal isolation chamber, which can be used in various ways to prevent crystallization and dilute working fluid residue on the piston. The simplest method is to plug this chamber and leave it full of air. This limits the evaporation of the working fluid residue on the piston, reducing the buildup of harmful crystals. The chamber can also be filled with a barrier fluid and plugged. This prevents crystallization and dilutes surfactants, which eliminates leakage. In the most extreme cases, the seal isolation chamber can be actively flushed with liquid, consistently diluting the working fluid while washing the piston and primary seal.

Part Numbers & Specifications

This table below contains the part numbers and technical specifications for this product. If you have specific questions, need a quote, or would like to request a handbook or drawing, click the red request button in the column on the far right.

Part Numbers & Specifications

PART NUMBER	FULL DISPENSE VOLUME (µL)	FULL STEP DISPENSE RESOLUTION ( µL/STEP)	MAX SPEED (FULL STEPS PER SECOND)	PRECISION: CV 10% TOTAL DISPENSE VOLUME	PRECISION: CV 100% TOTAL DISPENSE VOLUME	DISPENSE ACCURACY AT 100% DISPENSE VOLUME	PORT HEAD MATERIAL	HOME SENSOR	ENCODER	INTEGRATED BACKLASH COMPENSATION	Request Information
LPVA1725350D	500	0.47	2000	≤0.3%	≤0.03%	±0.5%	PMMA	Yes	Yes	Yes	Request
LPVA1755350D	500	0.47	2000	≤0.3%	≤0.03%	±0.5%	PEEK	Yes	Yes	Yes	Request
LPVA1725310H	1000	0.4	2000	≤0.3%	≤0.03%	±0.5%	PMMA	Yes	Yes	Yes	Request
LPVA1755310H	1000	0.4	2000	≤0.3%	≤0.03%	±0.5%	PEEK	Yes	Yes	Yes	Request

CAD Envelopes

Resources

Dispense Pumps Enable Designers to Meet Fluidic Challenges of Evolving IVD Instruments

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Technical Data Sheet

FI Dual Seal Dispense Pump Technical Data Sheet

View Technical Data Sheet

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