SSI Series II High-Pressure Solvent Delivery Pump (Single-Piston HPLC Pump)
| Brand | SSI |
|---|---|
| Model | Series II |
| Flow Range | 0.001–5 mL/min, 0.01–10 mL/min, or 0.1–40 mL/min |
| Maximum Pressure | 6000 psi (316 SS), 5000 psi (PEEK), 1500 psi (low-pressure configuration) |
| Flow Accuracy | ±2% |
| Flow Precision | ≤0.2% RSD |
| Pulse Damping | Integrated low-dead-volume pulsation damper |
| Auto-Cleaning System | On-line solvent-driven seal flush with weekly reservoir refill |
| Seal Replacement | Tool-free, completed in <5 minutes |
| Fluidic Path Materials | Selectable 316 stainless steel or PEEK (biocompatible) |
| Remote Interface | RS232 serial communication, analog voltage/frequency input |
| Dimensions | 140 H × 254 W × 432 D mm |
| Weight | 11 kg |
| Power | 115/230 V, 50/60 Hz |
Overview
The SSI Series II High-Pressure Solvent Delivery Pump is a precision-engineered single-piston reciprocating pump designed for reliable, pulse-free mobile phase delivery in analytical and semi-preparative liquid chromatography systems. It operates on the principle of positive displacement, where a precisely actuated piston—driven by a high-resolution digital stepper motor—displaces solvent volume in discrete increments while integrated low-dead-volume pulsation damping ensures continuous, laminar flow without pressure or flow transients. This architecture delivers stable hydraulic output across its full operational range, making it suitable for gradient elution, method transfer, and applications requiring high baseline stability—including UV, fluorescence, and mass spectrometric detection. Its modular fluidic path—available in either electropolished 316 stainless steel or inert PEEK—supports compatibility with aggressive solvents (e.g., THF, DMSO, high-pH aqueous buffers) and bio-sensitive workflows where metal leaching must be avoided.
Key Features
- Three selectable flow ranges: 0.001–5 mL/min (ultra-low-flow analytical), 0.01–10 mL/min (standard HPLC), and 0.1–40 mL/min (semi-preparative scale), each optimized for volumetric accuracy and long-term stability.
- Integrated on-line auto-cleaning system: leverages mobile phase flow to continuously flush the piston seal interface, significantly extending seal life and reducing unscheduled maintenance intervals.
- Tool-free seal replacement: engineered seal cartridge design enables full seal exchange in under five minutes without disassembly tools or alignment fixtures.
- One-touch solvent change protocol: automated purge-fill-degassing sequence minimizes downtime during mobile phase transitions; manual syringe-assisted priming is also supported.
- Dual-material fluidic path: choice between corrosion-resistant 316 stainless steel (for general-purpose organic/aqueous applications) and biocompatible PEEK (for protein, peptide, or ion chromatography where metal ion interference is unacceptable).
- Robust control architecture: RS232 serial interface for bidirectional instrument communication, plus analog voltage/frequency inputs for external flow rate modulation—enabling seamless integration into legacy or custom-built LC platforms.
Sample Compatibility & Compliance
The Series II pump accommodates a broad spectrum of mobile phase chemistries, including acetonitrile/water gradients, acidic or basic aqueous buffers (pH 1–12), halogenated solvents, and viscous modifiers such as glycerol or ethylene glycol (within viscosity limits defined by pump specifications). Its PEEK configuration meets USP Class VI and ISO 10993-5 biocompatibility requirements for contact with biological samples. The pump’s mechanical design and firmware support GLP/GMP environments: audit-trail-capable operation logs (via optional software extension), pressure and flow monitoring outputs, and compliance-ready calibration documentation align with FDA 21 CFR Part 11 data integrity expectations when deployed with validated chromatography data systems (CDS). No regulatory certifications are embedded in the hardware itself; however, the pump’s deterministic behavior and traceable performance metrics facilitate qualification per ASTM E2656 (Standard Guide for Validation of Liquid Chromatography Systems) and ISO/IEC 17025 method validation protocols.
Software & Data Management
While the Series II operates as a stand-alone pump with front-panel keypad control, its RS232 interface enables full remote command execution—including flow rate setpoint, pressure limit, purge cycle initiation, and status query—using ASCII-based SCPI-like syntax. Third-party CDS platforms (e.g., Chromeleon, Empower, OpenLab) can integrate the pump via standard driver libraries or custom scripting. All operational parameters—including elapsed run time, total solvent dispensed, seal flush counter, and fault event timestamps—are accessible via serial query and may be logged externally for trend analysis or audit review. Firmware updates are performed via serial download; no proprietary software installation is required on host PCs. Data export supports CSV-formatted reports compatible with LIMS and electronic lab notebook (ELN) systems.
Applications
- Analytical reversed-phase and HILIC separations requiring sub-mL/min flow stability (e.g., nanoLC coupling, capillary-scale assays).
- Semi-preparative purification of natural products, synthetic intermediates, or oligonucleotides at 5–40 mL/min with consistent retention time reproducibility.
- Ion chromatography with carbonate/bicarbonate eluents, where PEEK-wetted components prevent catalytic degradation and column fouling.
- Method development labs performing cross-platform method transfer between UHPLC, HPLC, and preparative systems due to its wide dynamic flow range and interchangeable fittings.
- Academic and contract research organizations (CROs) prioritizing low cost-of-ownership: minimal consumables (seals only), infrequent maintenance, and direct drop-in replacement capability for aging pumps from major OEMs.
FAQ
What flow ranges are available—and how are they selected?
The Series II is factory-configured for one of three fixed flow ranges: 0.001–5 mL/min, 0.01–10 mL/min, or 0.1–40 mL/min. Selection is made at time of order; range switching requires hardware modification and is not user-adjustable.
Does the pump support gradient mixing?
No—the Series II is a single-channel solvent delivery pump. Gradient formation requires external low-pressure mixing (e.g., using a T-piece and two Series II units) or integration with a dedicated quaternary or ternary gradient module.
Is the auto-cleaning solution hazardous or specialized?
The recommended cleaning solution is deionized water; no additives or surfactants are required. Weekly reservoir replenishment is sufficient for typical usage (≤8 hrs/day, 5 days/week).
Can the pump be operated in constant-pressure mode?
No—it is a constant-flow (volumetric displacement) device. Pressure is a dependent variable determined by column backpressure and system resistance.
What documentation is provided for IQ/OQ/PQ validation?
SSI supplies a Factory Acceptance Test (FAT) report with as-delivered flow accuracy, pressure rating verification, and seal flush functionality confirmation. User-generated IQ/OQ protocols are supported by dimensional drawings, electrical schematics, and material certificates (316 SS or PEEK).
