Masterflex L/S 77250-62 High-Pressure Peristaltic Pump Head

Overview

The Masterflex L/S 77250-62 is a high-pressure peristaltic pump head engineered for demanding fluid transfer applications requiring elevated backpressure tolerance, chemical resistance, and long-term mechanical stability. Designed exclusively for integration with Masterflex L/S series drive units capable of powering two or more pump heads simultaneously, this model represents the highest-pressure variant within the L/S platform—optimized for continuous operation under system pressures up to 10.3 psi (0.71 bar) when used with compatible high-pressure tubing such as L/S 14HP. Its operating principle relies on positive displacement via sequential compression of elastomeric tubing by stainless steel rollers rotating around a PPS occlusion bed—a design that eliminates fluid contact with moving parts, ensures zero contamination risk, and supports sterile, shear-sensitive, or abrasive media handling without seal wear or leakage concerns.

Key Features

• Maximum pressure capability among all L/S pump heads—rated for sustained operation at up to 10.3 psi (0.71 bar) with L/S 14HP tubing, enabling reliable pumping against elevated system resistance in closed-loop or pressurized manifold configurations.
• Same-side inlet and outlet ports allow flexible installation in space-constrained environments; supports both vertical and horizontal mounting orientations without performance compromise.
• Full stainless steel construction of critical rotating components—including rollers, shaft, rotor disc, and bearings—ensures dimensional stability, corrosion resistance, and extended service life in aggressive chemical environments.
• Occlusion bed fabricated from polyphenylene sulfide (PPS), a high-performance thermoplastic offering exceptional resistance to hydrolysis, halogenated solvents, strong acids and bases, and thermal degradation up to 200°C.
• Backlash-free gear train and precision-machined roller geometry deliver consistent occlusion force across the full speed range (0.02–600 rpm), supporting both ultra-low-flow analytical dosing and high-throughput transfer.
• Non-stackable design—intended for single-head mounting only on dual- or multi-head-capable L/S drives (e.g., L/S 100, L/S 200, L/S 300 series).

Sample Compatibility & Compliance

This pump head is compatible with eight standard L/S tubing sizes: four high-pressure variants (L/S 14HP, 15HP, 16HP, 24HP) and four general-purpose types (L/S 15, 24, 35, 36). Each tubing type exhibits distinct flow-per-revolution characteristics and maximum pressure ratings, allowing users to select optimal combinations based on viscosity, particulate load, and system backpressure requirements. The 77250-82 variant carries ATEX certification (EEx II 3 G c II C T6), permitting safe deployment in Zone 2 hazardous areas where flammable gas atmospheres may occur infrequently and for short durations. While not intrinsically safe, its certified construction meets IEC 60079-0 and EN 60079-15 standards for non-sparking equipment in classified locations. No FDA or USP classification applies directly to the pump head itself; however, when paired with PharMed® BPT or Norprene® tubing, it supports compliance with USP Class VI, EP 3.2.9, and ISO 10993 biocompatibility frameworks in pharmaceutical and bioprocessing applications.

Software & Data Management

As a mechanical pump head, the 77250-62 does not incorporate embedded electronics or firmware. It operates entirely through mechanical coupling to Masterflex L/S drive units, which may feature analog (0–10 VDC, 4–20 mA) or digital (RS-232, USB, Modbus RTU) interfaces depending on model. When integrated with programmable drives such as the L/S 300 or L/S 400 series, users can achieve precise speed control, ramp profiles, total volume dispensing, and event-triggered start/stop functions. Audit trail capabilities—including timestamped speed changes, runtime logging, and error codes—are available only at the drive level and must be enabled in accordance with 21 CFR Part 11 if used in regulated GxP environments. GLP/GMP-compliant validation packages—including IQ/OQ documentation templates and calibration protocols—are provided by Masterflex for qualifying drive-pump head systems.

Applications

• High-backpressure liquid chromatography mobile phase delivery in preparative and process-scale HPLC systems.
• Continuous feeding of viscous reagents (e.g., polymer solutions, slurries, adhesives) into reaction vessels or extrusion lines.
• Pharmaceutical filling operations requiring repeatable volumetric accuracy under variable line resistance.
• Environmental monitoring stations where chemically aggressive sampling fluids (e.g., acidified digestates, seawater extracts) must be transferred without metal ion leaching.
• Bioreactor perfusion systems utilizing sterile, single-use tubing sets with high-pressure-rated elastomers.
• Automated titration and reagent addition modules in analytical instrumentation platforms.

FAQ

Can the 77250-62 be used with any Masterflex L/S drive?
No—it is mechanically and dimensionally compatible only with L/S drive models rated for two or more pump heads (e.g., L/S 100, L/S 200, L/S 300), and must be installed singly (not stacked).

What is the maximum continuous pressure rating for L/S 35 tubing on this pump head?
The L/S 35 tubing is rated for 2.4 bar maximum continuous pressure—significantly lower than the 10.3 psi (0.71 bar) rating achievable with L/S 14HP tubing. Pressure limits are tubing-dependent, not pump-head-dependent.

Is the 77250-62 suitable for food-grade applications?
Yes, when used with FDA-compliant tubing materials (e.g., PharMed BPT or Norprene) and installed in accordance with 21 CFR 177.2600, it meets general food-contact requirements. However, final regulatory acceptance depends on full system validation by the end user.

Does this pump head require periodic recalibration?
No—its performance is governed solely by mechanical geometry and tubing elasticity. Flow accuracy is maintained through consistent tubing selection, proper occlusion adjustment, and adherence to recommended speed and pressure limits.

Can I replace the PPS occlusion bed myself?
No—the occlusion bed is permanently molded into the housing and not field-replaceable. Replacement requires full pump head refurbishment or exchange through authorized service channels.