When you're outfitting an industrial pumps flow control setup, the biggest fork in the road is pump design: do you need a peristaltic pump that moves fluid through tubing, or a centrifugal pump driven by an impeller? Your answer affects flow consistency, pressure capability, and the size of your capital outlay. Two strong candidates represent that split: the Cole Parmer Masterflex L/S Process Peristaltic Pump at $1,585, and the Durco Flowserve MK3 STD Chemical Process Centrifugal Pump at $3,750.
Quick verdict
Choose the Cole Parmer Masterflex L/S if you want a 4-channel peristaltic pump for multi-line metering and lower-shear transfer, and you're comfortable with a used unit backed by a 60-day return warranty. It costs $2,165 less than the Durco. Choose the Durco Flowserve MK3 if you need a new open-box chemical process pump with a 275 PSI pressure rating and a bigger centrifugal footprint for continuous process duty.
Comparison
| Pump | Price | Condition | Relative Price | Best For |
|---|---|---|---|---|
| Cole Parmer Masterflex L/S | USD 1,585.00 | Used | Multi-channel metering, low-shear transfer | |
| Durco Flowserve MK3 | USD 3,750.00 | New - Open box | Higher-pressure chemical process transfer |
Where each pump wins
The Masterflex wins on price and pumping flexibility. It uses a 4-channel pumphead, so you can run several tubes at once for dosing or proportional feeding. Its peristaltic action keeps the fluid inside disposable tubing, which simplifies cleanup and protects shear-sensitive media.
The Durco wins on pressure and process readiness. Listed with a 1.5" x 1" connection and a 275 PSI rating at 100°F, it's built for chemical process lines that need to move larger volumes against higher system pressure. It also comes as a new open-box unit, so you're getting unused equipment rather than a used pump.
Product notes
Cole Parmer Masterflex L/S Process Peristaltic Pump
This used peristaltic pump, model 07575-50 with a 7535-04 4-channel pumphead, is a practical entry into precision fluid transfer. The multiple channels are the standout feature: you can dispense into several lines at once, making it a strong fit for metering, dosing, or feeding applications. At $1,585, it leaves you more than $2,000 in budget compared to the Durco, and the seller's 60-day return warranty adds a layer of confidence for a used purchase. The trade-off is that it's used and the listing includes only the pictured components, so you're buying based on the seller's "excellent working used condition" description. For buyers who need multi-channel peristaltic performance at a lower entry price, this is the clear pick.
Durco Flowserve MK3 STD Chemical Process Centrifugal Pump
This is a new open-box centrifugal pump from Flowserve, model MK3 STD, sized 1.5" x 1" with a D4 material designation. It's built for chemical process duty, and the 275 PSI rating at 100°F tells you it can handle higher-pressure lines than a typical peristaltic pump. The $3,750 price reflects both the new-condition status and the larger centrifugal capability. The notable limitation is that the seller states there's no way to test it, though they do offer money back if the pump is dead on arrival. Given that it's 2015 surplus inventory, you're weighing an unused unit against the lack of a live test. If your process calls for a centrifugal chemical pump with this pressure range, the Durco is the one to consider.
Final choice by use case
Pick the Cole Parmer Masterflex L/S for multi-channel metering, gentle fluid handling, and the lower upfront cost. Pick the Durco Flowserve MK3 for higher-pressure chemical process transfer where you want a new open-box centrifugal pump and can absorb the larger investment.
