Introduction: Two Generations of Industrial Homogenisers
When it comes to high-pressure homogenisation in the dairy, food, beverage, and chemical industries, two machine series frequently come up in equipment selection discussions: the Gaulin MC series and the BOS MG series. Both are proven workhorses, but they represent different eras of engineering and design philosophy.
This article provides a detailed, side-by-side comparison of the two ranges — covering pressure ratings, capacity, CIP compatibility, serviceability, and total cost of ownership. Whether you are operating ageing Gaulin MC machines and considering an upgrade, or evaluating options for a new line, this guide will help you make an informed decision.
Gaulin MC Series — Overview
The Gaulin MC series has been a staple in industrial homogenisation for decades. Originally developed by APV Gaulin (later acquired by SPX FLOW), the MC range was designed for medium- to high-capacity applications in dairy processing, beverage production, and chemical emulsification.
Key characteristics of the Gaulin MC series include a robust cast-iron or stainless steel frame, a crankshaft-driven plunger pump, and a two-stage homogenising valve assembly. The MC models range from approximately 500 l/h to 60,000+ l/h, with operating pressures typically between 150 and 400 bar (2,175–5,800 psi). CIP (Clean-in-Place) capability is available on most models, though older MC units may require manual disassembly for thorough cleaning of certain components.
While the MC series is well-regarded for its durability, many units still in operation today are 15–30 years old. Original Gaulin spare parts are becoming harder to source through OEM channels, and lead times have increased significantly. This is where compatible aftermarket parts and alternative machine ranges become relevant.
BOS MG Series — Overview
The BOS MG series represents the latest generation of industrial homogenisers, designed and manufactured by BOS Homogenisers in the Netherlands. The MG range covers a broad spectrum from laboratory-scale units to large-scale production machines:
- MG2 — Entry-level, ideal for pilot plants and small-batch production
- MG3 — Compact design for medium-duty applications
- MG4 — Versatile mid-range homogeniser
- MG12 — High-capacity single-stage option
- MG14 — Enhanced pressure capability for demanding applications
- MG18 — Industrial workhorse for continuous production
- MG30 — High-throughput for large dairy and beverage lines
- MG45 — Heavy-duty, high-pressure capability
- MG120 — Maximum capacity for the largest production facilities
- MG124 — Extended range variant of the MG120
- MG140 — Top-of-range, ultra-high capacity homogeniser
The MG series features modern CNC-machined forged stainless steel cylinder blocks, precision-ground plungers, and a modular valve assembly designed for rapid changeover and full CIP compatibility. Operating pressures range from 200 to 600+ bar depending on the model, with capacities from 50 l/h up to 80,000 l/h.
Head-to-Head Comparison: MC vs MG
Operating Pressure
The Gaulin MC series typically maxes out at 400 bar (5,800 psi) on standard models. The BOS MG series pushes this significantly further, with several models rated for 600+ bar (8,700 psi). For applications requiring ultra-high pressure — such as cell disruption, nano-emulsions, or pharmaceutical processing — the MG series offers a clear advantage without requiring a specialised machine.
Capacity Range
Both series cover a similar overall capacity range (approximately 500–60,000+ l/h for typical industrial models). However, the MG series extends further at both ends of the spectrum: the MG2 handles very low volumes for R&D and pilot work, while the MG140 reaches capacities exceeding 80,000 l/h for the largest production lines.
CIP Compatibility
Full CIP compatibility is standard on all BOS MG models. The homogenising valve assembly, cylinder block, and all product-contact surfaces are designed for automated cleaning without disassembly. Older Gaulin MC units may have limitations in CIP performance — particularly around the packing area, valve seats, and cylinder block connections — often requiring partial disassembly for hygienic cleaning to modern standards.
Cylinder Block Design
The Gaulin MC uses cast or forged cylinder blocks that have proven durable but can develop issues such as scoring, corrosion, and pressure leakage over time — especially in units with 15+ years of service. The BOS MG series uses exclusively forged stainless steel cylinder blocks, CNC-machined to tight tolerances, which offer superior corrosion resistance and longer service life. Read more about homogeniser cylinder blocks and maintenance best practices.
Spare Parts Availability
This is a critical consideration for MC operators. As the Gaulin brand has changed ownership multiple times (APV → SPX FLOW → various), the supply chain for original MC parts has become fragmented. BOS Homogenisers addresses this directly by manufacturing compatible Gaulin cylinder blocks, plunger rings, springs, drive shaft seals, and baffle seals to OEM specifications.
For the MG series, all spare parts are manufactured in-house and available from stock, with over 15,000 parts in the warehouse at any given time.
Serviceability and Maintenance
The MG series was designed with serviceability in mind. The modular construction allows technicians to replace valve assemblies, plungers, and seals without removing the cylinder block from the machine. This reduces downtime during routine maintenance from hours to minutes in many cases.
When to Choose Each Series
Consider the Gaulin MC if:
You already operate MC machines with years of remaining service life, your application requirements fall within the MC’s pressure and capacity envelope, and you have a reliable supply of compatible spare parts. BOS Homogenisers can support your existing MC fleet with instrumentation, hydraulic components, and all wearing parts.
Consider the BOS MG if:
You need higher pressure capability (400–600+ bar), require full CIP compliance to current hygienic design standards, want to reduce maintenance downtime with modular construction, are planning a new installation or line expansion, or your existing MC machines are reaching end-of-life and you want a modern, fully supported replacement with guaranteed parts availability.
BOS as Your Transition Partner
BOS Homogenisers occupies a unique position in the market: the company both manufactures the MG series and supplies aftermarket parts for Gaulin, APV, SPX, and Rannie machines. This means BOS can support your existing fleet today while helping you plan a smooth transition to newer equipment when the time comes.
Whether you need actuator packings, gaskets, or a complete plunger packing set for your Gaulin MC, or you are ready to discuss a new MG installation, BOS has the expertise and inventory to keep your production running.
Get Expert Advice
Choosing between maintaining your current Gaulin MC homogeniser and upgrading to a BOS MG is a significant decision that depends on your specific production requirements, budget, and long-term plans. Our engineering team can provide a detailed assessment of your current equipment, recommend the most cost-effective path forward, and supply parts for any brand of homogeniser.
Contact BOS Homogenisers for a no-obligation consultation, spare parts quotation, or to schedule a site assessment.
Disclaimer: This article is provided for informational purposes only. Specifications mentioned are approximate and based on publicly available data. Gaulin and SPX are registered trademarks of their respective owners. BOS Homogenisers is an independent manufacturer and spare parts supplier and is not affiliated with SPX FLOW or its subsidiaries. Always consult the original equipment manufacturer’s documentation for exact specifications and maintenance procedures.