Single vs Two-Component Grouting Machines: Which Do You Need?
The injection pump you choose shapes which resins you can use and how fast you can work. Here is how single- and two-component machines differ.
An injection job is only as good as the pump pushing the resin. Get the machine wrong and you either can’t reach the pressure you need, or you can’t use the resin chemistry the job calls for. The first big fork in the road is single-component versus two-component.
Single-component machines
A single-component pump moves one ready-to-use resin from the pail to the crack. Most polyurethane and epoxy injection resins for waterproofing are single-component (or pre-mixed), so these pumps cover the majority of jobs.
- How it works: One piston pump draws resin and delivers it through a high-pressure hose and packer.
- Strengths: High pressure (units reach several hundred bar), simple operation, easy flushing.
- Best for: Standard crack injection, curtain grouting, soil stabilisation and most waterproofing work.
If you do general injection work, a robust high-pressure single-component pump is the backbone of your kit.
Two-component machines
A two-component machine meters two separate parts — typically at a fixed ratio such as 1:1 — and mixes them at the nozzle just before injection.
- How it works: Two synchronised pumps deliver each part; a static mixer combines them at the head.
- Strengths: Enables fast-setting, two-part chemistries that must be mixed immediately before use; precise ratio control.
- Best for: Two-component PU systems, fast-reaction leak sealing and jobs needing exact mix ratios.
The trade-off is more complexity, more cleaning (each line must be flushed) and a higher price.
How to decide
Ask three questions:
- What resins will I use? If they are single-component, a single-component pump is all you need. If you plan to run two-part fast-set resins, you need a two-component machine.
- What pressure does the work demand? Deep cracks and high water inflow need high-pressure capability — check the pump’s maximum rating.
- How much volume? High-volume contractors benefit from machines built for continuous duty and easy maintenance.
Don’t overlook the supporting kit
Whichever pump you choose, performance also depends on:
- Hoses and couplers rated for the pressure
- Packers matched to your substrate
- Flushing fluid to clean the system before resin sets inside it
Multi-function electric machines also exist for cementitious grouting and plaster spraying — useful if your work spans both resin and cement grouting.
In short
Single-component for the everyday majority of injection work; two-component when your chemistry demands on-the-fly mixing. Tell us what resins and pressures you work with on WhatsApp and we will point you to the right machine.