Brand: Williams
Williams Pneumatic Metering Pumps for High-Pressure Chemical Injection
Updated: 2026-10-28
Explore Williams micro-injection, V Series dual-seal plungers, pneumatic pulse control and WILROY hydraulic diaphragm pumps, with selection and replacement guidance.
Selection support
- Share flow rate, pressure, medium, temperature and material requirements.
- We can support pump selection, dosing package configuration and spare parts matching.
- Detailed English datasheets and quotations are available for priority models on request.
Technical details
Shown: Williams V Series CP125V125 micro-injection pump. Image: manufacturer. Other series use different configurations.
Williams brings small-dose injection, high back pressure and pneumatic control together.For concentrated chemicals and existing pneumatic installations, selection goes beyond rated flow: displacement per stroke, control interfaces and liquid-end construction matter.
Micro-injection at high pressure
The manufacturer describes CP125V125 micro-injection capability down to 0.025 mL per stroke and pressures up to 8,000 psig (552 barg). Where the process permits neat chemicals, small-dose injection can reduce the need to dilute a chemical simply to accommodate pump capacity. Confirm displacement at the actual pressure, stroke setting and supply conditions. See the manufacturer's micro-injection explanation.
Pneumatic timing and stroke control
An Oscillamatic controller cycles supply and exhaust to pulse the pump or relay. In a pneumatic timer configuration, basic drive and timing do not require an electric motor. This is useful when retaining a pneumatic control arrangement with a suitable supply. Remote automation requires the appropriate control unit and interfaces. See Williams pneumatic controllers.
V Series: dual-seal plunger construction
The V Series brochure describes primary and secondary seals, a lubrication chamber, and a port after the secondary seal for leakage indication or collection. These features make seal compatibility and leakage handling part of the selection discussion. A dual-seal plunger is different from a double diaphragm and is not a zero-leakage guarantee. See the official V Series brochure, PDF page 2.
WILROY: pneumatic drive with hydraulic diaphragm isolation
WILROY transfers drive force hydraulically and isolates the process liquid with a diaphragm. Hydraulic bypass adjusts displacement; double-diaphragm leak detection is an option to evaluate. Some pneumatic and drive components are shared with the V Series, but interchangeability requires model and parts-list checks. See the WILROY product information.
Choose the series around the injection duty
| Series | Construction | Selection focus |
|---|---|---|
| V Series | Dual-seal plunger, including micro-injection models | Small doses, high back pressure, neat chemicals |
| W Series | Packed plunger with pneumatic relay | Larger dosing quantities and batch injection |
| WILROY | Pneumatic-hydraulic diaphragm, bypass adjustment | High-pressure injection with chemical isolation |
| CLD | Pneumatic low-pressure diaphragm | Low-pressure dosing with chemical isolation |
Do not combine one model's maximum pressure with another's maximum flow. Consult the official V Series, W Series and CLD information.
Replacing an installed pump requires an interface review
For an existing Williams installation, review the controller, relay, supply capacity, mounting, connections, minimum stable dose and spare parts together. A different pump may require changes to these interfaces even when nominal flow and pressure match.
- New duties: chemical, concentration, temperature, flow and injection-pressure ranges, supply pressure and available gas flow.
- Installation: the V Series brochure specifies flooded suction; also check filtration, supply conditioning and exhaust routing.
- Replacements: full model, serial number, nameplate, controller and relay identification, existing part numbers and symptoms.
- Project requirements: area classification, permitted drive gas, exhaust conditions and configuration-specific certification.
Send your duty or installed-equipment details to discuss Williams selection and spare parts. Continue with the metering pump guide or dosing package requirements.
Manufacturer information reviewed: 2026-10-28. Confirm performance, materials, control options and documentation against the selected model and agreed technical specification.