Lonetti prover tank on wheels
Exporting worldwide Cat. 2026 · Rev 04
Precision instruments · Est. 1960

Precision liquid calibration equipment since 1960.

Prover tanks · Test measures · Water draw systems · Calibration towers · Test benches · MINILAB® vans — built to OIML R117 & API MPMS standards, exported to 47 countries.

1960
Founded in Buenos Aires
47
Countries served worldwide
OIML
R117 / API MPMS certified
304 SS
Standard construction material
03 · Why Lonetti

Sixty-six years of building tanks that don't drift.

Our customers come back because the equipment outlasts the contracts. Custom-built, certified, and serviced by the same shop that delivered Exxon Mobil's first prover in 1960.

01

Custom Manufacturing

Every Lonetti tank is built to your exact specifications. Any capacity, any geometry, any standard.

02

OIML & API Compliance

All products meet OIML R117, API MPMS Ch. 4.4, and NIST Handbook 105-3 requirements.

03

Global Shipping

We export to 47 countries — full crating, certificates of origin, and freight coordination included.

04

Traceable Certification

Calibration certificates issued in coordination with INTI, traceable to international standards.

Certified to
OIML R117API MPMS Ch. 4.4NIST HB 105-3INTIINMETROISO 9001
04 · Get a quote

Ready to configure your calibration system?

Tell our engineering team the application, accuracy class, and applicable standards. We return a configuration and indicative pricing within two business days.

Calibration quotes — Prover tanks, test measures, custom configurations
International shipping — FOB/CIF pricing, documentation, freight coordination
Distributor partnerships — Country exclusivity, training, marketing support

We typically reply within 2 business days

05 · Resources

Technical articles for metrologists and engineers.

In-depth articles on calibration standards, equipment selection, and measurement practice — written by the Lonetti engineering team.

Coming soon
Buyer's guide Apr 28, 2026 · 9 min

How to Select the Right Prover Tank: A Complete Buyer's Guide

Capacity, accuracy class, material specification, and certification — the four decisions that determine whether your prover tank will serve a custody-transfer application.

Coming soon
Technical Apr 14, 2026 · 12 min

API MPMS Chapter 4.4 Explained: What Operators Need to Know

The chapter governing tank prover construction, calibration, and use — translated from standard-speak into practical operator guidance.

Coming soon
Comparison Mar 30, 2026 · 7 min

Water Draw vs. Volumetric Proving: Key Differences

When to use each method, and which Lonetti equipment supports both — written for refinery measurement engineers and meter shop technicians.