| Client name | City | Country |
|---|---|---|
| Stamicarbon BV | Sittard | Netherlands |
| Standard Fasel Lentjes B.V. | Utrecht | Netherlands |
| Standardkessel Baumgarte GmbH | Bielefeld | Germany |
| Standardkessel Baumgarte GmbH | Mülheim an der Ruhr | Germany |
| STAR RAFINERI A.S. | Sariyer, ISTANBUL | Turkey |
| State Enterprise Research a. Design Inst. of Ch. Eng. | Severodonetsk | Ukraine |
| STEAG GmbH | Duisburg | Germany |
| Steinmüller Babcock Environment GmbH | Gummersbach | Germany |
| Steinmüller Rompf GmbH & Co | Gummersbach | Germany |
| Stevens Engineering Emmen bv | Emmen | Netherlands |
| Stickstoff Werke AG | Lutherstadt Wittenberg | Germany |
| STOLCO | Düsseldorf | Germany |
| Stork Energy | Hengelo | Netherlands |
| Stork Industry Services BV Zuidoost | Elsloo | Netherlands |
| Stork Thermeq B.V. | Hengelo | Netherlands |
| Süd-Chemie AG | Moosburg | Germany |
| Sulzer Chemtech Ltd | Winterthur | Switzerland |
| SUMINISTRO DE INSTRUMENTOS Y ELEMENTOS DE MONTAJE, S.A. | Barcelona | Spain |
| Sun Chemical | Newport | United States |
| Sunvic Regler GmbH | Solingen | Germany |
| Suqian Unitechem | SUQIAN CITY, JIANGSU PROVINCE | China |
| Sur-Tech Instruments Ltd. | Thetford | United Kingdom |
| SUSTEC Schwarze Pumpe GmbH | Spreetal/Spreewitz | Germany |
| Suzhik Flow Control Pvt. Ltd. | Ahmedabad | India |
| Suzhou Delan Energy Science & Technology Co., Ltd. | Suzhou | China |