Metal, tank and steel construction: tanks, special containers and welded structures made of steel and stainless steel, manufactured in Bonaduz, Switzerland
Arno Stiefenhofer AG
Industriestrasse 1, CH-7402 Bonaduz · SwitzerlandNew on Amplifa
About Arno Stiefenhofer AG
Arno Stiefenhofer AG in Bonaduz is a Swiss family business with over 60 years of experience in metal, tank and steel construction. Founded in 1962, the company manufactures cubic and cylindrical tanks, special containers, cold and pellet storage tanks as well as custom welded structures to drawing. The value chain covers consulting, planning, design, sheet metal and profile processing (cutting, plasma cutting, roll bending), submerged-arc welding of large and thick-walled components, delivery, on-site welding and assembly. Production is carried out in structural steel as well as V2A and V4A stainless steel (chromium steel), among other things for water supply applications with high hygienic requirements. Customers come from energy and district heating supply, industry, construction, pharmaceuticals and municipal utilities. On around 3,100 m² of production space in two workshop halls with cranes up to 20 tonnes lifting capacity, one-off productions and small series are manufactured – all production steps take place in Switzerland (Swissmade).
- Site
- CH-7402 Bonaduz
- Processes
- Vessel construction (customized solutions), On-site welding (welding at the installation site), Water supply (components made of chromium steel), Sheet metal processing: cutting, Sheet metal processing: roll bending, Sheet metal processing: welding, Profile processing and special parts to drawing, Small-series and one-off production in steel or chromium steel
- Materials
- Structural steel, V2A stainless steel, V4A stainless steel, Chromium steel, Steel, Submerged-arc welding, Plasma cutting
- Certificates
- DIN EN ISO 9001:2015 (quality management), Welder qualification EN ISO 9606-1, Manufacturer approval, Re-stamping approval, KVU certificate, SVGW certificate, DIN EN ISO 9001:2015, EN ISO 9606-1 (welder qualification), Manufacturer approval Z-COS.VZ.5513348, Re-stamping approval Z-COS.PQ.5513016, KVU certificates (102.004, 103.002, 104.002), SVGW certificate 1001-5668
- Founded
- 1962
- Employees
- 18
- Industries
- Environment/Energy (district heating networks, energy centers, heating plants), Water supply, Municipal utilities, Construction, Industry, Pharmaceuticals
- 01
Consulting and planning
- 02
Design
- 03
Plasma and flame cutting
- 04
Roll bending and profile bending
- 05
Submerged-arc welding / welding
- 06
Delivery
- 07
On-site welding and assembly
- 08
Service
Materials and Processes
Structural steel
Base material for steel construction, welded structures and thick-walled vessels.
V2A stainless steel
Rust-free stainless steel for vessels, apparatus and welded structures.
V4A stainless steel
Corrosion-resistant stainless steel for demanding environments.
Chromium steel
Components for water supply with high hygienic requirements.
Submerged-arc welding
For welding large, thick-walled components with high reproducibility.
Plasma cutting
Precise cutting of sheet metal with high efficiency (system since 2016).
Locations
Bonaduz
CHHeadquarters, production (Hall 1 and Hall 2) and administration
- Lot size
- One-off productions and small series
- Materials
- Structural steel, V2A and V4A stainless steel, chromium steel
- Plasma cutting system
- Submerged-arc welding system
- Roll bending machine
- Profile bending machine
- Flame cutting system
- Indoor overhead cranes up to 20 t lifting capacity
- 70 m long crane runway
Manufactured Components
Inside the production
Industries
Processes & technical limits
| Processes | Tolerance | Max. part | Weight | Lot size | Materials |
|---|---|---|---|---|---|
| Vessel construction (customized solutions)Joining | – | – | – | – | Chromium steel, Structural steel, V2A stainless steel, V4A stainless steel |
| On-site welding (welding at the installation site)Joining | – | – | – | – | Steel, Stainless steel |
| Water supply (components made of chromium steel)Joining | – | – | – | – | Chromium steel |
| Sheet metal processing: cuttingMachining | – | – | – | – | Structural steel, V2A stainless steel, V4A stainless steel, Steel, Chromium steel |
| Sheet metal processing: roll bendingForming | – | – | – | – | Structural steel, V2A stainless steel, V4A stainless steel, Steel, Chromium steel |
| Sheet metal processing: weldingJoining | – | – | – | – | Structural steel, V2A stainless steel, V4A stainless steel, Steel, Chromium steel |
| Profile processing and special parts to drawingForming | – | – | – | – | Structural steel, V2A stainless steel, V4A stainless steel, Steel |
| Small-series and one-off production in steel or chromium steelJoining | – | – | – | – | Steel, Chromium steel |
| Custom welded structures made to measureJoining | – | – | – | – | Structural steel, V2A stainless steel, V4A stainless steel |
| Repairs and modifications to existing metal componentsJoining | – | – | – | – | Metal |
| Special constructionsEngineering | – | – | – | – | Structural steel, V2A stainless steel, V4A stainless steel |
| Metal constructionJoining | – | – | – | – | Structural steel, V2A stainless steel, V4A stainless steel |
| Art objectsJoining | – | – | – | – | Metal |
| Steel constructionJoining | – | – | – | – | Structural steel |
| Submerged-arc welding (of large, thick-walled components)Joining | – | – | – | – | Steel |
| Consulting, planning, design, production, delivery, assembly, serviceEngineering | – | – | – | – | – |
| Visual inspection VT 1 and VT 2Testing | – | – | – | – | – |
11 Anlagen & Maschinen
| Machine | Manufacturer / model | Quantity | Working area | Year built | Site |
|---|---|---|---|---|---|
| Submerged-arc welding system | – | 1 | – | 2015 | Hall 2, Bonaduz |
| Plasma cutting system | – | 1 | – | 2016 | Bonaduz |
| Roll bending machine (new model) | – | 1 | – | 2023 | Hall 1, Bonaduz |
| Profile bending machine (successor model) | – | 1 | – | 2025 | Hall 1, Bonaduz |
| Crane | – | 2 | – | 2023 | Hall 2, Bonaduz |
| Indoor overhead crane (12.5 t lifting capacity) | – | 1 | – | 2018 | Hall 1, Bonaduz |
| Overhead crane (12.5 t lifting capacity) | – | 1 | – | 1984 | Bonaduz |
| Indoor overhead crane (10 t lifting capacity) | – | 2 | – | – | Hall 1 and Hall 2, Bonaduz |
| Indoor overhead crane (3.2 t lifting capacity) | – | 1 | – | 1972 | Hall 2, Bonaduz |
| Indoor overhead crane (2 t lifting capacity) | – | 1 | – | 1969 | Hall 1, Bonaduz |
| Flame cutting system | – | – | – | – | Bonaduz |
Additional services
Reference customers
Approvals and Certificates
Production is carried out according to DIN EN ISO 9001:2015 with certified welders according to EN ISO 9606-1, International Welding Specialist and visual inspection VT 1/VT 2. Manufacturer and re-stamping approvals as well as KVU and SVGW certificates document the standards-compliant execution.
| Evidence | Bonaduz |
|---|---|
| DIN EN ISO 9001:2015 | |
| EN ISO 9606-1 (welder qualification) | |
| Manufacturer approval Z-COS.VZ.5513348 | |
| Re-stamping approval Z-COS.PQ.5513016 | |
| KVU certificates (102.004, 103.002, 104.002) | |
| SVGW certificate 1001-5668 |
Company History
- 1962
Founded as Karl Stiefenhofer & Sohn by Karl and Hugo Stiefenhofer in Bonaduz; started with locksmith work, early specialization in vessel construction.
- 1965
Hugo Stiefenhofer takes over the business as a sole proprietorship.
- 1969
Construction of the first workshop hall (60 × 35 m) with office wing and two indoor overhead cranes (10 t and 2 t).
- 1972
Construction of the second workshop hall (50 × 20 m) with two indoor overhead cranes (10 t and 3.2 t).
- 1979
Expansion of the storage yard with a 70 m long crane runway in the second workshop hall.
- 1984
Additional overhead crane with 12.5 t lifting capacity.
- 1989
Manufacture, transport and assembly of the entire steel structure (350 t) of the GC commercial center in Bonaduz.
- 2010
Conversion of the sole proprietorship Hugo Stiefenhofer into Arno Stiefenhofer AG.
- 2014
Photovoltaic system on the roofs of Hall 1 and Hall 2.
- 2015
New submerged-arc welding system in Hall 2.
- 2016
New plasma cutting system.
- 2018
New crane with 12.5 t lifting capacity in Hall 1.
- 2020
15 employees.
- 2023
Two new cranes (20 t each) for Hall 2; new roll bending machine in Hall 1.
- 2025
18 employees; new profile bending machine in Hall 1.