Registration of incoming material
Close control of incoming materials ensures that they meet the quality demands. Through spot tests and registration of all supplied components a quality sampling of the sub-suppliers and products are made to ensure optimum efficiency and a reliable supply.
The selection of sub-suppliers is based on strict investigations auditing and controls to ensure proven ability to supply materials and services in accordance with the set rules and standards required by AVK. Suppliers must meet the same criteria that applies to all AVK’s production standards.
The components are machined according to drawings with detailed control instructions. Each operator is responsible for spot testing and completion of control papers. The measurement tools are calibrated by an external supplier according to fixed procedures.
Machining of valve stems
The threads are rolled in a separate cold pressing process to maintain the steel structure and increase its strength. Furthermore this method ensures smooth thread edges and consequently low operating torques.
All castings are blast cleaned ensuring that any unevenness in the surface of the castings is fully cleaned. This process ensures optimum adhesion of the coating.
A variety of coatings
AVK offers a number of valve coatings but the majority of valves have, as standard, epoxy coating according to DIN 30677. The epoxy is applied electrostatically in an enclosed booth, where the powder melts and cures on contact with the cleaned and preheated casting. Thorough control of layer thickness, adhesive strength and impact resistance is made to ensure optimum corrosion resistance.
All valves are pressure tested before they leave the factory. The testing is carried out in accordance with DIN 3230, part 4 for water and part 5 for gas. This is the customers´ guarantee for 100% tight valves.
Final inspection and packing
Before dispatch the coating finish and conformity between product and item number is inspected. The valves are packed in wooden pallets with corrugated cardboard carefully placed between the valves to prevent damage of the coating during transportation. For extra protection the valves can be delivered with plastic bonnet and flange protectors.
Traceability in every step
Each valve has a unique serial number allocated after successful production testing which gives complete traceability to the raw materials in the key components along with the manufacturing details.