What are the delivery conditions for hydraulic steel tubes?

What are the delivery conditions for hydraulic steel tubes ?

Hydraulic steel tubes are delivered in different conditions based on the manufacturing processes and treatment they undergo. The delivery conditions for hydraulic steel tubes can vary depending on the industry standards and specific requirements.

1. Cold finished/hard (BK) hydraulic steel tubes:

This delivery condition indicates that the steel tube has undergone cold working processes, resulting in increased hardness. It is commonly used when higher strength and hardness are required.

2. Cold finished/soft (BKW) hydraulic steel tubes:

This delivery condition also involves cold working, but the resulting tube has a lower level of hardness compared to BK. It is typically used when a combination of strength and ductility is needed.

3. Cold finished/stress-relieved annealing (BKS) hydraulic steel tubes:

In this condition, the steel tube undergoes cold working followed by a stress-relieving annealing process. The purpose of annealing is to eliminate internal stresses and improve the tubes dimensional stability.

4. Annealed (GBK) hydraulic steel tubes:

The steel tube is fully annealed in this delivery condition. Annealing involves heating the tube to a specific temperature and then slowly cooling it to relieve stresses, increase ductility, and improve machinability.

5. Normalized (NBK) hydraulic steel tubes:

The tube is subjected to a normalizing process in this delivery condition. Normalizing involves heating the tube to a temperature above its critical point, followed by air cooling. This process enhances the tubes mechanical properties and removes any irregularities in the microstructure.

These different delivery conditions allow manufacturers to provide hydraulic steel tubes with varying levels of hardness, strength, ductility, and dimensional stability, based on the specific requirements of different applications.

Hydraulic steel tubes