Hydraulic warping head is used for the hydraulic capstan in tugboats. The material is mainly grey cast iron BS1452 GR220.
There are some iron foundries who have good experience to produce these capstan heads. Dandong Foundry has made many warping head for the clients overseas. Herein, I will talk about some quality issues about them.
Hydraulic warping heads are not difficult to manufacture since they have a suitable structure for casting process, however, as a buyer, you still need to notice some aspects as following:
1. Dynamic balance
Dynamic balancing is important for the warping heads although their rotation rate is not high. In order to keep the good dynamic balancing, you should require your suppliers to use the resin sand casting process to produce them. By this casting process, the dimensions and dynamic balance can be kept.
2. Material Physical Properties
Since the hydraulic warping head has to take heavy tensile, so their material should have good tensile strength and hardness. Otherwise, it will cause the potential danger in your application. Most of iron foundries in China have the capability to do the tensile strength and hardness test. So, these issues are not difficult for suppliers, but just need them to take them seriously.
Some clients may choose the ductile iron (SG) as the material considering the higher tensile strength and better physical properties. Such as ductile iron ASTM A536 60-40-18 or 65-45-12. This is correct choice. However, if grey iron can meet your tensile strength requirement, you do not need to choose the ductile iron since ductile iron is more costly.
3. Surface Quality
Since most of the surfaces are rough surfaces, so as a buyer, you should ask your suppliers to grind them carefully. Remove all the sharp edges and burrs, and grind them smoothly. Welding should be permitted, but the welding positions should not affect the use.
4. Coating and Painting
The suppliers should do the anti-rust primer painting before delivery. Normally, our clients will paint the finish painting by themselves, but we can do the finish painting if you need.
As I said, the hydraulic warping heads are not difficult to produce, just need the careful works of the manufacturers.
This article was from Dandong Foundry .
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