Shipbuilding Dockyard Marine Rudder Horn Casting

The rang of material for our class certificate is carbon or carbon manganese.

The heat treatment is normalizing and tempering.

We can't do quenching for marine castings(didn't get approval).

We started our business for marine castings since 2011.

We cooperate with most of domestic famous shipyards.

Stern boss is the most we had made for shipyards.

To guarantee the quality,we use refining furnace to improve the quality of melting steel.

1)The engineer will firstly prepare the technology and do a simulation before pouring.

2)We will make a pattern of the ruddern horn based on engineer's technology.

It will cost us around three weeks.

After that the engineer will check the dimension and make a record.

In fact,now we more supply stern boss,rudder carrier.Rudder horn is not too many to see.

3)Sand molding making will be made by experienced wokrers.

4)Pouring and cooling.

Cooling time is up to the castings' weight.

It is normally 72 hour,96 hours or 120hours.

There are one 8tons electrical arc furnace;

Two 50 tons medium frequency furnace;

One 120 tons refining furnace and one 120 tons VD furnace;

5)Clean the sand and cut the riser before heat treatment

6)Heat treatment will cost 7days( 4 days normalizing and 3 days tempring).

There are 8 heat treatment furances with max. one is 12m*9m*6m.

Also the largest size of the casting is 12m*9m*6m.

7)dimension check and draw a line for machining.

8)Rough machining

In 2021,we bought several new machines including a 10m vertical lathe.

9)NDT withe qualified inspector

10)Welding repair if needed and tempering for stress relief

11)Final machining and NDT.

Before we do the final machining,we firstly do rough machining and NDT.

To guarantee the quality,we add a procedure which is called "semi-finished machining" by us.

As we know even we do NDT,noboday can guarantee it is 100% no small defect to be found when we do final machining.

So we add "semi-finished machining" to avoid defects.

12)Customers' inspection and packing.

Normally the packing is naked packing because the castings for shipbuilding are always big.

Or if it is small ones,we can make wooden cases for them.

Haian Haitai Casting Co.,Ltd. is established in 2003. 

We supply large steel castings with low carbon or alloy steel from 3 tons to 150 tons per piece.

With a quick development,now we had supplied steel castings 6,000 tons per month.

There are three workshop for sand mold making,one workshop for machining and one for post procedure.

We have 9 class certificate:ABS,RINA,DNV,LR,KR,BV,CCS,NK and have cooperation with most of Chinese famous shipyards and some foreign shipyards.

Our factory is not the manufacturer of lowest price,but our quality is more reliable.

When we purchase something,price is very important,but a good quality can help you avoid problems.

We are near to Shanghai and China is famous for shipbuilding.

We pay more attention on marine castings since 2015.

After more and more customers know us,we get more and more orders from domestic market.

For marine castings,experience is very important.

We made marine castings for different types of vessel,such as container vessel,bulk ship and LNG ship.

We do the test according to diffrent production step,

such as chemical composition,UT,MT and mechanical property.

In 2021,Haitai inspection and testing center got approval from CNAS.

Our company is near to Shanghai port and we can supply different packing according to customers' specification.