Material:ZG25CrNiMo
Steel Grade | Chemical Composition % | |||||||
C | Si | Mn | Cr | Ni | Mo | S | P | |
ZG25CrNiMo | 0.25-0.30 | 0.20-0.40 | 0.70-0.90 | 0.40-0.70 | 0.40-0.70 | 0.15-0.25 | <=0.025 | <=0.025 |
ZG30CrMo | 0.26-0.33 | 0.17-0.37 | 0.40-0.70 | 0.80-1.10 | - | 0.15-0.25 | <=0.025 | <=0.025 |
ZG35CrMo | 0.32-0.40 | 0.17-0.37 | 0.40-0.70 | 0.80-1.10 | - | 0.15-0.25 | <=0.025 | <=0.025 |
Standard | Yield Strength Rp0.2 /MPa | Tensile Strength Rb / MPa | Elogation A / % | Reduction of Area Z/ % |
60K | ≥414 | ≥586 | ≥18 | ≥35 |
75K | ≥517 | ≥655 | ≥18 | ≥35 |
80K | 585-660 | ≥725 | ≥18 | ≥35 |
It is up to customers' requirement.
Item | Standard |
Casting Material | EN 10293/EN 10025/BS 3100/DIN 1681/DIN17205 |
Casting Tolerance in Blank | ISO 8062 CT 13 |
Size Tolerance | DIN ISO 2768m |
NDT | ASTM A609 Level 2 or 3 /EN 12680/ASTM E94 Level 2 or 3 |
Heat Treatment | Normalizing+Tempering+Quenching |
Hardness | As Required |
Most of castings for petroleum was made in rough machining.
We also have API certificate.
The material for BOP castings is ZG25CrNiMo.
To get more value for impact,we will always to quenching for it.
1)pattern making.
We have our own pattern workshop.
It can help us to control the pattern making process or save production cost.
Our engineer will check the pattern dimension and make a record.
Normally we will only help our customers to save the wooden pattern one year.
Most of the time we make wooden pattern.
2)Sand mold making
We have around 5-7 teams to make the sand mold.
Around 15% of our annual output is for petroleum machinery.
Some team is fixed for the petroleum machinery.
For the important corner,we use chorme ore sand,
while for other position,we use recycled silica sand.
On the inner surface of the sand mold,
we will make a painting and burn it for smooth.
3)Melting and pouring
We will do the melting in night for cheaper electricity charge.
And we will do the pouring in the early morning.
We will take the test sample before and after pouring for chemical composition.
4)Cooling
After pouring,the castings will be waiting for cooling.
The cooling time is up to the weight of the castings.
It will be 3 to 7 days or more time.
5)Heat treatment
Most time we will cut the riser before we do heat treatment.
We have around 10 furnaces for heat treatment.
Heat treatment of normalizing and tempering will cost 7 days.
6)Rough machining
The test block will be together with the castings for heat treatment.
Firstly if the chemical composition can meet the requirement,
we will do the mechancial property test.
Our labratory has gotten approval from CNAS.
After VT,we will check the machining allowance and draw the white line on the body of castings.
There will be 5-7mm margin left after rough machining.
After UT and MT,we will do the welding repair.
For the welding repair,we will have WPS for ZG25CrNiMo.
When the welding repair is finished,we will do the tempring for stress relife.
7)Quenching
For the quenching,we will send them to our sub-contractor.
Most of our petroleum machinery castings are for Shanghai Shenkai Group or manufacturer for BOP in Yanchen City.
Haian Haitai Casting Co.,Ltd. is established in 2003 in Huangqiao Town.
With a quick development,we are now can producing 3 to 190 tons piece.
The bigger the better for us.
Most of our castings are for cement mill.
No. | Equipment Name | Quantity(Set) |
1 | Sand analysis equipment | 1 |
2 | Impact sample low temperature meter | 1 |
3 | Direct reading spectrometer(OXFORD) | 2 |
4 | ONH analyzer | 1 |
5 | ZEISS metallurgical microscope | 1 |
6 | Pendulum impact tester | 1 |
7 | Microcomputer controlled electro-hydraulic servo universal test machine | 5 |
8 | Various hardness tester | 4 |
9 | Magnetic defect detector | 5 |
10 | Ultrasonic flaw detector(digital) | 1 |
11 | CX-52 Total station | 1 |
12 | Stylus roughness meter | 1 |
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.