Casing quenching tempering line process flow

Casing quenching tempering line process flow

Casing quenching tempering line is an important heat treatment process to improve the hardness of the oil casing. The following is the flow of the quenching and tempering process of the oil casing pipe.

The main technological process of induction heating equipment in oil pipe quenching and tempering production line is:

According to the production requirements, the operator can use crane to lift the steel pipe onto the storage platform, and then arranged pipes in order manually.When every procedure of the line is in good condition, start the frequency transportation roller table in normal rotation state. Manual or automatic start feeding machine to work. Under the control of sensor, the feeding device will lift the pipes on the alignment device and rolled to the roller table with slope angle. The frequency feeding transportation roller table will input pipes at set speed. The frequency feeding transportation roller table is single roller driving, and the speed and height can be adjusted. The roller type is V type. The transportation roller has slope angle, which can make sure the pipe rotate by itself during pipe transportation. This design is good for pipe uniform heating and avoid pipe bending after quenching. The transportation rollers between and before the induction heater is made of austenitic stainless steel. There is circulating water cooling system inside the feeding roller:this can not only cool the roller table but also keep the surface of roller table dry. The other transportation roller table are all made of wear-resistant stainless steel.

The steel pipe charge into induction heating zone for quenching, which consists of one set of 1600KW IF power supply(induction heating zone 1 for quenching), one set of 1250KW IF power supply (induction heating zone 2 for quenching), one set of 750KW(induction heating zone 3 for quenching) and multiple induction heating coil. The purpose of the double frequency heating is to make the heating temperature of the pipe end and pipe body uniform, and eliminate the non-uniform temperature distribution of the pipe end due to the edge effect. To ensure the heating temperature of the steel pipe is uniform, so that the internal structure of steel is heated to high temperature austenite. When the heated pipe enter into spray cooling zone, our system adopts outside spray cooling way to inject the water to pipe surface continuously. Outside spray is using the way of high pressure ring in the box for spraying to ensure hardenability. Considering the thick walled pipe hardenability, the user can add industrial salt or alkali in water, this method improves the cooling properties of quenching medium in high temperature area. 

The pipe after quenching will be sent to draining platform to remove the water left in the pipes.4 sets of pheumatic lifting machine will lift the pipes on the drainging platform. After 2-3 minutes empty water and water, and then 4 sets of pneumatic lift machine will place the pipes on the roller table for tempering. The tempering temperature will be 550-680 DEG C or higher temperature. Tempering induction heating system consists of 1 set of 1000KW IF power supply( induction heating zone 1 for tempering), 1 set of 700KW IF power supply( induction heating zone 2 for tempering), 1 set of 500KW IF power supply( induction heating zone 3 for tempering) and composed of multi induction heating coils. During tempering process, the carbide is fully and effectively precipitated, the retained austenite is eliminated, and the martensite structure is fully decomposed. The pipe structure after tempering is sorbite including equiaxed ferrite and fine cementite. The steel pipe after tempering will be sent to ERF furnace for holding (if required), then will be sent to cooling table for cooling gradually.In the end, the pipe will be sent to receiving platform.

Overseas manager: Tom Wang

Email:tom@foreverfurnace.com

Phone: 0086-13303078975(whatsapp, wechat,line)

Specialist of induction heating equipment and system in China; Glad to be your business partner in induction heating field.