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PRODUCT SPECIFICATION
Pipe O.D: φ 406.4 – φ 1422.4mm Pipe Length: Max. 12.4m
Wall Thickness: When the steel grade is X70, the wall thickness ranges from 6.4 to 27mm. When the steel grade is lower, the wall thickness will be increased accordingly.
Product Standard: IS03183, API Spec 5L, GB9711 etc.
Capacity: The annual output is 0.2-0.3 million tons.

APPLICATION
The pipes are mainly used as long distance transportation pipeline for oil, gas, liquid coal etc. on land and off­shore, and also can be applied as construction pipes on offshore platform, power station, petrochemistry and city construction etc.

certification
LongForza received IS09001 quality system assurance certification on June 3, 2002. The pipe has obtained API monogram certificate on March 24, 2003. On August 29, 2003, we passed the environment protection acceptance inspection by National Environmental Protection Bureau. Our management philosophy is: customer’s satisfaction is our utmost objective.

Major Characteristics

1. The pipe internal stress is very small and uniformly distributed after the full-length expansion. The corrosion and cracking of the pipe owing to stress can be effectively prevented. The application of welding on site is very easy because of the high dimension precision;
2. The inside and outside welding are performed after tack welding, so the welding process is very stable with good weld quality;
3. The NDT is easy to perform on the weld during production and field operation as well;
4. The length of the weld is shorter than that of the non-longitudinal seam pipe, so the probability of defects occurrence is very low;
5. The coverage of the pipe specification is very wide. The pipe can be either in very large diameter with thick wall or in very small diameter with thick wall.

Quality Control During Production
During production, LongForza firmly sticks to the quality policy of “Full participation, technical innovation, continual improvement, and customer satisfaction”, and the quality objectives of “100% of qualified ratio of delivered products and over 95% of customer satisfaction”. All personnel and all processes throughout the pipe production line are under effective quality control through building of “Super Platform of Quality Management”. And the following “eleven-100%” is also achieved in quality inspection.

• 100% plate visual inspection
• 100% plate automatic ultrasonic inspection).
• 100% continuous ultrasonic testing of full weld before expansion 100% pipe-end weld ultrasonic inspection before expansion
• Full weld 100% X -ray inspection before expansion
• Full weld 100% industrial TV inspection before expansion 100% pipe hydrostatic test
• Full weld and pipe body 100% automatic ultrasonic testing after hydrostatic test Pipe-end weld 100% ultrasonic test after hydrostatic test
• Pipe-end weld 100% radiography or computer image handling after hydrostatic test
• 100% pipe visual inspection

Major Process Technical Characteristics

1. During the forming process, the deforn1ation of the plate is very uniform and the residual stress is very low and there is less scratch on the surface. The production range on the wall thickness and pipe diameter is very flexible. For the high strength material with small pipe diameter and heavy wall thickness this process has more advantages than other pipe production processes. More requirements on the product range from customers can be met.
2. The welding can be performed at an optimal position so the welding quality is easy to control because the inside welding and outside welding are performed after the tack welding. The welding defects such as offset, deflection and lack of penetration are very seldom to occur.
   
3. The full-length mechanical expansion of the pipe can effectively increase dimension precision and improve the internal stress distribution of the steel pipes, thus avoid damages due to stress corrosion. The expanded pipes are very convenient for site application.
4. The ll-item-l00% quality inspections have the complete pipe manufacturing process under effective check and control. And the product quality can be effectively guaranteed.
5. All the equipment of the production line has the function of automatic control. Production data gathering and real-time monitoring by computer can be realized on site.

Plate Edge Milling Machine: The machine can carry out automatic plate centering. And the cutter heads have float-copying function according to the waviness of the plate to ensure the two edges of the plate with the same groove dimensions. In addition, the milling speed and amount for each milling can be adjusted automatically according to steel grade, wall thickness and welding bevel angle. The good coordination between cutter heads and the plate clamping carriage feed system ensures constant parameters in the whole milling process, thus the quality requirements of the milling can be met. The precision of the welding chamfer is a major precondition for the quality of the later welding.
Pipe Forming Machine: It’s an intelligent hydraulic forming machine with CNC20 controller. During forming, the movements of upper & lower beams and plate delivery manipulator are controlled by computer. The stroke of the upper & lower beams and press force as well as the plate feed can be adjusted automatically according to steel grade, plate wall thickness and plate width. The upper & lower beams have the function of the deformation compensation to avoid the negative effect on the forming process due to the upper & lower beams deformation. The straightness in the full length of the plate can be ensured during the forming process. The forward length of each step is uniform so that the roundness and the welding edge parallelism can be ensured as well.
Tack Welding Machine: During tack welding, the open seam pipe is transported through stands designed as roller cage with nine rows of rollers. In this roller cage, the longitudinal edges of the open seam pipes are positioned exactly parallel to one another and welded, the exact guidance prevents effectively from the edge offset and creates a uniform welding gap. The tack welding is performed using high power and continuous gas metal arc welding (MAG welding) which is traced by laser system. The welding machine is imported from German U&S Company, which is very famous in this field. The continuous tack weld acts as a weld backing for the subsequent inside & outside welding.
Inside Welding & Outside Welding Equipment: All welding equipment is imported from German U&S Company. This company is a specialist manufacturer for LSAW pipe welding equipment with rich experience especially in the multi-electrode process. By using this welding machine, the quality of the welding can be ensured.
Mechanical Expander: The main purpose of an advanced mechanical expander is to size and straighten the pipe and increase the dimension precision of the pipe as well as improve the residual stress distribution status.