Manufacturing process of stainless steel shell and tube condenser

Stainless steel shell and tube condenser is an important heat exchange equipment, widely used in chemical, petroleum, refrigeration and other industries. It exchanges heat between the cooling medium in the stainless steel pipe and the steam outside the pipe, so that the steam condenses into liquid, thereby realizing the transfer and utilization of heat. This article will introduce the manufacturing process of stainless steel shell and tube condenser in detail.

1. Preliminary preparation

Determine the design parameters

Equipment specifications: Determine the nominal diameter, heat exchange area, design pressure, design temperature and other key parameters of the condenser.

Material selection: According to the working environment and medium characteristics, select suitable materials, such as S30408 ​​stainless steel for shell and heat exchange tubes, Q245R and 16Mn for tube boxes.

Develop a manufacturing process plan

Based on the structural characteristics of the equipment, analyze the important links that affect the manufacturing quality of the equipment, and develop a manufacturing process and quality control plan.
2. Shell manufacturing

Cutting and planing

Strictly control the cutting size of each section of the cylinder, and determine the cutting and planing size according to the principle of an allowable upper deviation of 10mm for the circumference to ensure that the diagonal error does not exceed 2mm.

Welding

The longitudinal and circumferential welds are welded by GTAW base, SMAW intermediate layer, and SAW cover to reduce welding deformation and improve work efficiency.
When the longitudinal and circumferential welds are assembled, the misalignment of the joints is guaranteed to be no more than 0.5mm.

Shell quality control

The shell manufacturing tolerance (diameter tolerance, roundness, straightness) and the diameter tolerance of the baffle determine whether the tube bundle can be smoothly loaded and the performance of the equipment can be guaranteed.
By measuring along the four directions of 0°, 90°, 180°, and 270° along the circumference, ensure that the maximum straightness of the shell does not exceed 3mm.
3. Tube sheet and baffle processing

Tube sheet processing

Use CNC drilling machine to drill holes, strictly control the diameter, verticality and spacing of the tube holes.
The direction of the tube hole is consistent with the direction of the tube penetration, which is convenient for tube penetration.

Baffle processing

According to the requirements of the drawing, the outer diameter of the baffle needs to be accurately processed to ensure that the tube bundle can be smoothly loaded and meet the requirements of the drawing.
The baffle tube holes need to be drilled in batches, and the sequence number and the front and back marks should be made on each piece.
4. Assembly of tube bundle and shell

Tube bundle assembly

Due to the large number and heavy weight of heat exchange tubes, the fixed side tube sheet, tie rod, distance tube and baffle are fixed first, and some heat exchange tubes are inserted in a plum blossom shape.
Adjust the concentricity of the baffle and the tube sheet, and ensure that the entire tube bundle has sufficient rigidity, then install the tube bundle into the shell, and then insert the remaining heat exchange tubes.

Welding

Use asymmetric K-shaped groove welding joints, and install the support round tooling on the inside of the cylinder before welding to prevent the cylinder from deforming.
First weld the inner weld of the joint, and pass the PT test, and then weld the outer weld of the pipe.
5. Inspection and testing

Measurement of shape and position dimensions

Measure the maximum and minimum diameter difference of each section of the shell, the parallelism of the two end faces, the outer circumference of each section of the cylinder, etc., to ensure compliance with the GB151-1999 standard.

Welding quality inspection

Perform visual inspection and non-destructive testing on all welded joints to ensure that the welding quality meets the design requirements.
VI. Final inspection and quality control

Overall inspection

Perform an overall inspection of the entire equipment, including visual inspection, dimensional measurement, pressure test, etc., to ensure that the equipment meets the design requirements.

Quality control

During the manufacturing process, strengthen process control and inspection and testing to ensure the final product quality of the entire equipment.
VII. Maintenance and care
Regularly maintain and care the stainless steel shell and tube condenser to ensure the normal operation of the equipment and extend its service life.

Through the above detailed production process, the manufacturing process of the stainless steel shell and tube condenser is clearly presented. Each step strictly follows the design requirements and technical standards to ensure the reliability and durability of the equipment.