Enterprise Solutions
Stainless Steel Pipe and Water Tank Welding
I. Construction Preparation
1. The welded stainless steel water tank is fabricated using high-quality SUS304 or 316L stainless steel plates and glass-fiber-reinforced plastic panels. Materials are cut according to the tank’s specifications, then undergo a series of processes including shearing, film application, pressing, shaping, alignment, and final inspection before being delivered as qualified products.
2. Prior to construction, it is essential to thoroughly study the construction drawings and relevant technical documentation. Water tank construction drawings must be cross-checked with structural and architectural drawings, the tank’s manufacturing process should be fully understood, and all applicable construction and acceptance standards must be reviewed and documented in a detailed construction plan.
3. Before starting work, ensure that power supply at the construction site is properly arranged. Electrical usage on-site should be coordinated with the contractor but must meet operational requirements.
4. The construction area must be kept orderly, with a dry and well-ventilated working environment.
5. The strip foundation for the water tank must comply with the design drawings and installation requirements, with a minimum height of 200 mm and an allowable deviation of no more than 5 mm across all foundations.
6. A dedicated site supervisor shall be assigned to oversee all aspects of the construction team’s activities and to conduct continuous quality control of the water tank throughout the entire project.
Materials Preparation
1. Raw materials such as welding wire and electrodes must undergo rigorous quality inspections; their chemical composition, mechanical properties, and weldability must conform to national standards.
2. Stainless steel pressed plates must be carefully inspected upon arrival and prior to use to ensure they meet all relevant quality and technical requirements.
3. Channel steel base frames must also be thoroughly inspected upon arrival and prior to use to confirm compliance with applicable quality standards.
4. Stainless steel tension rods and vertical posts must be inspected upon arrival and prior to use to verify that they meet all relevant quality requirements.
II. Major Equipment Preparation
1. Equipment: TIG welders, electric arc welders, angle grinders, argon cylinders, power distribution boxes, etc.
2. Tools: Adjustable wrenches, hand hammers, screwdrivers, pliers, cutting tools, welding tools, etc.
3. Measuring instruments: Spirit levels, steel tape measures, plumb bobs, calipers, protractors, string lines, etc.
III. Installation Process Flow
Pre-Welding Preparations
(1) Production Drawings and Process Procedures
Before welding begins, it is imperative to thoroughly familiarize oneself with the production drawings and process procedures for the welded structure. This step is crucial for ensuring smooth production of the welded product. Key aspects include:
The structural configuration of the product, the types of materials used, and associated technical requirements;
Dimensions of the welded areas, as well as the design of the weld joints and groove preparations;
The specific welding methods employed, along with parameters such as welding current, voltage, speed, and sequence, plus control of preheating and interpass temperatures during the welding process;
Post-weld heat treatment procedures, inspection methods for welded components, and quality requirements for the finished product.
(2) Base Material Pre-treatment and Cutting
1) Base Material Pre-treatment
Pre-treatment of metallic structural materials primarily involves straightening and surface treatment of steel prior to use. If steel is not handled in strict accordance with relevant operating procedures during lifting, transportation, and storage, various deformations may occur, such as overall bending, local buckling, or wave-like distortion, which render the material unsuitable for direct use in production and necessitate correction.
Thin plate straightening is typically performed using multi-roll leveling machines, while coiled steel sheets can also be leveled using similar equipment.
2) Cutting
Mechanical thermal cutting methods must be used for cutting, with each piece clearly labeled with product name, drawing number, specification, graphical symbols, and hole diameters. Only after passing inspection may the material be used. Manual scribing and template dimensions must adhere to standard tolerances, taking into account both welding shrinkage and machining allowances.
When cutting and preparing stainless steel plates, special attention should be paid to hardening phenomena near the cut edges.
3) Groove Preparation
To ensure that the weld bead thickness meets specified dimensions, avoids defects, and achieves full penetration, the edges of the weld joint must be prepared into various groove configurations based on plate thickness and welding process requirements.
On-site Welding Procedures
(1) Welding Sequence
1) Welding the Base Frame
Based on the dimensions of the water tank modules, determine the spacing of the channel steel. First, tack weld the channel steel in place, then use a spirit level to check for flatness before proceeding with full welding.
2) Fixing the Bottom Plate
Place the inspected and qualified water tank bottom plate onto the channel steel base frame (prior to placement, apply anti-rust paint to the channel steel to prevent corrosion between dissimilar metals).
Note: Applying anti-rust paint to the surface of the channel steel serves to prevent metal rusting and enhance coating adhesion. After painting, the metal is effectively isolated from air contact, and the anti-rust paint induces metal passivation, inhibiting chemical or electrochemical reactions between other substances and the metal, thereby providing effective rust protection. Furthermore, since the anti-rust paint reacts with the metal surface to form a passivation layer, the bond between the paint and metal becomes not only physical but also chemically strong, resulting in exceptionally high adhesion. This effectively isolates the channel steel from direct contact with the stainless steel panel, ensuring that the water quality inside the tank meets standards.
3) Fixing the Side Panels
Tack weld the inspected and qualified water tank pressed panels onto the bottom plate in sequence. After each panel is secured, use a spirit level and plumb bob to verify verticality; only when everything is confirmed correct should the next panel be tack welded, continuing until all side panels have been tack welded.
4) Fixing the Cover Plate
Secure the inspected and qualified water tank cover plate onto the side panels, with vertical posts installed between the center of the cover plate and the tank bottom to ensure overall flatness.
5) Installing Accessories
Fix the internal tension rods according to the tank’s structure and install both internal and external ladders.
6) Drilling Holes
Drill holes at the positions indicated on the drawings and according to the required pipe diameters, then tack weld short flange pipes at each opening. The flanges must be aligned horizontally and vertically as specified.
7) Perform overall welding of the water tank, ensuring that the welds are free of porosity, slag inclusion, and other defects.
(2) Welding Process
1) Welders must pass the appropriate qualification tests as stipulated by the “Welding Code” before being authorized to perform on-site welding.
2) It is strictly forbidden to arbitrarily strike an arc on the surface of the workpiece, test current, or use temporary welding supports.
3) The TIG torch and argon pressure regulator used by welders must be regularly inspected to ensure that the argon flow remains laminar during the TIG root pass.
4) Prior to joining, the groove surfaces and both inner and outer walls of the base material must be thoroughly cleaned of oil, paint, scale, and other contaminants until a metallic sheen is revealed. The cleaning range should extend 10–15 mm on each side, with a joint gap of 2.5–3.5 mm.
5) Joint gaps must be uniform and straight; forced fitting is prohibited, and misalignment should not exceed 10% of the wall thickness or 1 mm.
6) If local gaps at the joint are excessively large, they must be corrected; inserting any filler material into the gap is strictly forbidden.
7) Once the joint passes inspection, mark 4–5 points along the joint length for tack welding, using the same materials as for the final weld, with a tack weld length of 10–15 mm and a thickness of 3–4 mm.
8) After completing the root pass, carefully inspect the quality of the root weld and proceed with the TIG cap pass only if it is deemed satisfactory.
9) Arc initiation and termination must both occur within the joint; termination should completely fill the molten pool, guiding the arc back into the groove to extinguish it.
10) If defects arise during tack welding, TIG welding, or the cap pass, they must be ground away using abrasive tools before resuming welding; repeated melting to eliminate defects is strictly prohibited.
11) Pay close attention to the quality of the joint and the termination; ensure good fusion at the joint and complete filling of the molten pool during termination to guarantee weld tightness.
12) Immediately after completing the cap pass, clean up slag and spatter from the weld surface.
Causes of Defects in TIG Welding and Preventive Measures
Weld Defects
Causes
Preventive Measures
Porosity
Impure argon, ruptured gas hoses, moisture in the gas line, tungsten electrode contamination, or excessive metal fumes entering the molten pool.
Replace with pure argon, inspect the gas line, grind or replace the tungsten electrode, and thoroughly clean the weld.
Poor penetration with weld bumps
Uneven welding speed, lack of skill.
Strengthen basic training and maintain consistent welding speed.
Severe blackening and oxidation of the weld
Low argon flow, slow welding speed, high temperature, or excessive current.
Increase argon flow, speed up welding, or appropriately reduce current.
Shrinkage cavities
Improper termination method, abrupt stoppage of the arc.
Change the termination method and gradually slow down the welding speed to achieve a smooth finish.
Cracks
High or low welding temperature, poor penetration, or overheating.
Ensure full penetration, adjust current and welding speed appropriately, and change the termination position.
Incomplete penetration
Fast welding speed, low current.
Slow down the welding speed or increase the current.
Poor fusion
Misalignment, incorrect torch angle, or fast welding speed with low current.
Correct misalignment errors, master proper torch angles, and appropriately slow down the welding speed while increasing the current.
Burn-through
Inexperienced technique, excessive current or slow welding speed.
Reduce current or speed up welding, and strengthen basic training.
Surface damage to the weld
Inaccurate arc initiation, poor ground connection.
Initiate the arc accurately, avoid striking the arc directly on the workpiece, and ensure proper grounding.
Weld inclusion of tungsten
Striking the arc with the tungsten electrode in direct contact with the workpiece.
Maintain a certain distance between the tungsten electrode and the workpiece during arc initiation.
Irregular weld bead formation
Uneven gun travel speed, uneven wire feed speed.
Ensure consistent welding speed and wire feed, and strengthen basic training.
Undercut
Incorrect torch angle, uneven molten pool temperature, improper wire feeding.
Adjust the torch angle to achieve uniform molten pool temperature, and pay careful attention to the position, timing, and speed of wire feeding.
Water Pressure Test for Sealing Performance
After completing the welding, wipe all welded areas dry with a dry towel, then fill the tank to the marked capacity and let it sit for 24 hours. Afterward, wipe all welded areas again with a dry towel—there should be no trace of moisture on the towel.Water Tank Cleaning and Disinfection
Prior to being put into service, potable water tanks must be thoroughly cleaned. During cleaning, workers must wear plastic shoe covers before entering the tank. First, use a cleaning agent to scrub away dirt and grime inside the tank, then flush the interior with tap water until the effluent is free of particulates and appears clear and transparent—only then is the tank considered compliant.
Separation of Clear and Turbid Streams
The turbidity–clarification separator features an internal structure comprising a backwash water distributor, filter cotton balls, a stainless steel mesh, a flared inlet, baffles, and other components. A flocculant dosing unit delivers the flocculant and water through a pipeline mixer to the lower section of the separator, ensuring thorough mixing and reaction between the flocculant and water. This process causes fine suspended particles to aggregate into larger flocs. The flocculated water then passes through an intermediate baffle and is further filtered by high-efficiency filter cotton at the upper section, after which the clarified water enters the disc-membrane purifier. Meanwhile, the larger floc particles that have settled at the bottom are periodically removed via an automatic sludge-discharge system, effectively eliminating the aggregated contaminants. The first two stages address sand removal and turbidity reduction, ensuring that the effluent turbidity remains within the specified limits. The system also enables automated sludge discharge, continuous turbidity removal, and vigorous air–water backwashing of the filter cotton balls, thereby maintaining the upstream purification performance.
Automatic Sand and Dirt Remover
Automatically filters floating debris and settles sediment.
The automated control system performs automatic desilting.
Automatic cleaning during desilting.
Fully sealed design to maintain pipeline network pressure.
Purely physical filtration—no chemicals used.
All components are made of SUS304 stainless steel, ensuring no impact on water quality.
Iron and Manganese Removal Process
Oxidation is employed to convert low-valence iron and manganese ions in water into their high-valence forms, followed by adsorption and filtration to remove these oxidized species, thereby reducing the iron and manganese concentrations in the water.
Digital Integrated Variable-Frequency Controller for Water Supply
In the era of fully variable-frequency digital water supply, operational energy consumption is reduced, equipment safety is enhanced, the electrical control system boasts a high protection rating and a high degree of intelligence, and an Internet-plus smart water-supply platform is in place.
Digital Integrated Variable-Frequency Controller for Water Supply
Swimming Pool Water Treatment System
The swimming pool water treatment system operates on the principle of dynamic equilibrium, achieving thorough water purification through a continuous recirculation process. Pool water is collected via the overflow weir and routed to the balancing tank, where it mixes with make-up water before entering the recirculation piping. Driven by the circulation pump, the water first passes through a hair collector to remove hair and larger particulate debris; it then flows into an automatic coagulant dosing system. This system uses a precision metering pump to accurately dose aluminum sulfate solution (10% Al₂(SO₄)₃) into the recirculating water, promoting the aggregation of colloidal micro-particles into larger floc-like aggregates, which are subsequently removed by a quartz sand filter. The automatic pH adjustment system compares the signal from the pH sensor with the setpoint; a microcomputer performs a PLD calculation on the deviation and issues a control command, triggering a precision metering pump to inject dilute hydrochloric acid (10% HCl) into the recirculating water, thereby maintaining the pool water’s pH within the nationally prescribed range (pH 7.0–7.8) as specified in the “Swimming Pool Water Quality Standard” (CJ244-2007). Finally, the automatic disinfectant adjustment system uses either a residual chlorine sensor or a redox potential sensor to monitor the pool’s disinfection and sterilization efficacy. The controller then precisely doses sodium hypochlorite disinfectant (5% NaClO) via a metering pump, keeping the residual chlorine concentration within the national limit (0.3–0.6 ppm), effectively eliminating various bacteria and completing the purification and disinfection processes. System Performance Advantages: 100% labor savings, 100% chemical savings, 50–80% savings in thermal energy, 50–80% savings in makeup water, 50–80% savings in electricity consumption; the use of a new UPVC food-grade material that is corrosion-resistant and aging-resistant ensures no rusty water, while providing a clean, aesthetically pleasing appearance with a service life of over 30 years. System Equipment Composition: The system comprises a filtration unit, coagulant dosing equipment, disinfectant dosing equipment, electric valves, and an automated control system.
The YJDS brush-type self-cleaning filter (also known as the intelligent automatic filter) is suitable for a wide range of water supply systems, particularly those that require continuous operation without downtime. This filter effectively removes various mechanical impurities from the water system, ensuring the safe and reliable operation of system equipment. It automatically monitors the filter’s operating status by measuring the pressure differential between the inlet and outlet, thereby achieving true automatic detection, automatic cleaning, and automatic sludge discharge.
Air dissolved in water can have numerous adverse effects on heating and cooling water circulation systems. Accumulated gas creates air locks, leading to uneven system resistance, impaired circulation, and the generation of noise and cavitation. These issues reduce the pump’s effective head and operating efficiency, shorten the service life of equipment and piping networks, and decrease heat-transfer performance due to bubble formation on heat-exchanger surfaces. Air locks also make system commissioning more difficult and necessitate frequent manual air venting during operation. Moreover, dissolved oxygen in the system can cause oxidative corrosion, which further reduces system lifespan and directly compromises overall system safety.
1. In China, rainfall is abundant in the southeast and scarce in the northwest, with uneven spatial and seasonal distribution.
2. Per capita available freshwater resources are low, amounting to only one-quarter of the global per capita average.
3. Wastewater treatment is very costly;
4. The imbalance between water supply and demand has become a major constraint on China’s future development, and water scarcity is an undeniable reality. (We should not wait until the Arctic Ocean no longer has ice before we start addressing water conservation.)
2. Per capita available freshwater resources are low, amounting to only one-quarter of the global per capita average.
3. Wastewater treatment is very costly;
4. The imbalance between water supply and demand has become a major constraint on China’s future development, and water scarcity is an undeniable reality. (We should not wait until the Arctic Ocean no longer has ice before we start addressing water conservation.)
Microcrystalline Side-Flow Water Processor
The recirculating water bypass flow processor employs the principle of a superimposed-pulse low-voltage electric field, automatically adjusts the treatment signal based on water quality, and requires only bypass-flow treatment. This processor was developed on the basis of the original full-flow water processor.
When raw water containing hardness ions passes through the resin bed in a water softener, the calcium (Ca²⁺) and magnesium (Mg²⁺) ions in the water are exchanged and adsorbed by the resin, while an equivalent amount of sodium (Na⁺) ions is released. The water that flows out of the softener is thus softened water, free of hardness ions.
Air-source heat pump central heating system
It can be used for domestic hot water in hotels, inns, schools, hospitals, industrial and mining facilities, saunas, beauty salons, swimming pools, greenhouses, residential communities, villas, and other applications. It can be operated as a standalone system or integrated into a centralized heating network, with various product series and installation designs available to meet different heat supply requirements.
This project is located in the Baodi District Economic and Technological Development Zone and involves a ground-source heat pump central air-conditioning system for the duty and comprehensive building and the testing and monitoring building of the pilot-scale workshop at the Baodi Baoding Environmental Technology R&D Base.
The total cooling load for this project is 1,155 kW, the total heating load is 930 kW, and the total chilled/heated area is approximately 13,000 m². A ground-source heat pump system is employed, providing cooling in summer and heating in winter.
The total cooling load for this project is 1,155 kW, the total heating load is 930 kW, and the total chilled/heated area is approximately 13,000 m². A ground-source heat pump system is employed, providing cooling in summer and heating in winter.
How to Order Products & Services
Exquisite craftsmanship · Good quality
Exquisite Craftsmanship · Consistently High Quality
Meticulous craftsmanship and a relentless pursuit of excellence. We operate a fully integrated, end-to-end production line—spanning raw-material procurement, printing and manufacturing, post-press processing, and transportation and delivery—with rigorous control over every stage and detail to ensure superior product quality.
All rights reserved: Beijing Huaxia Yuanjie Water Technology Co., Ltd. Powered by：CEglobal View Business License
Online channels