Gerund Pipe Industry

Product Description
Spiral steel pipe is a spiral seam steel pipe made of strip steel coil as raw material, extruded at room temperature, and welded by automatic double-wire double-sided submerged arc welding process
Welding Seam Processing
Spiral steel pipe The strip is fed into the welded pipe unit. After being rolled by multiple rollers, the strip is gradually rolled up to form a circular tube blank with an opening gap. Adjust the reduction amount of the extrusion roller to make the weld The gap should be controlled at ~ and both ends of the welding joint should be flush.
.If the gap is too large, the proximity effect will be reduced, the eddy current heat will be insufficient, and the inter-crystal bonding of the weld will be poor, resulting in lack of fusion or cracking. .If the gap is too small, the proximity effect will increase and the welding heat will be too high, causing the weld to burn or form a deep pit after extrusion and rolling, affecting the surface quality of the weld. .After the two edges of the tube blank are heated to the welding temperature, under the squeeze of the squeeze roller, common metal grains are formed to penetrate and crystallize with each other, and finally form a strong weld. If the extrusion force of the spiral steel pipe is too small, the number of common crystals formed will be small, the strength of the weld metal will decrease, and cracking will occur after stress. If the extrusion force is too large, the molten metal will be extruded out of the weld, not only The strength of the weld is reduced, a large number of internal and external burrs are produced, and even defects such as welding overlaps are caused.

br/>Main process features of spiral steel pipe
During the forming process, the steel plate deforms evenly, has small residual stress, and does not produce scratches on the surface. The processed spiral steel pipe has greater flexibility in the size range of diameter and wall thickness, especially in the production of high-grade thick-walled pipes, especially small and medium-diameter thick-walled pipes. It has advantages that other processes cannot match, and can satisfy users More requirements in terms of spiral steel pipe specifications.
Adopting the advanced double-sided submerged arc welding process, welding can be achieved at the best position, and defects such as misalignment, welding deflection, and incomplete welding are less likely to occur, and the welding quality is easy to control.
Conduct % quality inspection on steel pipes so that the entire process of steel pipe production is under effective detection and monitoring, effectively ensuring product quality.
All equipment in the entire production line has the function of networking with the computer data collection system to realize real-time transmission of data, and the central control room monitors the technical parameters in the production process.
Commonly used materials generally include,,,,,.
The standards used are generally divided into / (ministerial standard, also called spiral submerged arc welded steel pipe for ordinary fluid transportation pipelines), / (national standard, also called oil and gas industry transportation steel pipe delivery technical conditions, first part grade steel pipe (requirements) Strictly graded steel pipes), (American Petroleum Institute, also called pipeline steel pipes, which are divided into two levels), / (spiral seam submerged arc welded steel pipes for piles).


Production process
Spiral steel pipe is made of strip steel coil as raw material, extruded at normal temperature, and welded by automatic double-wire double-sided submerged arc welding process. Seam steel pipe
The raw materials are strip steel coil, welding wire and flux. They must undergo strict physical and chemical inspections before being put into use.
For the head-to-tail butt jointing of steel strips, single-wire or double-wire submerged arc welding is used. After being rolled into steel pipes, automatic submerged arc welding is used for repair welding.
Before forming, the strip steel undergoes leveling, trimming, planing, surface cleaning, transportation and pre-bending.
Electric contact pressure gauges are used to control the pressure of the cylinders on both sides of the conveyor, ensuring smooth conveying of the strip.
Adopt external control or internal control roller forming.
The weld gap control device is used to ensure that the weld gap meets the welding requirements. The pipe diameter, offset amount and weld gap are all strictly controlled.
Both internal and external welding use American Lincoln electric welding machines for single-wire or double-wire submerged arc welding to obtain stable welding specifications.
The completed welds have been inspected by an online continuous ultrasonic automatic flaw detector, ensuring 100% non-destructive testing coverage of spiral welds. If there is a defect, it will automatically alarm and spray mark, so that production workers can adjust the process parameters at any time to eliminate defects in time.
Use an air plasma cutting machine to cut the steel pipe into individual pieces.
() After cutting into individual steel pipes, the first three steel pipes in each batch must undergo a strict first inspection system to check the mechanical properties, chemical composition, fusion status of the welds, the surface quality of the steel pipes, and non-destructive testing to ensure Only after the pipe making process is qualified can it be officially put into production.
The areas with continuous sonic flaw detection marks on the welds will undergo manual ultrasonic and radiographic re-examination. If there are indeed defects, they will be repaired and then undergo non-destructive inspection again until it is confirmed that the defects have been eliminated.
The steel strip butt welds and the pipes where the T-shaped joints intersect with the spiral welds are all inspected by radiography or radiographs.
Each steel pipe has undergone hydrostatic pressure testing, and the pressure is radially sealed. The test pressure and time are strictly controlled by the steel pipe water pressure microcomputer detection device. Test parameters are automatically printed and recorded.
The pipe end is machined to accurately control the end face verticality, bevel angle and blunt edge.


Hunan Gerunde Pipe Industry Co., Ltd. is a large enterprise integrating professional double-sided submerged arc welding spiral steel pipes, anti-corrosion and insulated steel pipes, anti-corrosion steel pipes, epoxy coal pitch anti-corrosion steel pipes, cement Mortar anti-corrosion steel pipes, anti-corrosion steel pipe insulation pipe series include polyurethane foam insulation pipes, steel-sheathed steel insulation pipes, prefabricated direct-buried insulation pipes, steam direct-buried insulation pipes and other complete specifications. Our factory has a large number of stocks all year round. Welcome to call us for consultation< br/> Anti-corrosion steel pipes have advantages such as light weight, high strength, heat insulation, sound insulation, flame retardant, cold resistance, anti-corrosion, non-water absorption, and fast construction. Indispensable materials such as thermal insulation, anti-corrosion, waterproofing and sealing. Anti-corrosion steel pipes are used in anti-corrosion and cold insulation projects for various indoor and outdoor pipes, including heating pipes, local air-conditioning pipes, chemical industry, and other industrial pipes. Overview: Since the birth of synthetic materials in the 1930s, foamed anti-corrosion pipes have been rapidly developing as an excellent thermal insulation and anti-corrosion material. Used for various heating, refrigeration, oil transmission, steam transmission and other pipelines. It is widely used in various heating, refrigeration, oil transmission, steam transmission and other pipelines. The anti-corrosion of anti-corrosion steel pipes is divided into three layers from the inside to the outside.
The first layer of pipeline anti-corrosion work. The steel pipe layer generally uses seamless pipes (88), spiral welded pipes (8/8) and straight seam welded pipes (88) according to the plan and customer conditions. . After the surface of the steel pipe is processed by advanced rust removal technology, the rust removal grade of the steel pipe can reach the grade in the 88th standard, and the surface precision can reach 8.0 micron in the standard.
The first layer of pipeline anti-corrosion layer is made by injecting rigid foam plastic liquid into the cavity formed between the steel pipe and the outer sheath using a low-pressure foaming machine. It is commonly known as the tube-in-tube foaming process. Its functions are waterproof and anti-corrosion, and the third is to support the self-weight of the heating network. When the temperature of the conveying medium is ℃℃, rigid polyurealate foam plastic is used as the anti-corrosion layer. Special ordinary grade/reinforced grade seamless anti-corrosion steel pipes (anti-corrosion seamless steel pipes) for natural gas pipelines, ordinary grade/reinforced grade spiral anti-corrosion steel pipes (anti-corrosion spiral steel pipes), domestic professional natural gas anti-corrosion pipeline suppliers. Reinforced anti-corrosion seamless steel pipes, anti-corrosion steel pipes for underground water transmission, anti-corrosion steel pipes for gas transmission, anti-corrosion steel pipes for heating network heating, etc. are complete in specifications and are of high quality and low price. Welcome to visit and order


Anti-corrosion steel pipes for natural gas transportation, straight seam steel pipes and seamless steel pipes are used as base materials to produce anti-corrosion steel pipes. Anti-corrosion steel pipes
Three-layer polyethylene steel pipes for oil and natural gas. Anti-corrosion steel pipes. Implementation standards/
, Oil and gas use (single-layer sintered epoxy powder anti-corrosion), (double-layer sintered epoxy powder anti-corrosion) implementation standards/
, water supply pipeline cement mortar lined steel pipe anti-corrosion. Implementing standards
, water supply pipelines, and anti-corrosion in steel pipes with polymer non-toxic coatings.
, water supply pipelines, epoxy drinking water equipment, non-toxic coating steel pipe internal anti-corrosion.
, Epoxy coal pitch wrapped glass cloth steel pipe anti-corrosion. Implement standards/
and various types of heavy-duty anti-corrosion coatings for steel pipe anti-corrosion.
, Thermal pipeline steel pipe insulation and anti-corrosion steel pipe. (Polyurethane foam insulation layer) This product is widely used and is suitable for the anti-corrosion of steel structures and mechanical equipment, various storage tanks, transportation pipelines and other steel materials in marine facilities, petrochemical industry, construction industry and other industrial and mining enterprises.
Anti-corrosion steel pipe products include/reinforced anti-corrosion steel pipes, single-layer epoxy powder anti-corrosion steel pipes, epoxy coal pitch anti-corrosion steel pipes, drinking water pipe inner wall anti-corrosion steel pipes, steel pipes cement mortar lined anti-corrosion steel pipes, high-density polyethylene coated steel pipes .


Hunan Gerunde Pipe Industry Co., Ltd. produces and operates spiral steel pipes (spiral seam welded steel pipes, spiral welded pipes, Cangzhou spiral steel pipes, spiral pipes, spiral wound steel pipes), seamless steel pipes (without Seam pipes), straight seam steel pipes (straight seam welded pipes), hot rolled steel pipes, heat expanded steel pipes, welded steel pipes, galvanized steel pipes, galvanized pipes, flanges, elbows, large bends, tees, large and small heads and other pipe fittings. The company is based on quality and comprehensively implements quality management. Our company has been producing double-sided submerged arc welded spiral steel pipes of various specifications and special specifications for many years, according to petroleum industry standards. National standards, production, grade various types of steel pipes, widely used in petroleum. gas. Natural gas. Thermal power generation and other basic projects. At the same time, we operate seamless steel pipes. Straight seam steel pipe. Thermal expansion steel pipe. Seamless steel pipe. The inventory is large and all are traded in spot. We welcome new and old customers to visit or call our company to discuss cooperation! We will serve you wholeheartedly.


Hunan Gerunde Pipe Industry Co., Ltd., the company's main advantages are welded pipes, square pipes, seamless square pipes, thick-walled square pipes, large-diameter square pipes, galvanized square pipes, Hot-dip galvanized square tube, square tube, square tube, etc. We can process and cut various special-shaped parts according to your needs, and can also customize futures of various materials and specifications according to your requirements.
The company specializes in the production and sales of square tubes, seamless square tubes, thick-walled square tubes, large-diameter square tubes, galvanized square tubes, hot-dip galvanized square tubes, square tubes, square tubes, square tubes, square rectangular tubes, Rectangular tube etc. The main products are square tubes* and rectangular tubes*. The production scope includes various square tubes, rectangular tubes, square and rectangular tubes, galvanized square tubes, square tubes, low alloy square tubes, seamless square and rectangular tubes, large diameter square and rectangular tubes, thick-walled square and rectangular tubes, and high-frequency double welding Sewing square and rectangular pipes, welded pipes, square pipes, square pipes, galvanized square pipes, thick-walled square pipes, seamless pipes and various steel pipes, galvanizing processing, pipe forming processing, drawing and bending arc bending pipe processing with wall thickness range. Cold-formed steel units, roll bending and roll extrusion production lines, bending, straightening, cutting and polishing equipment, large-diameter, thick-walled square and rectangular tubes are our flagship products. Among them, the galvanized square and rectangular pipe production line has advanced online zinc replenishing technology to repair the zinc layer that has fallen off the weld position and protect the corrosion resistance of the weld. Product diameters include square tube** and rectangular tube*. It integrates longitudinal shearing and rolling, cold bending, welding and galvanizing. It uses high-quality hot and cold coiled plates, medium-thick steel plates and advanced equipment to produce high-frequency square tubes of various specifications and models, with an annual production capacity of 10,000 tons. Seamless square and rectangular pipes are a new product series developed by our company along the development track of deep processing of steel pipe products. They use seamless steel pipes or round pipes of welded steel pipes as the base material, and are pushed and rolled by cold rollers to form large-diameter thick-walled pipes. Square and rectangular special-shaped steel pipes. Therefore, it has the characteristics of high quality, multiple varieties and large wall thickness.