Galvanized mild steel welded seam welding proces

Date: 2019-10-18

Galvanized mild steel welded seam welding proces Steel surface coating is designed to corrosion or decorative, or both. The seam welding, not only to obtain a sufficient joint strength,but also required to maintain the function of the coating. By the strength requirements, seam welding process and uncoated steel is similar, taking into account the requirements of the coating, welding process parameters shall make the necessary adjustments, then pay attention to the impact of contact resistance coating, allowing the electrode indentation, coating and mother wood and metal alloys tendency to form adhesions occur with electrodes. Galvanized steel pipe is to increase the corrosion resistance of steel, but after galvanized mild steel is more difficult than not galvanized steel plate welding. Mainly due to the low melting point of the zinc coating (about 419C), during welding galvanized layer is first melted and the roller member and the welding electrode and the welding member and the contact surface of the welding current distribution member, the contact area increases, the current density decreases and the contact surface of the electrode and weldments galvanized layer melts, and the electrode face bonding, the copper electrode alloying (CuZn), its electrical conductivity, thermal performance deterioration. The boiling point of zinc 906C, when the temperature exceeds this temperature, the evaporation of zinc. The formation of pores or cracks in the nugget, the heat affected zone is diffused into the connector causes embrittlement cracks may be under pressure. Tests showed that the smaller the penetration rate (10 – 26%), fewer crack defects; welding speed is high, the cooling conditions are poor, hot surface and deep penetration, is easy to crack. Therefore, ensuring the nugget diameter and joint strength conditions, should try to use a small current, low welding speed and a strong external cooling. Electrodes should be used for embossing roller drum drive, in order to keep the tube round trim and clean the surface electrode size. Post time: Oct-18-2019

Prev : Exhaust pipe for auto
Next : ASTM A106 Carbon seamless steel pipe
Tags : dsaw steel pipe , steel tube manufacturer , coated steel pipe

News

Latest news list

How to Reduce Erosion and Wear in Steel Elbows

Steel Elbows redirect flow in industrial piping systems,but this change in direction can make them vulnerable to localized erosion,When fluids carry sand,scale,catalyst particles or other solids,repeated particle impacts may gradually reduce the Steel Elbow wall thickness,Corrosion can accelerate the damage when the fluid is also chemically aggressive,Reducing Steel Elbow erosion starts with identifying the wear mechanism,reviewing operating conditions and tracking wall-thickness changes,The right solution depends on the process,material,fitting geometry and piping design,
How Are Steel Reducers Manufactured and Quality Checked

A steel reducer connects pipes of different diameters while providing a controlled transition in a piping system,Its dimensions,material properties and wall-thickness distribution affect installation,flow conditions and service reliability,For project buyers,understanding steel reducer manufacturing and quality control helps ensure that the supplied fittings match the piping design and applicable specifications,
How to Prevent Leakage at Steel Pipe Fitting Connections

Leakage at steel pipe fitting connections can cause unplanned shutdowns,fluid loss,maintenance costs and safety risks,A steel tee,reducer or elbow may meet its dimensional requirements,yet the connection can still leak because of poor fit-up,joining defects,damaged sealing surfaces or excessive operating loads,Preventing leakage requires attention to the complete piping system,from component selection and installation to inspection and operation,The correct approach depends on whether the connection is welded,flanged or threaded,
How Are Steel Tees Manufactured and Inspected

Steel tees are butt-welding pipe fittings used to connect branch lines to a main pipeline,They are commonly specified in oil and gas,petrochemical,power generation and other industrial piping systems,Their suitability depends on more than nominal size: material grade,branch geometry,wall thickness,manufacturing quality and inspection requirements must all match the project specification,For engineers and purchasing teams,understanding how steel tees are manufactured and inspected helps identify the information that should be confirmed before an order is placed,
How to Store and Handle Oil Casing Before Installation

Oil casing needs proper protection from delivery through installation,Poor lifting practices,damaged thread protectors,unsuitable storage conditions or lost product identification can create problems before casing reaches the well,For drilling contractors,site managers and procurement teams,careful receiving,storage and handling help preserve product condition and prevent avoidable delays,