AWS D8.8M pdf free download
AWS D8.8M pdf free download.Automotive Weld Quality- -Arc Welding of Steel.
4. General Provisions
4.1 Application
4.1.1 This specification provides the minimum quality requirements for arc welding of various types of automotive and light truck components.
4.1.2 The postweld acceptance requirements con- tamed in this document are mandatory when this spedflcation is referenced Ofl a product drawing. or in a contract. A product that does not conform to the acceptance criteria contained in this specification shall be reworked, scrapped, or accepted by concession.
4.1.3 Products that are shipped and do not conform may be rejected by the customer, reworked by the customer, or scrapped. all at the producer’s expense.
4.1.4 Any requirements deviating from the limits of this specification shall be designated on the engineering drawings.
4.1.5 Should any conflict occur between limits specified herein and those specified on the engineering drawings. the latter have precedence.
4.2 Welding Processes. This specification covers quality requirements for welds made by the shielded metal arc welding (SMAW), gas metal arc welding (GMAW), metal cored arc welding (MCAW),2 flux cored arc welding (FCAW), plasma arc welding (PAW), gas tungsten arc welding (GTAW), and hybrid arc welding processes.
4.2.1 Welding Procedures. Welding procedures list those variables (and their limits) that influence the quality of the weld. The welding process and weld procedures shall he developed and documented to demonstrate the capability to reliably produce welds on production parts over a specified range of variables. Information pertaining to welding procedure qualification can be found in various AWS and Original Equipment Manufacturer (OEM) standards.
4.2.2 Filler Metals. Filler metals shall conform to the requirements of the appropriate AWS filler metal specification. Filler metals used to weld zinc coated steel shall he evaluated for their ability to tolerate the zinc coating.
4.3 Limitations
4.3.1 Material Limitations. This specification covers the arc and hybrid arc welding of coated and uncoated steels including low carbon steels, stainless steel, high strength low alloy (HSLA) steels, and dual phase (DP) steels with relatively low carbon equivalent (CE) values generally not requiring any preheat or post heat treatment.
4.3.2 Surface Condition of Steel
4.3.2.1 The surface of the steel part in the weld area, at the time of welding, should he free from scale, rust. paint, lubricants, and other contaminants that could adversely affect the weld quality.
4.3.2.2 Lubricants for high pressure hydroforming applications tend to be more difficult to remove. Consult with the lubricant supplier for the recommended lubricant removal process.
4.3.3 Joint Fit
4.3.3.1 To ensure proper joint fit, all parts shall he located for maximum weld effectiveness. i.e., minimum gap and repeatable location.
4.3.3.2 To ensure consistent weld quality in fillet welds, the joint gap should not exceed O.3T1 where T1 is the thickness of the thinnest part. Additionally, the gap should not exceed the diameter of the filler wire. This should be true for all thicknesses in the range from 2 mm to 5 mm for single arc processes. For tandem arc welding, the range from 2 mm to 5 mm material thickness would allow a maximum gap of 2.0 mm. Note that this size gap only applies for welding done in the flat or horizontal positions. For lap penetration joints with high power density processes such as hybrid laser, the joint gap should not exceed 0.2 mm. The specific range of gap values listed above is dependent on the welding process and joint configuration. Larger gaps than specified can adversely affect structural performance or fatigue life.AWS D8.8M pdf download.
