For the moderate quality level D the excessive throat thickness is unlimited. It is not intended that they should be used as a mandatory, or contractual documents. If the document is revised or amended, you will be notified by email. All copyright requests should be addressed to. Acceptance The root concavity may be acceptable. Fillet welded joints This Section should be read in conjunction with Job Knowledge 66 Excessive convexity This feature is also covered by the definition for excess weld metal, see , and may be described as weld metal lying outside the plane joining the weld toes.
A 10mm leg length fillet with a root gap of 3mm gives an effective leg of 7mm a throat of 4. Please first with a verified email before subscribing to alerts. The information may be useful for a quality management system for the production of joints. The consequence of this imperfection is a significant increase in weld volume. Four classes are defined and they are equivalent to the defeat levels cfr. Additional guidance on fatigue loads is given. Furthermore, a smooth transition is required at the weld toes.
Its principles can also be applied to partial-penetration butt welds. Oversize fillet welds welds with a throat larger than required by the design As discussed in Job Knowledge 66, oversize fillet welds can represent a significant additional cost and loss of productivity. Codes of practice differ from standards in that they are intended to give recommendations and guidance, for example, on the validation of power sources for welding. They are designated by symbols B, C and D. Root concavity suck-back; underwashing A shallow groove that may occur in the root of a butt weld. Subscription pricing is determined by: the specific standard s or collections of standards, the number of locations accessing the standards, and the number of employees that need access.
The requirements for approvals are determined by the relevant application standard or as a condition of contract Table 1. This will depend on the relevant standard being worked to. The quality levels refer to production and good workmanship. Please first before subscribing to alerts. A detail or group of details will normally be ascribed one execution class.
Where possible mechanise the welding operation. Application standards and codes of practice ensure that a structure or component will have an acceptable level of quality and be fit for the intended purpose. Any use, including reproduction requires our written permission. Several types of loads are considered, e. Surprisingly, there is no reference to a 'smooth transition' being required at the weld toes for such weld shape. Acceptance The idealised design requirement of a 'mitre' fillet weld is often difficult to achieve, particularly with manual welding processes. That is if we can be sure there is good penetration the smaller fillet may be acceptable, however, this should be discussed with the designer of the fabrication.
The limits for this imperfection relate the height of the excess metal to the width of the bead with maximum values ranging from 3mm for a stringent quality level to 5mm for a moderate quality level. It has been updated so the web page no longer reflects exactly the printed version. However, 'if the joint separation is greater than 2mm the leg of the fillet weld shall be increased by the amount of the root opening, or the contractor shall demonstrate that the effective throat has been obtained'. The limits set by the standard. It is engineer responsibility to select the appropriate admissible level taking into account the importance of the welded piece and its destination.
However, it is used in the workplace to describe those welders whose skill and technical competence have been qualified to the requirements of an appropriate standard. Undersized fillet welds fillet welds smaller than those specified Common causes The welding related causes are associated with high welding speeds and low welding currents. It is also important to ensure that the parameters specified in the welding procedures specification are adhered to. Acceptance is related to the throat thickness. In effect the standards require that the minimum design throat thickness of the finished weldment is achieved. .
Quality Acceptance Levels for Welding Procedure and Welder Approval Tests When welding to application standards and codes, consideration must be given to the imperfection acceptance criteria which must be satisfied. If welder technique is the problem then retraining is required. Already Subscribed to this document. Some standards contain an appropriate section relating to the acceptance levels while others make use of a separate standard. A structure can include several execution classes. In the following some considerations about the welding prescriptions are reported as per Eurocode norm. Excess weld metal protruding through the root of a fusion butt weld made from one side only.
Common causes There are some welding related causes, eg high welding current, slow travel speeds, and some supervision related eg 'to be safe make this fillet bigger by x mm'. Use sufficient current and appropriate travel speed. Acceptance Therefore, it is normally assumed that fillet welds will be at least of the size specified. Avoidance Adhere to the specified welding procedure and parameters and do not add to the specified weld size. Fusion welding - Part 2: aluminium and aluminium alloys. Common causes Penetration becomes excessive when the joint gap is too large, the root faces are too small, the heat input to the joint is too high or a combination of these causes.
The quality levels which are the most appropriate for production joints will be determined by the relevant application standard which may cover design considerations, mode of stressing e. Common causes Poor technique and the deposition of large volumes of 'cold' weld metal. Common causes Poor workshop practice, poor dimensioning and tolerance dimensions on drawings. Their committees work with the manufacturing and service industries, government, businesses and consumers to facilitate the production of British, European and International standards. This standard also states that the size of the fillet weld can be increased to compensate for a large gap.