Abbreviations Used in Construction Industry - Part 4 (M to P)

Dear Readers, 

This continues from Part-3. For both seasoned professionals and newcomers, grasping construction management acronyms, construction estimating abbreviations, and construction project management acronyms is crucial for industry success.

Understanding a list of construction abbreviations is crucial. Recognizing these abbreviations is the initial step in learning to read construction blueprints.

221) M-Book – Measurement Book. It is used for work certification of executed quantity.

222) Mat’l – Material used for Construction.

223) Material Management (MM) – The Process of Managing and Coordinating the Delivery of Materials to a Construction Site.

224) M/c – Machine. Hand tool machines used for grinding, drilling, cutting operations.

225) MD – Man-Days is the cumulative product of no. of persons involved in work & no. of days they worked each. Generally, in construction involving labour, man days is very important feature to estimate amount work force needed and to quantify that.

226) MDL – Master Document / Drawing List. It is targeted at the following User Project Roles: Document Controllers (DC) with Owner's PM Team, Consultants, Contractors, and Specialist Contractors. Design Managers and their key review team members who will oversight design and shop drawings review & approval.

227) Mediation – A Form of Alternative Dispute Resolution Where a Neutral Third Party Facilitates Negotiations Between Disputing Parties.

228) MEP (Mechanical, Electrical, And Plumbing) – The Systems and Components of a Building That Provide Heating, Cooling, Electrical Power, and Plumbing.

229) MIG – Metal Inert Gas (MIG) welding is an arc welding process that uses a continuous solid wire electrode heated and fed into the weld pool from a welding gun.

230) MIS – Management Information System. It is a planned system of the collecting, processing, storing and disseminating data in the form of information needed to carry out the functions of management. The term usually refers to business operations not engineering.

231) MM – Man Month. It is similar to Man Day but calculated per month.

232) MOH – Materials on Hand. This refers to materials that have been purchased specifically for a project. In construction, this typically refers to materials that have been procured, but not yet installed. Physical Stock.

233) MoU – Memorandum of Understanding. It is a nonbinding agreement that states each party's intentions to take action, conduct a business transaction, or form a new partnership. This type of agreement may also be referred to as a letter of intent (LOI) or memorandum of agreement (MOA).

234) MP – Monthly Plan. It shows the monthly target and in line with the project schedule.

235) MPCS – Management Planning and Control System.

236) MPR – Monthly Progress Report.

237) MPT – Magnetic Particle Test.

238) MRC – Material Receipt Certificate.

239) MRM – Monthly Review Meeting.

240) MSDS (Material Safety Data Sheet) – A Document That Provides Information About the Hazards of a Chemical Substance.

241) MQP – Manufacturing Quality Plan. It is a basic test requirement during manufacturing process.

242) MTC / MTR – Material Test Certificate / Material Test Report.

243) MTO – Material Take-Off.

244) N/A – Not Applicable.

245) NCR – Non-Conformance Report / Non-Conformity Report.

246) NDA – Non-Disclosure Agreement.

247) NDCT – Natural Draft Cooling Tower.

248) NDT – Non-Destructive Test.

249) Negotiation – The Process of Discussing and Reaching a Mutually Agreed-Upon Resolution in a Construction Project.

250) NOC – No Objection Certificate.

251) N/S or F/S – Near Side or Far Side. It is used in structural fabrication drawing.

252) NTP – Notice to Proceed – This is a formal letter from an owner or director to a contractor or consultant to start work. It is usually the official start of contract time.

253) NTS – Not to Scale. “Not to scale" means the drawing is larger or smaller than real.

254) O2 – Oxygen gas.

255) O.C. – On Center – In dimensional callouts, on-center indicates the spacing between the center of an item or component and adjacent items or components, such as reinforcing steel, columns, footings, rails, etc. It’s the same as C.C. or “center-to-center.” It is distinct from “clear spacing.”

256) OH – Over Head. 

257) O&M – Operations & Maintenance.

258) OEM – Original Equipment Manufacturer. 

259) OPC – Ordinary Portland Cement.

260) OPEX – Operational Expenditure.

261) OSBL – Outside Battery Limit. It is the barricading of work limits.

262) OSHA (Occupational Safety and Health Administration) – A Federal Agency Responsible for Establishing and Enforcing Safety Standards in the Workplace.

263) OSL – Overhead Slab Level.

264) PAC – Plasma Arc Cutting. An arc cutting process using a constricted arc to remove the molten metal.

265) Paving – The Process of Laying Down a Surface for a Road, Parking Lot, Or Other Surface Area.

266) PAW – Plasma Arc Welding. An arc welding process that uses a constricted arc between a non-consumable electrode and the weld pool

267) PBG – Performance Bank Guarantee.

268) PCC – Portland Cement Concrete.

269) PD – Project Director, who holds end to end responsibility of that project.

270) P&ID – Piping and Instrumentation Diagram.

271) Plumbing Services – The Provision of Plumbing Services for A Construction Project.

272) P&M – Plant & Machinery. (Construction Equipment's)

273) PM – Project Manager, who manage the execution of Project.

274) PMG (Project Management Group) – The Planning, Execution, And Closing of Construction Projects Within Budget, Timeline, And Scope.

275) PMP (Project Management Professional) – A professional designation for project managers.

276) PO – Purchase Order. It is (PO) a legally binding document that confirms a business's intent to buy goods or services from a supplier.

277) P&OD – Personal and Organization Development. 

278) PPC – Portland Pozzolana Cement. PPC is a type of blended cement comprising Portland clinker, pozzolana particles and gypsum in certain specific proportions.

279) PPE (Personal Protective Equipment) – Equipment Worn to Minimize Exposure to a Variety of Hazards.

280) PQP – Project Quality Plan. sometimes referred to as a quality management plan, quality assurance plan or project quality management plan, is a project-specific quality plan that describes the activities, standards, tools and processes necessary to achieve quality in the delivery of a project

281) PR – Purchase Request. A purchase requisition is an internal document used by a department or individual within an organization to request the acquisition of goods or services. It is essentially a formal request.

282) Pre-Construction Services – Services Provided Before the Actual Construction Process Begins, Such as Design and Planning.

283) Procurement – The Process of Acquiring Materials, Equipment, And Services for a Construction Project.

284) Project Scope – The Defined Boundaries of a Construction Project, Including What is and is not Included in The Work to be Performed.

285) Project Stakeholder – An Individual or Organization that has an Interest in the Outcome of a Construction Project.

286) PRV – Pressure Relief Valve or Pressure Reducing Valve. A relief valve or pressure relief valve (PRV) is a type of safety valve used to control or limit the pressure in a system.

287) PTW – Permit to Work. A PTW system is a formal written system used to control and execute certain types of jobs safely, which are identified as potentially hazardous.

288) PVC – Price Variance (Price Escalation). The Contractor shall be reimbursed or shall refund to the Corporation as the case may be the variation in the value of the work carried out from time to time, depending on whether the prices of material and labour as a whole rise or fall.

289) PWD – Public Work Department. PWD is an Indian government agency responsible for building and maintaining public services, such as public government construction, highways, bridges, public transportation, drinking water sources, etc.

290) PWHT – Post Weld Heat Treatment. It reduces the levels of tensile residual stresses in a joint.

FRP Laminate structure for pipe and fittings

Two standard manufacturing methods are used in FRP laminate construction as an overwrap for thermoplastic piping systems: Filament Winding and Contact Molding (hand lay-up).

Pipes and fittings of Type D, as per DIN 16965 / 966 standards, consist of a Chemical Barrier Layer (CBL) with a minimum thickness of 2.5 mm and a structural layer filament-wound from woven roving, Chopped Strand glass mats, and unidirectional woven roving. Additionally, there is a bonding layer that connects the thermoplastic liner to the FRP structure. The top layer serves as exterior protection and includes a resin layer with paraffin wax and UV protection.

Below figure shows CBL, Structural layer, top layer.

For Chemical barrier layer (CBL):  Chemical barrier layer consists of Resin-rich layer with a gelcoat veil and chopped strand mats. It is having resin content 75 ± 5% and Glass content 25 ± 5%.

Structure layer: This layer is the primary structural portion of the laminate and is designed to withstand the loads caused by pressure, wind, seismic and other conditions. It consists of alternating layers of chopped strand.

Structured layer for pipes: Filament winded from roving, Chopped strand mats and woven roving. It will have resin content 40 ± 5% and Glass content 60 ± 5%.

Structured layer for fittings: Laminated from Chopped Strand mats and woven roving. It is having resin content 45 - 65% and Glass content 35 - 55%.

Top layer / Outer Surface Layer: The top veil is used for protection against all weather conditions, UV radiation, and chemical reactions. If the outer surface of a laminate is to be exposed to a corrosive environment, a veil layer or a chopped strand layer may be added over the structural layer for additional protection. The outer surface can also be pigmented for color designation if necessary.

For More Details about FRP click Here

For More Details about FRP Pipe click Here

Terminal Benefits of Construction Labour

Dear Readers,

Even though, the construction industry is the second largest employer in India, after agriculture. The casual nature of jobs in the unorganized construction sector can lead to poor working conditions, low salaries, and less job security. Construction projects are often located in remote sites, can be unpredictable, and there is a high chance of encountering unforeseen problems like weather. 

Terminal benefits are final entitlements of an employee upon termination of an employment contract. It is nothing but Money paid to an employee whose employment has been terminated because of a closedown or downsizing. 

Below Table shows the industrial practice of Terminal benefits for construction Workmen. A contingency has been included, which will be tailored to your requirements.

Please note that, if you leave the company on your own accord before the expiry of the notice period, you will not be eligible for retrenchment compensation as per the retrenchment notice already issued.

For costing, estimating, or rate analysis purposes, terminal benefit calculations are crucial to avoid significant crises. Calculating necessary cost provisions periodically and maintaining them can prevent financial crises and last-minute surprises.

For More Details about Basic Wages Click ABW

For More Details about Man Day & Man Hour Click Here

For More Details about Labour Welfare Click Here

For More Detail about Labour Law in India Click Here

Welding Terms Part-5 (I, J & K)

Dear Readers,

This is continuation of Part-4. This article will be a valuable resource for anyone looking to enhance their knowledge of the Welding Works.

Impact Test – A test in which one or more blows are suddenly applied to a specimen. The results are usually expressed in terms of energy absorbed or number of blows of a given intensity required to break the specimen.

IMPREGNATED-TAPE METAL-ARC WELDING – An arc welding process in which fusion is produced by heating with an electric arc between a metal electrode and the work. Shielding is obtained from decomposition of impregnated tape wrapped around the electrode as it is fed to the arc. Pressure is not used, and filler metal is obtained from the electrode.

Inclined Position – In pipe welding, the pipe axis angles 45 degrees to the horizontal position and remains stationary.

Incomplete Fusion – A weld discontinuity where fusion did not occur between weld metal and the joint or adjoining weld beads.

Incomplete Joint Penetration – A condition in a groove weld where weld metal does not extend through the joint thickness.

Indentation – In a spot, seam, or projection weld, the depression on the exterior surface or surfaces of the base metal.

Induction Brazing – A process in which bonding is produced by the heat obtained from the resistance of the work to the flow of induced electric current and by using a nonferrous filler metal having a melting point above 800 ºF (427 ºC), but below that of the base metals. The filler metal is distributed in the joint by capillary attraction.

Induction heating – Induction heating is the process of heating an electrically conducting object (usually a metal) by electromagnetic induction, through heat generated in the object by eddy currents.

Induction Welding – A process in which fusion is produced by heat obtained from resistance of the work to the flow of induced electric current, with or without the application of pressure.

Inert Gas – A gas that normally does not combine chemically with the base metal or filler metal.

Infrared radiation – Electromagnetic energy with wavelengths from 770 to 12000 nanometers.

Intergranular Penetration – The penetration of filler metal along the grain boundaries of a base metal.

Intermetallic – A term used to describe a compound material composed of two or more metals or of a metal and a nonmetal.

Intermittent Weld – An intermittent weld, also called a skip weld, consists of a series of welds placed on a joint, with unwelded spaces between each of the welds.

Inter-pass Temperature – In a multi-pass weld, the temperature of the weld area between passes.

Inverter – A power source for welding machines that is much more efficient than the normal transformers.

Ionization Potential – The voltage required to ionize (add or remove an electron) a material.

ITP – Inspection Test Plan. (Similar to FQP). It's a plan that lists what tests and inspections should be performed throughout each phase of a project.

Jig – Jigs hold the metal or steel you are working on in place as you are fabricating. They can be steel clamped with a vice or C-clamp, bolts tack-welded to a table, or very elaborate frames.

Joined buildup sequence – The order in which the weld beads of a multiple-pass weld are deposited with respect to the cross section of the joint.

Joint – The junction of members or the edges of members that are to be joined or have been joined.

Joint design – The joint geometry together with the required dimensions of the welded joint.

Joint efficiency – The ratio of the strength of a joint to the strength of the base metal (expressed in percent).

Joint geometry – The shape and dimensions of a joint in cross section prior to welding.

Joint penetration – The minimum depth a groove or flange weld extends from its face into a joint, exclusive of reinforcement. Joint penetration may include root penetration.

Joint welding procedure – The materials, detailed methods and practices employed in the welding of a particular joint.

Kerf – The width of the cut produced during a cutting process.

Keyhole – A technique of welding in which a concentrated heat source penetrates completely through a workpiece forming a hole at the leading edge of the molten weld metal. As the heat source progresses, the molten metal fills in behind the hole to form the weld bead.

Kilogram (kg) – The kilogram or kilogramme (SI unit symbol: kg) is the base unit of mass in the International System of Units (SI).

kW (Kilowatts) – A kilowatt is simply 1,000 watts, which is a measure of power. Primary kW is the actual power used by a power source when it is producing its rated output. Secondary kW is the actual power output of a welding power source.

Abbreviations Used in Construction Industry - Part 3 (G to L)

Dear Readers, 

This is continuation of Part-2. Successful project delivery includes both written and oral communication is more important. For communication it is mandatory to understand the acronyms and terms used in construction industry. 

Meanwhile, construction project management acronyms help streamline communication and increase efficiency between project managers, contractors, and other stakeholders.

151) GA – General Arrangement. A general arrangement drawing (GA drawing) is a contract document, which records information needed to understand the general arrangement structural elements on a project.

152) Galv. – Galvanized.

153) Gantt Chart – A Graphical Representation of a Construction Project Schedule, Showing Tasks, Dependencies, and Durations.

154) GC (General Contractor) – A Company That Manages and Coordinates the Construction Process from Start to Finish.

155) GCC – General Contract Clauses. It is a part of tender documents.

156) GCW – General Civil Works.

157) GFCI (Ground Fault Circuit Interrupter) – An electrical safety device that protects against electrical shock.

158) GI – Galvanised Iron.

159) GL – Ground Level.

160) Glazing – The Installation of Glass in Windows, Doors, And Skylights.

161) GMAW – Gas Metal Arc Welding. and flux cored arc welding (FCAW). sometimes referred to by its subtypes metal inert gas (MIG) and metal active gas (MAG)

162) GMP- Guaranteed Maximum Price – This is the maximum amount of labour, materials, and profit costs that a contractor can charge for a project.

163) GPR (Ground Penetrating Radar) – A technology used for subsurface imaging in construction.

164) Grading – The Process of Creating a Level Surface on a Construction Site.

165) GRP – Glass Reinforced Plastic / Polymers / Polyester.

166) GTAW – Gas Tungsten Arc Welding. Also known as tungsten inert gas (TIG) welding.

167) GWL – Ground Water Level.

168) Hardscaping – The Design and Construction of Non-Vegetative Elements in Outdoor Spaces, Such as Patios, Walkways, And Retaining Walls.

169) HL – High Level.

170) HR – Human Resources.

171) HRS – Hot Rolled Steel.

172) HSE / EHS / SHE – Health, Safety & Environment. 

173) HSFG – High Strength Friction Grip. One type of fastener.

174) HSS – Hollow Structural Section.

175) HT – High Tensile.

176) HV – High Voltage.

177) HVAC (Heating, Ventilation, and Air Conditioning) – The Systems and Components of a Building That Provide Heating, Cooling, and Air Circulation.

178) ICE – Institution of Civil Engineers.

179) ICT – Institute of Concrete Technology

180) ID/OD- Inside Diameter/Outside Diameter – For piping, the inside diameter refers to the width of the pipe opening. The outside diameter is the sum of the inside diameter and twice the pipe wall thickness.

181) IDCT – Induced Draft Cooling Tower.

182) IFB – Information for Bidders. It is a sealed bidding process used when a department has a clear description of the project scope, requirements, and proposer qualifications.

183) IFC – Issued for Construction. “IFC” means the Contractor's Documents to be issued for construction of the Works that have been subject to all necessary approvals, verification, certification and release of applicable Hold Points required under this Contract.

184) IIE – Institute of Industrial Engineers.

185) IL – Invert Level.

186) In. – Inch.

187) IPS flooring – IPS flooring stands for Indian patent stone flooring, it is a basic type of flooring which provides good wearing properties.

188) ITB – Invitation to Bid. It is an official document issued by a project owner that targets contractors to solicit bids for a construction project. The ITB provides all bidders with information about the project including scope, duration, submission guidelines and minimum qualifications.

189) ITP – Inspection Test Plan. (Similar to FQP). It's a plan that lists what tests and inspections should be performed throughout each phase of a project.

190) ISBL – Inside Battery Limit. It is the barricading of work limits.

191) ISO – International Organisation for Standardisation

192) ISO Drg. – Isometric Drawing used for Piping works.

193) IoT (Internet of Things) – The Integration of Devices with Internet Connectivity to Collect and Exchange Data.

194) JCB – J C Bamford (plant manufacturer) Construction equipment manufacturer. World leaders in backhoe loaders and telehandlers.

195) JCR – Job Cost Report.

196) JD – Job Detail or Job Description. This is a written summary of the responsibilities, activities, qualifications, and skills required for a job position.

197) Jt. – Joint. 

198) JV – Joint Venture. JV is a business arrangement in which two or more parties agree to pool their resources for the purpose of accomplishing a specific task. This task can be a new project or any other business activity.

199) Kg. – Kilogramme.

200) KoM – Kick Off Meeting. (KoM) was to create the basis for a smooth project development, to review the overall Project timetable and to fine tune the work of the Consortium. After welcoming the participants, the meeting agenda was approved by the Consortium.

201) KPI – Key Performance Indicators. It is a measurable and quantifiable metric used to track progress towards a specific goal or objective.

202) kW – Kilowatt.

203) LC – Letter of Credit. A Letter of Credit (LC) is a document that guarantees the buyer’s payment to the sellers. It is issued by a bank and ensures timely and full payment to the seller.

204) LD – Liquidated Damages – While drafting a contract, these are damages for an injured party to collect compensation for a breach of contract. In construction contracts, a contractor is often charged LDs for each day that a project goes beyond the agreed-upon completion date.

205) Landscaping – The Design and Construction of Outdoor Spaces, Including Plants, Trees, And Other Vegetation.

206) LEED (Leadership in Energy and Environmental Design) – A Certification System Recognizing Best-In-Class Building Strategies and Practices.

207) LHS – Left Hand Side.

208) Lifecycle Cost Analysis – The Analysis of The Total Cost of a Construction Project Over Its Lifetime.

209) LL – Live Load.

210) LMP – Labour, Material, Plant and Machinery. These are the basic requirements of Resources.

211) LNG – Liquefied Natural Gas. It is natural gas that has been cooled down to liquid form for ease and safety of non-pressurized storage or transport.

212) LOA – Letter of Authorisation. It is a legal document in which the executing party makes certain assertions to a service provider about their authorization.

213) LOD (Level of Detail) – The Level of Detail Required in a Construction Document or Model.

214) LOI – Letter of Intent. Letter of Intent is a document declaring the preliminary commitment of one party to do business with another party.

215) LOP – Loss of Pay.

216) LOTO – Lock-Out, Tag-Out. This is a set of procedures that are used to ensure that equipment or systems are shut down, inoperable, and (where relevant) de-energized prior to any maintenance or repair work.

217) LPG – Liquefied Petroleum Gas. Also called liquid petroleum gas is a flammable blend of hydrocarbon gases applicable for fuel in heating, cooking, and automotive appliances.

218) Lqd. – Liquid.

219) LS – Lumpsum – Strictly speaking, a lump sum is a single payment of money instead of payment instalments.

220) LTI – Lost Time Injury. (LTI) is something that results in a fatality, permanent disability, or time lost from work. It could be as little as one day or a shift off work being lost, or months of rehabilitation.

Time & Change Management

Dear Readers,

When you have promoted from your current position, your income, facilities and responsibilities will raise. Simultaneously, your working team size will also grow. You will connect with more people than ever before.

As all these grow, the essential ingredient, time does not grow. It is used to be 24 hours and it's the same now.

So, it creates a lot of pressure. A compulsion develops to produce maximum results in a short period of time and the nature of work is also changing.

As we move up the ladder of an organization, our work habits change and our work ethic also changes. However, there is still involvement in that old activities, what we had so far. It is little difficult to break free from that old assignments/works immediately. Even if someone has been hired/assigned to deal with the old work. We like to interrupt again because of these habits.

Thus wastes his time and ours as well. Except ourselves, there is no one else to do the work for the new responsibility. Hence, note that another job or responsibility can be taken up only after leaving the old job or responsibility.

Let us See the scenario in any industry.

Initially a worker duty is to produce goods. As he performed well, respecting his skill and hard work, the company promotes him and appoints him as a supervisor.

With the new position comes along with new responsibilities, like training others and supervising them, he needs to spend more time on these. Apart from this, he may require some time for planning activities of production (Works), strengthening the relationships with other departments, etc.

When the next promotion makes him as a manager, the responsibilities of this position require a different kind of performance from him. Now he spends more time on planning, overseeing coordinated operations, preparing his subordinates to handle more responsibilities. The previous supervisory function and direct involvement in production should be reduced (avoided).

The work is still different when the next management level is reached like strengthening external contacts and their relations. Duties such as analyse the market, Prepare and formulate appropriate growth strategies and preparing for the company's next phase of growth will become the main task.

If you want to spend more time on exclusive activities in the respective levels, it can only be done if other duties are avoided.

There is no change in the fact that there are 24 hours in a day. However, many people do not feel like leaving other duties aside.

He wants everyone to think that he is important, that’s why he doesn't want to tell anyone that he can't.

All this combined with the desire to make everyone happy reduces the amount of time available for specific tasks.

This means that time management is really self-management. By managing our activities, we can manage time.

Whether we like it or not, this moment won't stop. We have a choice to change with something, with what to change, but not to change. That is why we should be careful.

Some people exchange their time with the comfort of sleeping. Still others substitute it for entertainment, recreation and amusement. Some others alternate with noble actions and actions that result in great accomplishments.

Hence, time Management and changes are more important in professional life.

Welding Terms Part-4 (G&H)

Dear Readers,

This is continuation of Part-3. Welders can be found working in manufacturing plants, building job sites, and rebuilding infrastructure such as bridges and highways. Being able to move from industry to industry offers a higher level of job security than many other types of jobs. it’s useful to know some terms of Welding.

Galvanized – An electrochemical process where mild steel is hot-dipped into liquid zinc to make it anti-corrosive.

Gas Carbon-Arc Welding – An arc welding process in which fusion is produced by heating with an electric arc between a carbon electrode and the work. Shielding is obtained from an inert gas such as helium or argon. Pressure and/or filler metal may or may not be used.

Gas Metal Arc Welding (GMAW) – An arc welding process where the arc is between a continuous filler metal electrode and the weld pool. Shielding from an externally supplied gas source is required.

Gas Pocket – A weld cavity caused by the trapping of gases released by the metal when cooling.

Gas Tungsten Arc Welding (GTAW) – An arc welding process where the arc is between a tungsten electrode (non-consumable) and the weld pool. The process is used with an externally supplied shielding gas.

Gas tungsten arc welding-pulsed arc (GTAW-P) – A variation of the gas tungsten arc welding process in which the current is pulsed.

Gas Welding – Welding with the heat from an oxy-fuel flame, with or without the addition of filler metal or pressure.

Globular Transfer – A type of metal transfer in which molten filler metal is transferred across the arc in large droplets.

Goggles – Safety equipment worn to protect the welder’s eyes from harmful radiation while welding and cutting.

Gouging – The forming of a bevel or groove by material removal.

Groove – An opening or channel in the surface of a part or between two components which provides space to contain a weld.

Groove angle – The total included angle of the groove between parts to be joined by a groove weld.

Groove face – That surface of a member included in the groove.

Groove radius – The radius used to form the shape of a J- or U-groove weld joint.

Groove type – The geometric configuration of a groove.

Groove Weld – When a very strong weld is needed, such as where two columns are spliced together on a high-rise, it is important to get the maximum penetration and fusion. This is done by cutting a Bevel so that you can weld solid from the Root to the face of the parent metal. Examples: single V, single U, single J, double bevel etc.

Ground Connection – A safety connection from a welding machine frame to the earth. Nothing but earthing.

Ground Lead – When referring to the connection from the welding machine to the work, see preferred term Workpiece Lead.

GTAW – Gas Tungsten Arc Welding. also known as tungsten inert gas (TIG) welding.

Guided Bend Test – A bending test in which the test specimen is bent to a definite shape by means of a jig.

Hammer Welding – A forge welding process.

Hand shield – Also called face Shield. A protective device, used in arc welding, for shielding the eyes, face and neck. A hand shield is equipped with a suitable filter plate and is designed to be held by the hand.

Hard Facing – A particular form of surfacing in which a coating or cladding is applied to a surface for the main purpose of reducing wear or loss of material by abrasion, impact, erosion, galling, and cavitation.

Hard Surfacing – The application of a hard, wear-resistant alloy to the surface of a softer metal.

Hardening – This term refers to a process used to increase the hardness of metal, typically iron-based alloys, by heating it above a certain critical temperature range and then rapidly cooling or “quenching” it.

Heat-Affected Zone (HAZ) – That section of the base metal, generally adjacent to the weld zone, whose mechanical properties or microstructure, have been altered by the heat of welding.

Heat Time – The duration of each current impulse in pulse welding.

Heat Treatment – An operation or combination of operations involving the heating and cooling of a metal or an alloy in the solid state for the purpose of obtaining certain desirable conditions or properties.

Helmet – protection equipment worn to protect the welder’s face and neck.

Hermetically Sealed – Airtight. Heterogenous – A mixture of phases such as: liquid-vapor or solid-liquid-vapor.

Hertz – Hertz is often referred to as "cycles per second." In the United States, the frequency or directional change of alternating current is usually 60 hertz.

Hold time – The time that pressure is maintained at the electrodes after the welding current has stopped.

Horizontal Weld – A bead or butt-welding process with its linear direction horizontal or inclined at an angle less than 45 degrees to the horizontal, and the parts welded being vertically or approximately vertically disposed.

Horn – The electrode holding arm of a resistance spot welding machine.

Horn Spacing – In a resistance welding machine, the unobstructed work clearance between horns or platens at right angles to the throat depth. This distance is measured with the horns parallel and horizontal at the end of the downstroke.

Hot Crack – A crack formed at temperatures near the completion of weld solidification.

Hot Pass – In pipe welding, the second pass which goes over the root pass.

Hot Short – A condition that occurs when a metal is heated to that point, prior to melting, where all strength is lost but the shape is still maintained.

Hydrogen Brazing – A method of furnace brazing in a hydrogen atmosphere.