Common Plumbing Processes PDF

PowerPoint 1 Procedures for measuring and bending plumbing tubes  LESSON INTENT Learners will be able to describe and identify the following processes and methods: Procedures for measuring and bending plumbing tubes Equipment used in measuring Identify the S...

PowerPoint 1 Procedures for measuring and bending plumbing tubes  LESSON INTENT Learners will be able to describe and identify the following processes and methods: Procedures for measuring and bending plumbing tubes Equipment used in measuring Identify the SI units for measurement Use items to measure accurately Convert millimetres to centimetres to metres Bending and Fabricating Pipework Jointing Methods for different types of pipe The units of measurement plumbers use are: Millimetres = mm (Centimetres = cm) Metres = m 10mm = 1cm 1,000mm = 1m Steel rule: for accurate pipework measurement and bending Tape measure: pipework installation or measuring large pipe lengths Site tape: site measurements or room measurements Laser distance metre: quick room measurements Material 1 Copper Microbore Scissor type Stand bender: hand bender: bender: R250 half hard R220 soft R250 half hard copper 28 and coiled copper copper 15 and 32mm 6,8,10mm 22mm  Internal and Electric tube external benders, either springs hand or stand mounted  Grades of copper Sometimes need protection against soils or atmospheres. Old New BS2871 BSEN1057 Type Diameters (mm) Table W R220 Coiled microbore (heating) 6, 8, 10 Table X R250 Half hard straight lengths 15-54 domestic 6, 3, 2, 1m lengths Annealed coils for Table Y R220 underground 15-22 underground 25m lengths Table Z (R290) Hard thin walled Not commonly available now Water (wholesome) Water (other) Gas (natural) Central heating Chrome decorative Minibore/microbore: 6, 8, 10mm Small bore: 12, 15, 22mm Large bore: 28mm and larger When copper is purchased, the half hard copper R250 can be bought in 3 or 6m straight lengths. (Table X). Soft, minibore R220 copper is bought in coils of 10 or 50m. Protecting copper pipe is important in vulnerable areas – plastic coated, denso tape etc. Copper is most vulnerable when laid in concrete flooring and when it emerges from the floor.  Gas Water General purpose, inc. central heating Wholesome water Main purpose of coating the pipes is for protection and identification. The main purpose of chrome- coated copper pipe is for the finish. Bending copper tube Soft coils (R220 Table Y) and half hard (R250 Table X) copper tube can be bent by using: Bending springs (internal or external) Hand bender (micro and small bore) Machine floor-standing bender (max 42mm) Advantages of bending pipe, rather than using a fitting: Less frictional resistance Costs less Sections can be prefabricated in one go Bending springs Internal and external bending springs are not used much today. They are occasionally used by plumbers when trying to bend an existing piece of pipe without creasing it. Bending springs The spring is tightened by twisting a bar through the end of the spring. The spring bend is normally over-pulled and then eased back to 900 to make spring withdrawal easier. Slightly over-pull for a 900 bend Internal bending spring The bar is used to tighten the spring to make removal easier All bends appear to gain material on one side and compress material on the other. It is possible to accurately work out the length of pipe to be bent, in relation to fixed points, by finding out the length of pipe the bend actually occupies. The radius centre line is normally 4 x the diameter of the pipe (4D). Radius x 2 x 3.14 4  Example 300mm Radius Work out overall length of pipe 150mm 60mm Radius x 2 x 3.14 4 60 x 2 x 3.14 4 = 94.2mm 94 + 300 + 150 = 544mm 300 450 900 Golden rules Select the measuring method: Back to back Centre to centre Back to inside Inside to back “Measure twice, cut once or bend once” If a section needs two or three bends, ensure the firs bend is correctly positioned in the bender before pulling the second.  Tools Scissor type bender and Steel rule (mm) slips Engineers square Senior/junior Pencil hacksaw 32tpi Common bends 900, 450 Offset Back to back Half pass over (kick over) Full pass over  X dimensions This is a term used by Yorkshire manufacturers to work out how much copper tube is required, providing you know the centre-to-centre measurement. X dimension = centre of fitting to the engaged length If you know the type of fittings being used, along with the centre-to-centre distance, taking off 2 x dimensions will give the pipe length.  X dimensions Copper cut length X dimensions taken off Centre to centre distance  Material 2 Low carbon steel Hydraulic bender  Grades Grade Colour Use Heavy Red Steam and fire systems Medium Blue Heating and oil lines Light Brown Gas When LCS is secured in position, munson rings are commonly used. LCS is made from 99.85% iron and 0.15% carbon. Manufactured to BS1387 1984 and supplied in: Self colour Painted black Red Oxide paint Galvanised All grades have the same outside diameter – the heavier the grade the smaller the bore. Diameters are imperial and lengths are metric. Can be jointed by threading, welding and special compression joints. Threads are tapered and parallel (BSPT) and are sealed by PTFE, red paste or hemp and paste.  Protection Galvanized (Inside and outside) Denso tape (Wrapped outside only) Paint (Outside only) Chemical (Inside only)  Pump handle The frame Air inlet Hydraulic Ram head cylinder Location Stops lugs Golden rules When bending, it stretches in both directions. LCS stretches by its nominal bore: ½in = 15mm ¾in = 20mm Level the hydraulic bender when doing multiple bends Set stops in correct position Use correct size on ram head Allow for spring back after pulling a bend – one full pump  Tools Hydraulic Engineers bender square Steel rule (mm) Senior hacksaw 32tpi  Common bends 900, 450 Off set Half pass over (kick over) Nowadays, commercial LCS is commonly fabricated, using fittings rather than bending.  Z dimensions These are identical to X dimensions in copper, but they are referred to Z dimensions in LCS. All Z dimensions are referenced from manufacturers’ catalogues. George Fischer Crane  Threading A common site method used to thread LCS is by using a free-standing threading machine. Training is required before using this type of machine. The LCS is placed into a chuck which grips the tube. The chuck rotates, allowing the operator to either cut or thread the LCS.  Threading Another method of threading LCS is by using a handheld threader. A clamp is secured onto the LCS. The handheld threader rotates the dies, allowing the operator to thread the tube, as the threader moves down the clamp arm.  Threading A final method is by using a handheld die. This is a manual operation using a ratchet head and a lever arm to thread the LCS. Threading With any of the threading methods, a set of four hardened dies with the appropriate thread is used: ¼in BSP, ½in BSP, ¾in BSP, 1in BSP and 1¼in BSP etc. When cutting the threads, it is important to lubricate the cutting action with oil. Cutting produces burrs that are sharp and care needs to be taken when cleaning the heads. If any cutting of LSC tube is required, the first job should be to file off any burrs: de-burr. Material 3 Plastic  Tools Deburring Tool Ratchet style cutter for waste pipe Steel rule Pipe cutter for polybutylene Grades There are many different plastic that plumbers use on a daily basis. They can be used for cold water, hot water, central heating, guttering, above ground drainage and below ground drainage. Thermoplastic Made from polymer resin. Can be heated and re- shaped, but when frozen becomes brittle (guttering). These plastics are recyclable. There are many types which are suitable for different situations. PVCu Unplasticised polyvinyl Not suitable for hot water chloride Solvent weld Cold water Push fit Soil pipes Waste and overflow pipes Guttering and downpipe MDPE Medium density polyethylene Degrades in sunlight Underground mains (blue) Fusion welded CWSC Push fit Compression HDPE High density polyethylene Degrades in sunlight Underground mains (black) Fusion welded Push fit Compression Polypropyle Waste pipes Degrades in direct sunlight ne Overflow Feels slightly greasy to touch CWSC Not solvent welded Polybutylene Cold water Push fit Hot water Compression Central heating Not solvent welded ABS Commercial water Solvent welded Acrylonitrile Waste Degrades in sunlight Butadiene Overflow Styrene  Bending Plastic pipe is usually fabricated using fittings on waste pipes. Polybutylene (hot, cold and central heating) is flexible and can be laid around corners, if supported. Golden rules Allow for expansion and contraction Always remove burrs after cutting Extra support and clipping required if hot water conveyed Ventilation required if solvent welding Sunlight degradation due to UV (yellowing on uPVC; pressure pipe disintegrates; soil pipe above (PVCu – grey) and below ground (PVC brown) Support sleeves (inserts) for pressure pipe Barrier pipe for conveying wholesome water X dimensions On plastic, the X dimensions are manually measured and worked out. Some manufacturers now state the X dimensions in their catalogues. Soil and waste plastic PVCu plastic is used for push fit and solvent welded soil, waste pipes, overflow pipes, guttering and below ground drainage. 110mm, 50mm, 40mm, 32mm and 21.5mm. Soil and waste plastic Modified uPVC is used for solvent welded waste and overflow pipes. It is much more durable than PVCu and performs better than other plastics, especially at high temperatures. 50mm, 40mm, 32mm and 21.5mm. ABS is used for soil and waste pipes because of its toughness. It degrades when exposed to UV light.  Soil and waste plastic Polyethylene (PE) is used a lot in the plumbing trade. Medium density polyethylene (MDPE), is hardwearing and is used for water mains (blue) and gas mains (yellow). It degrades when exposed to UV light. 20mm-63mm in coils. The most common is 25mm cold water service pipe. High density polyethylene (HDPE), was used some years ago and is still found in properties but it was superseded by MDPE.  CHECK YOUR KNOWLEDGE WITH THESE QUESTIONS. 1. What grade of copper is small bore? 2. What is the grade of 15mm copper pipe? 3. What is the golden rule of measuring and cutting? 4. What are some of the most common types of copper bends? 5. What is uPVC used for? 6. What is this tool used for? 7. What is this tool used on?  TRAFFIC LIGHT IT: WHERE IS YOUR LEARNING AT? Red = I have not really understood the content we have studied today (write down 2 questions that you need help with) Amber = I have understood the content on Effective Questionning (write down 1 one question you need to clarify) Green = I have understood all the content (write down one example from what we have studied)