The new surface offers the advantages of reduced friction and greater wear resistance.

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Terence Neal
5 years ago
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1 ER 10 Hydraulic Pit Props The photograph shows several of these components, each of which measures 1.5m (5 feet) long by 15.24cm (6 inches) in diameter. The have been sprayed with a deposit of S2 with a finish thickness ranging from 0.4mm (0.016 ) to 1mm (0.040 ). The new surface offers the advantages of reduced friction and greater wear resistance. The photograph shows the components before finishing; the work was carried out using a Metallisation Arcspray system.

ER 11 Armature Shaft Falmouth Dry Dock The armature shaft, on the N o 2 main pump motor head, became so badly worn as to be unserviceable. A deposit of S20/S2 chrome steel was sprayed to a depth of 2.

2 ER 11 Armature Shaft Falmouth Dry Dock The armature shaft, on the N o 2 main pump motor head, became so badly worn as to be unserviceable. A deposit of S20/S2 chrome steel was sprayed to a depth of 2.5mm (0.100 ) using the Arcspray system. No disconnection of the armature windings was necessary, a simple cardboard mask preventing the ingress of metal dust during spraying, and after remachining the component was back in service in less than 24 hours.

ER 12 The above photograph shows an electric motor armature reclaimed on the journal area. The work was carried out using a Metallisation Arcspray Unit and a deposit of 2.54mm (0.

3 ER 12 The above photograph shows an electric motor armature reclaimed on the journal area. The work was carried out using a Metallisation Arcspray Unit and a deposit of 2.54mm (0.100 ) of S2 was applied. The repair was completed in approximately 36 hours as opposed to a delivery period of several months for a new unit. The cost of reclamation was about 1% of the cost of replacement.

ER 13 Arc Spraying Reclaims Marine Piston The illustrated piston from a massive marine diesel engine provides an interesting example of more than one characteristic of arc spraying.

4 ER 13 Arc Spraying Reclaims Marine Piston The illustrated piston from a massive marine diesel engine provides an interesting example of more than one characteristic of arc spraying. The piston, which is 508mm (20 ) in depth and approximately 305mm (12 ) in diameter, came from a marine engine that had been in use for a considerable number of years, it was not possible to obtain a replacement. The outer surface was so badly worn that an overall deposit of 1.56mm (1/16 ) on the radius was necessary, with heavier build-ups in localized areas where the wear was excessive. Before spraying, the piston was machined and the recessed areas were masked with a Sprayshield masking compound to prevent adhesion of the sprayed deposit in these areas. A bond coating of aluminium bronze was deposited without any prior gritblasting, followed by a final deposit of S20/S2 steel. After spraying, the piston was machined and ground to finished size. A point, which is well brought out by the photograph, is the sharp definition, which was achieved on the edges of grooves, holes and recessed surfaces.

5 ER 14 Fork lift Brake Drum and Earth mover brake drum clutch housing Using a Metallisation Arcspray system depositing S20 Steel these components have been repaired.

ER 15 Heavy wear - Underground The wear and tear on the expensive underground equipment used by the mining industry is very considerable indeed, particularly at the coalface where mammoth automatic

6 ER 15 Heavy wear - Underground The wear and tear on the expensive underground equipment used by the mining industry is very considerable indeed, particularly at the coalface where mammoth automatic cutters have taken over from the miner. An example of, wear on the machinery, is provided by the main drive head shafts of the coal rippers. One end of the shaft carries the drive, and the other end carries the Meter (5ft) diameter cutting head, which rips into the coal seam at the face. The drive shaft is keyed to accept the cutting head mechanism, and it is at this point that the wear is most severe, the photograph shows clearly the size and position of the keyway; wear takes place around the bearing circumference, and particularly at the keyway edges, which carry the full weight and impact shock of the cutting heads. In the metal spraying rectification of these shafts, any wear of the actual keyway is repaired first of all by re-welding and re-cutting to standard size. The surfaces of a number of such shafts have been reclaimed. A deposit of S2 1.5mm (0.060 ) thickness has been applied using the Metallisation Arcspray system.

ER 16 Reclamation of Aluminium Taper Rollers A batch of twenty four conveyor rollers which provide a hot strip delivery system in an aluminium strip mill has been treated by metal spraying after

7 ER 16 Reclamation of Aluminium Taper Rollers A batch of twenty four conveyor rollers which provide a hot strip delivery system in an aluminium strip mill has been treated by metal spraying after showing severe signs of wear. The rollers are designed with a double taper so that as the aluminium strips cool, they run progressively towards a central point. The taper can be seen in the photograph. In addition to wear on the roller surface itself; the carrying spindles were also severely worn. A deposit of S2 was applied to the rollers, followed by some skilful finishing. The taper towards the centre section meant that the tailstock of the lathe had to be offset, the rollers being steadied on the parallel centre section to facilitate the skilled lathe work. With an overall length of 3 Meters (10ft) working faces of 2.44 Meters (8ft) a diameter decreasing from 315mm (12½ ) to 292mm (11½ ) and a weight of 508 Kg (10 cwt) each, the twenty-four rollers together represented a considerable capital item to the aluminium mill concerned. A further example of the remarkable savings; by the reclamation of badly worn engineering component.

8 ER 17 In Hong Kong a Metallisation Arcspray Unit, supplied to the Kowloon Motor Bus Co. Ltd, is used to reclaim worn brake drums and engineers quickly recognize the significance of this application, as the drums are subject to considerable expansion and contraction from heat during use. The drum is first rough turned and a bond coating of is applied, followed by a deposit of S20/S2 Steel after which the surface is finish turned to size. The application would be impossible with a Flamespray pistol, the improved cohesion and adhesion of the Arcspray deposit ensures full adhesion during expansion and contraction

ER 18 Crane Wire Barrel During final machining one section of this crane wire barrel was accidentally reduced by 12.5 mm (½ ) beyond the required diameter.

9 ER 18 Crane Wire Barrel During final machining one section of this crane wire barrel was accidentally reduced by 12.5 mm (½ ) beyond the required diameter. It was impossible to reduce the rest of the barrel to the same diameter because of the strength factor. Metal spraying was used to build up the surface of the mis-machined area back to the originally specified diameter. A continual groove was then machined into the barrel to accept the feed of the wire rope. The Metallisation Arcspray specification was a bond coat followed by a build up of S20 to the required thickness, i.e. a 6.25mm (¼ ) on the radius. It will be appreciated that the service conditions in which the barrel operates together with the constant squeezing action of the rope places a considerable load on the metal sprayed deposit; the surface has stood up to the treatment in a perfectly satisfactory way.

ER 19 Soap Chilling Cylinder The surface of this massive soap-chilling cylinder had been badly scored by the action of a stainless steel scraping blade used during the soap production process.

10 ER 19 Soap Chilling Cylinder The surface of this massive soap-chilling cylinder had been badly scored by the action of a stainless steel scraping blade used during the soap production process. A Metallisation Arcspray system was used to carry out an on the spot repair with the cylinder revolving in its own running bed, thus eliminating expensive dismantling and transport costs. During a thirty-hour period, a radial deposit of 3.175mm (0.125 ) of S2 was applied, this material being chosen in order to improve the wear characteristics of the cylinder in relation to the stainless steel scraper blade. After spraying, the surface was machined and ground down to a highly polished finish. The cylinder is Meters (5 6 ) in diameter, 1.89 Meters (6 0 ) long and weighs 3055Kg (3 tons). The soap manufacturer concerned was quoted a twelve-month delivery for a new cylinder; the metal spraying process had the cylinder back in operation in one week at a fraction of replacement cost.

ER 20 Engineering reclamation in mines Three examples of components of a Dosco Miner Machine that has been successfully reclaimed using a Metallisation Flamespray Pistol in the Central Workshops of

11 ER 20 Engineering reclamation in mines Three examples of components of a Dosco Miner Machine that has been successfully reclaimed using a Metallisation Flamespray Pistol in the Central Workshops of the NCB at Midlothian,UK. From left to right the components are A rear jack assembly piston, a hydraulic motor piston and an arcing cylinder piston rod. All the components have received a bond coating of followed by a final deposit of either S2 or 80E.

12 ER 21

ER 21 Ships White Metal Bearing This White Metal Bearing was flame metalsprayed in Australia during June 2005. The bearing has a diameter of 450mm and a length of 350mm.

13 ER 21 Ships White Metal Bearing This White Metal Bearing was flame metalsprayed in Australia during June The bearing has a diameter of 450mm and a length of 350mm. The bearing is from the P&O Cruise Liner- Pacific Sky. The Pacific Sky caters for 1550 passengers on 11 decks and is 240m long. The ship was built in 1984 weighs 46,000 tonnes and has a top speed of 21 knots.

14 ER 1 Run Out Roller A run out roll from a Steel Works being resurfaced with a deposit of S2 Steel applied by a Arcspray system. Many of these rollers have been reclaimed by this method with deposits of up to 12.7mm (½ ) thick, in most cases saving up to 60% of the cost of a new roll and of course being back in service within a matter of hours.

TABLE OF CONTENTS PART 7 - MACHINERY AND MACHINERY GUARDING

TABLE OF CONTENTS PART 7 - MACHINERY AND MACHINERY GUARDING Page DEFINITIONS...7-1 SAFEGUARDS...7-1 GUARDING...7-2 PULLEYS, BELTS AND BELT-SHIFTERS...7-3 CONTROLS...7-3 FLYWHEELS...7-3 GRINDING WHEELS...7-3