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Filters for metalworking
Tried and tested Real financial and operating benefits are claimed for a recently announced range of cutting fluids. They have been formulated "to meet changing and more stringent environmental regulations" and "to cope with the higher cutting speeds created by improvements in machine design, operating techniques, and the types of metal to be cut." After four years of development and testing, Mobil have launched three series of cutting fluids: Mobilmet 100 soluble oils; Mobilmet 450 non-corrosive straight oils; and Mobilmet 700 active neat oils. They have also extended their range of anti-mist oils. Soluble oils
The soluble oils, branded Mobilmet 120, 140, 150, and 170, are nonphenolic, sodium nitrite free fluids based on solvent refined mineral oil and containing rust inhibitors and a non-phenolic biocide. They are claimed to form stable emulsions with a wide range of water qualities and to give long service life when used for recommended applications. During field trials, Mobilmet 120 was tried in the machine shop of a large electrical goods manufacturer. Microbial degradation of a variety of soluble oils, accelerated by inaccessible sumps which made regular maintenance difficult, resulted in a charge life of 2-4 weeks. Use of Mobilmet 120 has resuited in the charge life being extended to, and maintained at, 12 weeks. The manufacturers suggest that two of the fluids in the series, Mobilmet 150 and 170, may be used in operations where neat oils are more common. They recommend 150 for medium to heavy duty cutting and grinding where straight oils were used, and 170 for applications which usually involve ep oils. Neat oils
The Mobilmet 450 series consists of a range of light coloured, multi-service, non-corrosive to copper, straight oils. The range covers machining operations on most materials having Brinell hardness up to about 300. In critical opera-
Testing a crankshaft using the Vitosonics crack depth gauge. Powered by a rechargeable battery, the gauge can measure cracks up to l OOmm deep in metals o f low electrical conductivity, such as iron and steel. The single probe, suitable for most applications, has spring loaded contacts to conform to uneven or curved surfaces. Vitosonics Ltd, Marshgate Drive~ Hertford SG13 7AN, UK tions, however, on draggy, difficult-tomachine materials an active oil is recommended. The 450 series oils are also suitable as machine tool lubricants and hydraulic fluids. Leaking lubricant and hydraulic systems will not cause contamination problems or deplete the additive concentration. Five active neat oils comprise the Mobilmet 700 series. They contain sulphurised and chlorinated additives and are formulated to give multi-metal and multi-operation capability. Mobil have also announced three antimist oils: Mobilmet 826, dark coloured active oil, and Mobilmet 424 and 427 which have similar performance characteristics to the 450 series. These oils are claimed to give performance levels equal or superior to conventional oils used for the same applications, while reducing oil mist. They are said to help create a healthier working environment, to reduce plant cleaning costs, and to eliminate the need for costly ventilation units. Mobil Oil Company Ltd, Mobil House, 54/60 Victoria Street, London SWlE 6QB, UK
Filters for metalworking Particles as small as 0.1 microns can be removed from metalworking coolants using a recently announced pressure leaf filter. The system is said to be particularly useful where different specifications for filtration of rolling oils, drilling tower coolants, etc call for a flexible basic system. Durco Europe's range of pressure leaf filtration equipment can be equipped with woven wire screens and fabrics to deal with particles as small as 0.1 microns. The falters can be produced in a variety of metals, including stainless steel, titanium, and Hastalloy, according to the application. For rolling oil and coolants Durco generally offer a fdtration quality of 5-0.5 microns, although screens and fabrics to deal with particles as small as 0.1 microns are available. Durco horizontal tanks, which are recommended for metal working applications, can be cleaned without opening the tanks. The filter leaves in the tank are attached to a pneumatically driven vibrator which shakes the dry
TRIBOLOGY international June 1977
141
cake off the leaves. No filter cloth is therefore required. Systems for cold rolling mills can be fully automated. The 'brain' of the system is an automated panel which monitors feed tank levels, flow control, fdtrate particle count, etc. Since feed tank oil can contain such diverse objects as tools; bottles, etc, Durco generally use a coarse screen prior to the fluid entering the system. For cleaning and maintenance, high accessibility to the filters is possible by virtue of a wheel mounted sliding casing. All vulnerable parts (pipes, valves, etc) are connected to the nonmoving head thus eliminating the risk of breakage. Durco Europe SA, Rue Verte 216-226, Box 7, B-1030 Brussels
Continuous grease injector Self-contained greasers which supply a continuous controlled flow of lubricant are claimed to avoid both the expense of centralised systems and the spasmodic delivery characteristic of hand-held guns. The continuous low pressure helps keep bearings clean by avoiding back flow of contaminants. The range of Greasomatic injectors has recently been extended to give operating lives of up to 12 months. Six standard grease fillings and three oils are available.
Pressure leaf filer for rolling oils and metalworking coolants
adaptors are available for other locations. Low pressure operation Under normal working conditions, Greasomatics operate at low pressure. If, however, old lubricant has stiffened in a neglected bearing, pressure builds up until the obstruction is cleared. In the case of complete blockage, the pressure will build up to about 10 atm, at which level the plastic base cone few ctive ~ents
Greasomatics are disposable, self-ejecting cannisters containing 120cc of grease or oil which is discharged at a constant rate throughout its working life. The manufacturers claim that life can be predicted accurately, providing the ambient operating temperature is known. Cannisters are pressurised by an electrochemical reaction. An activating screw breaks the seal between the zinc and carbon capsules and a 30% caustic potash solution. The reaction generates hydrogen in the rubber expansion chamber, extruding the lubricant into the bearing. The lubricant outlet has a ¼in BSP male thread to fit a standard grease nipple socket:
142
onsion ~nber :trolyte on assembly :ating ring ricant 'nber
:ating ring .=ors here when leant is spent ~read . . . . . . . . v, ~l¢J
Hydrogen evolved by an electrochemical reaction pressurises the lubricant in the Greasomatic continuous injector
TRIBOLOGY international June 1977
will tear, and the ejected lubricant will indicate the failure. Discharge rates are strongly dependent on the operating temperature of the Greasomatic rather than the bearing. For example, under normal working conditions using approved lubricants, the Type 3 will deliver 1.2cc daffy for 3 months at 25°C, 0.5cc daily for 7½ months at 5°C, or 2.5cc daffy for lfi months at 45°C. Changes in flow resistance of the bearing are claimed to have less effect on the discharge rate from Greasomatics than from spring energised greasers. Lubricant fillings Greasomatics are available ex-stock containing nine approved lubricants. These include multi-purpose lithium soap base greases, organic based greases for low and high temperature use, an edible grease for the food and pharmaceutical industries, and three otis.
Other lubricant fillings can be supplied. However, under the sustained pressure in the Greasomatic, some greases are prone to oil-soap separation, reducing the life of the injector. The Wymark Company, Runnings Road Industrial Estate, Cheltenham Gloucestershire, GL 51 9NQ, UK
Abrasive wear test Fulmer Research Institute, in cooperation with the Government Communication Headquarters, have developed a novel, non-destructive wear test to assess the relative abrasiveness of magnetic recording tape. The test may well find an application in other areas of wear measurement. The test rig consists of a standard tape transport and a 'dummy' head made from a polished ceramic cylinder onto which has been deposited a thin metal alloy film. The test itself involves the monitoring of the electrical resistance of the metal film when a tape is passed over its surface. An abrasive tape will reduce the thickness of the metal film and so lead to an increase in the electrical resistance. An indication of abrasiveness can be achieved within a few minutes, whereas methods involving weight loss or profile measurement take considerably longer. Close simulation of the normal recording head configuration has been achieved and the results of tests with a range of tapes have shown a close correlation between observed head life and the measured tape abrasiveness. Fulmer Research Institute Ltd, Holly Bush Hill, Stoke Poges, Slough SL2 4QD, UK
Industrial fasteners are prone to corrosion and 'freezing'in aggressive environments: they often have to be freed using an acetylene torch (left). The recently developed 'Green Bolt' (right) is made from A S T M A 193 B7 or 194-2 H steel which is phosphated and coated with stratified PTFE. Green Bolts are claimed to have salt spray corrosion protection equivalent to that o f stainless steel, while retaining the mechanical properties o f the original material. The PTFE coating is said to considerably reduce the time needed to take the fasteners apart and reassemble them Metallurgica Erbese Spa, Erba ( Como ), ltaly
Controlling bearing temperature Variation in operating speed and load conditions can cause significant dimensional changes in bearings due to thermal effects. System accuracy, essential for example in numerically controlled machine tools, may be adversely affected. The Timken Company have successfully controlled bearing temperature, in a test rig, using a two-phase lubricant mixture and evaporative cooling. Tapered roller bearings with a 70.64mm bore ran at 16200 rpm with a controlled temperature of 48-51°C (118123°F).
Dummy head for measuring abrasiveness o f tape
Freon mixed with conventional oil is used as the lubricant in the system. Freon-rich vapour, evaporated from the lubricant, carries heat away from the bearing. The vapour is condensed
Closed loop evaporative cooling with a two-phase lubricant mixture can control bearing temperature
TRIBOLOGY international June 1977
143
The soluble oils, branded Mobilmet 120, 140, 150, and 170, are nonphenolic, sodium nitrite free fluids based on solvent refined mineral oil and containing rust inhibitors and a non-phenolic biocide. They are claimed to form stable emulsions with a wide range of water qualities and to give long service life when used for recommended applications. During field trials, Mobilmet 120 was tried in the machine shop of a large electrical goods manufacturer. Microbial degradation of a variety of soluble oils, accelerated by inaccessible sumps which made regular maintenance difficult, resulted in a charge life of 2-4 weeks. Use of Mobilmet 120 has resuited in the charge life being extended to, and maintained at, 12 weeks. The manufacturers suggest that two of the fluids in the series, Mobilmet 150 and 170, may be used in operations where neat oils are more common. They recommend 150 for medium to heavy duty cutting and grinding where straight oils were used, and 170 for applications which usually involve ep oils. Neat oils
The Mobilmet 450 series consists of a range of light coloured, multi-service, non-corrosive to copper, straight oils. The range covers machining operations on most materials having Brinell hardness up to about 300. In critical opera-
Testing a crankshaft using the Vitosonics crack depth gauge. Powered by a rechargeable battery, the gauge can measure cracks up to l OOmm deep in metals o f low electrical conductivity, such as iron and steel. The single probe, suitable for most applications, has spring loaded contacts to conform to uneven or curved surfaces. Vitosonics Ltd, Marshgate Drive~ Hertford SG13 7AN, UK tions, however, on draggy, difficult-tomachine materials an active oil is recommended. The 450 series oils are also suitable as machine tool lubricants and hydraulic fluids. Leaking lubricant and hydraulic systems will not cause contamination problems or deplete the additive concentration. Five active neat oils comprise the Mobilmet 700 series. They contain sulphurised and chlorinated additives and are formulated to give multi-metal and multi-operation capability. Mobil have also announced three antimist oils: Mobilmet 826, dark coloured active oil, and Mobilmet 424 and 427 which have similar performance characteristics to the 450 series. These oils are claimed to give performance levels equal or superior to conventional oils used for the same applications, while reducing oil mist. They are said to help create a healthier working environment, to reduce plant cleaning costs, and to eliminate the need for costly ventilation units. Mobil Oil Company Ltd, Mobil House, 54/60 Victoria Street, London SWlE 6QB, UK
Filters for metalworking Particles as small as 0.1 microns can be removed from metalworking coolants using a recently announced pressure leaf filter. The system is said to be particularly useful where different specifications for filtration of rolling oils, drilling tower coolants, etc call for a flexible basic system. Durco Europe's range of pressure leaf filtration equipment can be equipped with woven wire screens and fabrics to deal with particles as small as 0.1 microns. The falters can be produced in a variety of metals, including stainless steel, titanium, and Hastalloy, according to the application. For rolling oil and coolants Durco generally offer a fdtration quality of 5-0.5 microns, although screens and fabrics to deal with particles as small as 0.1 microns are available. Durco horizontal tanks, which are recommended for metal working applications, can be cleaned without opening the tanks. The filter leaves in the tank are attached to a pneumatically driven vibrator which shakes the dry
TRIBOLOGY international June 1977
141
cake off the leaves. No filter cloth is therefore required. Systems for cold rolling mills can be fully automated. The 'brain' of the system is an automated panel which monitors feed tank levels, flow control, fdtrate particle count, etc. Since feed tank oil can contain such diverse objects as tools; bottles, etc, Durco generally use a coarse screen prior to the fluid entering the system. For cleaning and maintenance, high accessibility to the filters is possible by virtue of a wheel mounted sliding casing. All vulnerable parts (pipes, valves, etc) are connected to the nonmoving head thus eliminating the risk of breakage. Durco Europe SA, Rue Verte 216-226, Box 7, B-1030 Brussels
Continuous grease injector Self-contained greasers which supply a continuous controlled flow of lubricant are claimed to avoid both the expense of centralised systems and the spasmodic delivery characteristic of hand-held guns. The continuous low pressure helps keep bearings clean by avoiding back flow of contaminants. The range of Greasomatic injectors has recently been extended to give operating lives of up to 12 months. Six standard grease fillings and three oils are available.
Pressure leaf filer for rolling oils and metalworking coolants
adaptors are available for other locations. Low pressure operation Under normal working conditions, Greasomatics operate at low pressure. If, however, old lubricant has stiffened in a neglected bearing, pressure builds up until the obstruction is cleared. In the case of complete blockage, the pressure will build up to about 10 atm, at which level the plastic base cone few ctive ~ents
Greasomatics are disposable, self-ejecting cannisters containing 120cc of grease or oil which is discharged at a constant rate throughout its working life. The manufacturers claim that life can be predicted accurately, providing the ambient operating temperature is known. Cannisters are pressurised by an electrochemical reaction. An activating screw breaks the seal between the zinc and carbon capsules and a 30% caustic potash solution. The reaction generates hydrogen in the rubber expansion chamber, extruding the lubricant into the bearing. The lubricant outlet has a ¼in BSP male thread to fit a standard grease nipple socket:
142
onsion ~nber :trolyte on assembly :ating ring ricant 'nber
:ating ring .=ors here when leant is spent ~read . . . . . . . . v, ~l¢J
Hydrogen evolved by an electrochemical reaction pressurises the lubricant in the Greasomatic continuous injector
TRIBOLOGY international June 1977
will tear, and the ejected lubricant will indicate the failure. Discharge rates are strongly dependent on the operating temperature of the Greasomatic rather than the bearing. For example, under normal working conditions using approved lubricants, the Type 3 will deliver 1.2cc daffy for 3 months at 25°C, 0.5cc daily for 7½ months at 5°C, or 2.5cc daffy for lfi months at 45°C. Changes in flow resistance of the bearing are claimed to have less effect on the discharge rate from Greasomatics than from spring energised greasers. Lubricant fillings Greasomatics are available ex-stock containing nine approved lubricants. These include multi-purpose lithium soap base greases, organic based greases for low and high temperature use, an edible grease for the food and pharmaceutical industries, and three otis.
Other lubricant fillings can be supplied. However, under the sustained pressure in the Greasomatic, some greases are prone to oil-soap separation, reducing the life of the injector. The Wymark Company, Runnings Road Industrial Estate, Cheltenham Gloucestershire, GL 51 9NQ, UK
Abrasive wear test Fulmer Research Institute, in cooperation with the Government Communication Headquarters, have developed a novel, non-destructive wear test to assess the relative abrasiveness of magnetic recording tape. The test may well find an application in other areas of wear measurement. The test rig consists of a standard tape transport and a 'dummy' head made from a polished ceramic cylinder onto which has been deposited a thin metal alloy film. The test itself involves the monitoring of the electrical resistance of the metal film when a tape is passed over its surface. An abrasive tape will reduce the thickness of the metal film and so lead to an increase in the electrical resistance. An indication of abrasiveness can be achieved within a few minutes, whereas methods involving weight loss or profile measurement take considerably longer. Close simulation of the normal recording head configuration has been achieved and the results of tests with a range of tapes have shown a close correlation between observed head life and the measured tape abrasiveness. Fulmer Research Institute Ltd, Holly Bush Hill, Stoke Poges, Slough SL2 4QD, UK
Industrial fasteners are prone to corrosion and 'freezing'in aggressive environments: they often have to be freed using an acetylene torch (left). The recently developed 'Green Bolt' (right) is made from A S T M A 193 B7 or 194-2 H steel which is phosphated and coated with stratified PTFE. Green Bolts are claimed to have salt spray corrosion protection equivalent to that o f stainless steel, while retaining the mechanical properties o f the original material. The PTFE coating is said to considerably reduce the time needed to take the fasteners apart and reassemble them Metallurgica Erbese Spa, Erba ( Como ), ltaly
Controlling bearing temperature Variation in operating speed and load conditions can cause significant dimensional changes in bearings due to thermal effects. System accuracy, essential for example in numerically controlled machine tools, may be adversely affected. The Timken Company have successfully controlled bearing temperature, in a test rig, using a two-phase lubricant mixture and evaporative cooling. Tapered roller bearings with a 70.64mm bore ran at 16200 rpm with a controlled temperature of 48-51°C (118123°F).
Dummy head for measuring abrasiveness o f tape
Freon mixed with conventional oil is used as the lubricant in the system. Freon-rich vapour, evaporated from the lubricant, carries heat away from the bearing. The vapour is condensed
Closed loop evaporative cooling with a two-phase lubricant mixture can control bearing temperature
TRIBOLOGY international June 1977
143