We offer a wide range of Solventless Polyester Varnish (SI 901, Class 'H' semi-rigid) that has been appreciated for its high thermal capability, electric properties and excellent moisture resistance. We have designed these solventless polyester varnish in such a manner that it retains good bond strength and flexibility for resistance to thermal shock.

Production Areas:

• Impregnation of Stators and Rotors of Traction Motors, Centrifugal Motors
• Coil Impregnation of Transformers & Rotating Machine
• Impregnation of Ships & Marine Drives
• General purpose impregnating application

Salient Features:

• Excellent dielectric properties
• Excellent moisture resistance
• High flash point and negligible losses during application
• High physical strength-retains good bond strength after prolonged service at high temperature
• High overload resistance and tracking resistance
• Low toxicity compared to other Insulating Varnishes

Application Methods:

• Vacuum Impregnation
• Dip & Bake

Physical Properties:

• Viscosity at 25°C : 1000±200cps
• Density at 25°C (average) : 1.07 ±0.01 gms/ml
• Gel time (With 1% SI-001 B) at 1180C : 13 26 Minutes
• Flash Point (Pensky ¿ martens) : 420 C (108 OF)

Cured Film Property:

• Curing Schedule - Cure at 150°C - C-160°C for 4 to 6 hours after the part has reached the temperature

Application Procedure:

• Preheat part to 100-1 20°C for 1 -2 hrs. Cool to 45-60°C
• Place in vacuum tank. Apply a vacuum of 28"-30" of mercury hold for 20-30 min. Admit catalysed varnish to cover the part
• Break-vacuum with nitrogen to 20" Hg. Continue break with air. Apply pressure (50-60 psi)
• Hold for 30-60 min
• Return varnish to storage tank. Release pressure. Allow part to drain
• Cure 4-6 hours at 150 ^C - 160 ^C (after part has reached temperature)

Dip and Bake Process:

• Preheat part to 1000C - 1 20 °C. Cool it to 45-60 0C
• Dip into catalysed varnish
• Immersion time will vary approximately to 1 to 3 minutes (until bubbling of escaping air ceases)
• Drain the part for 5-10 minutes
• Cure for 4-6 hours at 150 °C - 160 °C

Storage Life:

• SI-901 varnish has shelf life of 6 months when stored at 25 ^C

We offer a wide variety of Solvent Varnishes (SI-7702) that is used for general purposes. It is curable solvent bearing and modified form of Iso Polyester. Manufactured with latest technology, the varnish has been appreciated all over the country for its excellent toughness, adhesion and bond strength. Further, our solvent varnishes are also compatible with most types of insulation systems.

Application Areas

• Transforms
• Armature and stator windings
• Coils

Salient Features

• Modified Isopolyester for continuous working at the class F temperature.
• Good tank stability
• Excellent flexibility, toughness and electrical properties
• Conforms to Is 10026 (Pt. Ill/Sec.6) 1983
• Compatible with most other insulating materials
• Very good alkali and chemical resistance
• VPI
• Hot and cold dipping
• Brushing and dipping
• Roller coating

Recommended Thinner: Xylene

Physical Properties:

• Viscosity at 250C : 350 ± 0.15 cps
• Density at 250C : 0.96 ± 0.015 gm/cc
• Drying time at 100°C thin films min. approx. : 30-40 Minutes
• Colour : Pale brown liquid

We offer a semi-flexible, 100% solids and Unsaturated Polyester Insulating Varnish (SI-902) that has high thermal capability, electric properties, tank stability and moisture resistant quality. It consists of a premeasured quantity of 702 B catalysts; the products have been designed specifically for the impregnation of DC traction motors by vacuum impregnation.

Application Areas:

• Generators and Motors (Traction)
• D.C. Mill Motors
• High Torque D.C. Motors (used in Cranes, Hoists, Mining and Earth Moving Machinery )

Salient Features:

• Solventless polyester varnish, thermal class 180 °C
• Cured Film retains flexibility and hence resists failure due to severe thermal cycling.
• Excellent Anti-track properties and moisture resistance
• Negligible losses during VPI processing
• Provides good film build
• Low toxity compared to other insulating varnishes

Application Methods:

• Vacuum Impregnation Method (VPI) is suggested
• Dipping is also applied

Physical Properties:

• Viscosity at 250C 800 ± 200 cps
• Density at 250C 1.06 ± 0.02 gm/cc (8.85 ±.15 Ib/usg)
• Geltime-1%at1180C 14-25 Minutes
• Flash Point (Pensky - martens ) 43 0C (110 OF)
• Percent solids (by weight) 100

Cured Film Properties:

Other Properties

Moisture Resistance, U Bar, 500 V

• 5hrs. (meg ohms) 105
• 24hrs.(meg ohms) 100

Cured Film Properties:

• Curing Schedule: Bale at 175 OC for 6 to 8 hours.
• Oil Resistance: one week at 180 °C-No attack

Application Procedure:

• SI-902 varnish must be thoroughly blended with 702 B catalysts before use
• Catalyst 702 B is a pale yellow to white, granular, low melting (380C) solid
• The proper premature quantity of 702 B (1 % by weight) is to be added to 702 A varnish
• Catalysed varnish can be applied by hot and cold dipping
• Suitable particularly for VPI or Roll applications

Suggested Vacuum / Pressure Cycle:

• Pre-heat part to be treated to 45-60C
• Place in vacuum tank.
• Draw vacuum of 28"-30" of mercury.
• Admit varnish to covern part.
• Partially break vacuum to 15"-20" of vacuum witrunert gas (Nitrogen or Carbon Dioxide)
• Continue to break vacuum with air (or inert gas) and apply pressure with air (50-90 psi)
• Hold Pressure for 20-30 minutes.
• Return varnish to storage tank and release pressure.
• Drain 5-15 minutes.
• Cure 6-10 hours (at temperature) at 175-185C

To obtain faster impregnation and low surface builds, the viscosity can be reduced to approximately 500 cps with 775 which is generally supplied in a viscosity range of 800 ± 200 cps

Storage Life:

• Storage life of 702 A varnish (unanalyzed) is six months at 20uC or colder
• Catalyzed tank life of 702 can be extended by proper monitoring of the gel time

Our company has specialized in the sphere of manufacturing a wide range of Liquid Polyester Varnish (SI 907 insulating varnish). It is widely used to cure a tough, rigid infusible solid. Suitable for trickle impregnation applications, our liquid polyester varnish has been acclaimed for its heat resistance, high bond strength and excellent electrical properties.  

Further, SI 907 is supplied as two component system-SI 907 A varnish and SI 907 B catalyst.

Application Areas:

• Impregnation of very high speed rotating armatures, power tools and automatic generators
• Transfer coil and capacitor impregnation

Salient Features:

• Solventless varnish, temperature class 1800C
• Cures fast and gives a tough, rigid mass having excellent mechanical and electrical properties most suitable for trickle impregnation
• Excellent bond strength at elevated temperatures - ideal for very high speed rotating armature, power tools and automotive generators
• Excellent electrical properties over a wide range of temperature
• Compatible with practically all materials in electrical equipment

Application Methods:

• Trickle Impregnation
• Dipping
• Automotive conveyorized roll through
• Vacuum pressure impregnation

Physical Properties:

• Viscosity at 25°C 750 ± 250 cps
• Density at 25°C 1.08 ± 0.01 gms/ml
• Gel time 100 0C(l% SI 907 B catalyst) 12- 17 Minutes
• Colour Mild
• For Trickle impregnation application
• Viscosity at 25 0C 310 ± 100 cps
• Get Time at 100 °c (1 % SI 907 B catalyst) 7-12 minutes

Application Procedure:

• HOT DIP - Coils stators, rotors - objects to be treated should be preheated to 100 ° - 150°c (Preheat temperature will vary inversely with the mass to be treated).
• The unit is than dipped into the catalyzed SI 907 varnish immersion time will vary from approximately 0.5-3 minutes or until bubbling of escaping air ceases.
• The unit may then be baked for 1 -2 hours at 150 ° -160°C

Automatic Conveyorized Roll through Process:

• Fill SI 907 A varnish in the dip tank
• The part should rotate at a speed of 0.75 to 1.5 rpm and undergo at least 1 revolution in the dip tank
• Cure 15 minutes to 2 hours at 150°- 160°C(302°F-320°F) depending on weight
• When processing armatures would with polyester enamelled wire, longer cure cycles or higher final baking temperature at 220 C (428 F) are suggested to develop optimum cure

Vacuum and Pressure Process:

• Coils, transformers, capacitors - place articles in a vacuum autoclave and apply vacuum, Hold for 5 to 10 minutes at minimum pressure
• Admit catalyzed varnish until parts are completely submerged
• Then break vacuum and apply pressure using inert gas such as nitrogen and carbon dioxide ) of 15 to 20 psi
• Maintain pressure for 20 to 30 minutes ¿ release to atmospheric pressure
• Remove articles from SI 907 Varnish allow to drain for 5 to 10 minutes and bake 2 hours at 80 0c (176 °F) followed by 2 hours at 125 °C (257UF)

We have developed an assortment of Thermal Endurance Varnish (SI-911) that has high thermal endurance, optimum electrical properties and excellent moisture resistance. The varnish has excellent chemical properties such as viscosity, density and flash time. Thermal Endurance Varnish is widely used in High performance Dry-Type Transformer Coil impregnation and General purpose impregnating applications.

 Application Areas:

• Impregnation of Coils & Armatures
• Impregnation of Motors
• High performance Dry-Type Transformer Coil impregnation.
• General purpose impregnating applications.

Salient Features

• Solventless polyester varnish, thermal class 220 °C
• Excellent Electrical properties.
• High flash point.
• Excellent catalyzed tank stability.
• Good bond strength white retaining a degree of flexibility
• Compatible with most insulating materials.

Application Methods:

• Vacuum Pressure impregnation
• Dip & Bake

Physical Properties:

• Viscosity at 25°C : 800 ± 200 cps
• Density at 25°C : 1.18 ± 0.02 gms/ml
• Gel time at 1180C : 15-25 Minutes
• Flash Point (Pensky - martens closed cup) : 93°C

Cured Film Properties:

Curing Schedule -2-3 hours at 160°C or 4-6 hours at 150°C or 6-8 hours at 135°C

Application Procedure:

• Preheat part to 100-100°C for 1 -2 hrs. Cool to 45-600C
• Place in vacuum tank. Apply a vacuum of 28"-30" of Hg. hold 20-30 min. Admit catalysed varnish to cover the part.
• Break-vacuum with nitrogen to 20" Hg. Continue break with air. Apply pressure (50-60 psi)
• Hold for 30-60 min
• Return varnish to storage tank. Release pressure. Allow part to drain.
• Cure 4-6 hours at 150 °C - 160 °C (after part has reached temperature)

Storage Life:

SI-901 varnish has self-life of 6 months when stored at 25 °C

We are engaged in manufacturing and supplying a wide array of Moisture Resistant Varnish (Safe Putty P-325). These are provide with three components that are to be mixed at the time of applications and applied by knife or spatula. These moisture resistant varnishes are widely used for Sealing the ends of open margins of magnet and transformer coils and Filling voids and spaces in traction motors and generators.

Application Areas:

• Filling voids and spaces in traction motors and generators
• Sealing the ends of open margins of magnet and transformer coils
• Filling voids and spaces in AC/DC rotating equipment and other electrical equipment
• General purpose high heat conducting sealant

 Salient Features:

• Thermosetting putty: Cures to a tough, rigid, heat conducting infusible solid which bonds well to most surfaces

• Very low shrinkage and high resistance to cracking

• Uses solventless varnish: Void free sealant of pores and spaces protects against oil, dirt, moisture

• High bond strength: Provides excellent mechanical strength at elevated temperatures.
• Excellent Electrical Properties
• Improved resistance to a high moisture environment

 Applications:

Fixing:

• When making P-325, Safe Putty, the entire contents of the two-compartment container must be thoroughly mixed
• Do not apply heat to the can while or after mixing otherwise jollification will occur

Storage:

• The mixed putty has a storage life of 3-4 days at 250C refrigerated at 50C it will remain usable for several weeks
• Care should also be taken not ^.contaminate the putty with foreign materials
  

Use:

• P-325, Safe Putty, may apply with a conventional putty knife or pressure gun
• The putty will not flow either hot or cold and hence, should be pressed into deep sections to insure solid filling
• Al though P-325 bonds well to most surface
• The surface should be free of oil or grease to obtain the most effective bonding