Brake fluids are a safety critical component for any motor vehicle and over the years, customer awareness has increased manifold regarding regular monitoring and change of the critical fluid. Given the wide variety of driving conditions and weather variations in India, it is important for an OEM to opt for a product, which not only adapts itself to different weather conditions, but also boasts longer shelf life.
S-CCI India Private Limited is the largest manufacturer of automotive coolants in India and is a key supplier to major international and domestic OEMs for functional chemicals and brake fluids. Auto Tech Review had the opportunity to visit the brake fluid division at the Bhiwadi facility of the company, in Rajasthan, to understand the role of brake fluids in vehicle safety. We met S K Singh, Director, S-CCI India Private Limited, who demystified brake fluid technology and the intricacies of manufacturing this crucial automotive ingredient.
MANUFACTURING AND STORAGE
Established in 1985, S-CCI India was established after a technical collaboration with CCI Corporation, Japan. Spread across 24,200 sq m, the Bhiwadi plant has a capacity to produce 2,500 kilolitres of brake fluid per year, while the company’s Sitarganj facility in Uttarakhand produces 2,000 kilolitres of brake fluid in a year.
Handling and transport of brake fluids can be a challenging task and S-CCI India employs the use of custom-made closed process tanks with coaxial mixing technology to store and transport these fluids, in order to avoid contamination and possible chemical reactions with the container material itself. The process control unit ensures automatic blending of materials through the use of fully integrated PLC-driven controllers.
The quality analysis and R&D department at S-CCI India has the capability to design, develop and engineer custom-built solutions for brake fluids as per international OEM specifications. A galvanostatic corrosion testing lab and a chromatographic and spectrometric analysis lab are also in place to identify long term dynamic corrosion, glassware static corrosion and heat rejection corrosion, all of which help the company create a higher quality product.
The quality of water used also plays an important role in the chemical blending process for brake fluid manufacturing. In order to demineralise water, the company has a captive de-mineralisation (DM) and reverse osmosis (RO) plant, with dedicated process lines for multiple blending requirements. Taking anti-permeability a step further, high-stability high density polyethylene (HDPE) colour bleaching composition is used. The brake fluid composition contains 12 % special additives and 3 % high-tech pigments, in order to negate any adhesive tendencies during the blending process.
S-CCI’s customers include major automotive OEMs, which adhere to strict quality standards. With constant research and development happening in the technology for brake fluids, the product life has gone up significantly in recent years. Brake fluids are required to withstand the test of time, without the need to be replaced, said Singh. To cater to the stringent norms of its customers, S-CCI India has an advanced process control lab with 100 % testing facilities as per international standards for brake fluids.
Brake fluids are classified by both ‘dry boiling point’ and ‘wet boiling point’ and are also segmented by the US Department of Transportation (DOT) rating; DOT 3, DOT 4, DOT 5, and DOT 5.1. In this, DOT 3 brake fluids have a lower boiling point and are usually glycol ether based. The brake fluid industry has determined by consensus that glycol ether fluids are the most economical way to meet requirements and their viscosity is instrumental in defining the functioning of advanced safety systems like ABS and EBD, which are currently in the process of being mandated across most vehicle segments. Correct brake fluid viscosity is an important factor for proper operation of ABS and active handling control systems on modern vehicles.
MOVE TO HIGHER SPECS
Some carmakers like Ford and Nissan have already changed to DOT 4 specific brake fluids, whereas companies like Maruti Suzuki, Toyota and Honda Cars use DOT 3 specific brake fluids of a very high order, bordering on DOT 4, Singh said. Earlier in India, windshield washer fluids were also not commonly used, but due to their anti-clogging property, global car makers are now providing them across their product portfolio. While not all OEMs have adopted this product, most of them have it available at their dealerships.
Hydraulic brake fluids operate on the principle of Pascal’s law, whereby pressure exerted on a liquid will be transferred equally in all directions. The operating mechanism involves the actuation of brakes via the brake pedal, which causes pressure to develop in the master cylinder. This pressure is transmitted in all directions equally through brake fluid pipes, and then reaches the slave cylinders, causing the pistons to operate. The piston in turn, exerts pressure on brake pads and shoes in disc and drum braking mechanisms, thereby bringing the vehicle to a halt.
Highlighting the importance of an efficient brake fluid, Singh said that as cars are becoming faster, braking performance needs to match up. This warrants the use of brake fluids with a higher equilibrium reflux boiling point (ERPB), which are now entering the market, along with a few synthetic brake fluids. Proper rubber swelling properties are a must for brake fluids to prevent leakage and/or damage to seals.
The brake fluid causes the rubber cup with the braking system to swell or contract, depending upon the force with which the brakes are applied. A wrong choice of brake fluid would result in the rubber cup either expanding too much or not expanding enough; either of which will result in poor final braking performance – a situation that must be avoided at all cost.
Ideally, a quality brake fluid should have a high boiling point and high-temperature stability to absorb and withstand the heat generated during braking. It must not form sediments and should not deteriorate or oxidise even when used for prolonged durations, at high temperatures.
Anti-corrosion properties are also a must to prevent the corrosion of zinc, tined-iron, steel, aluminium, cast aluminium, brass and copper parts, which the braking system is composed of. During rigorous usage at varying temperatures, brake fluids must maintain an appropriate viscosity, while ensuring proper braking function to prevent brake fluid leakage at high temperatures, and ensure smooth function of the brake system at low temperatures.
Water tolerance is another important characteristic, which an ideal brake fluid must have. The fluid must not turn turbid, separate or solidify at both high and low temperatures, even when moisture is absorbed, to minimise boiling point lowering by moisture absorption, to prevent vapour locking under severe conditions.
The manufacturing process of brake fluids requires regular checks to eliminate contamination during all stages. Also, a lower content of anti-corrosion additives is detrimental to the life span of a brake fluid and a manufacturer must ensure that these additives do not corrode with regular application. This requires rigorous pressure and temperature monitoring, which, Singh said was becoming increasingly difficult in the highly polluted locales of Bhiwadi. Methods of insulation have to be revamped every year, while OEMs conduct regular quality checks for approving product standards.
A key safety aspect which car owners need to be aware of is the need to use a brake fluid recommended by OEMs. Often, customers blame the engine oil during an engine seizure, but the real cause might be overheating due to the wrong coolant choice. Singh said that it is heartening to see customers waking up to these intricacies of engine management today, which would go a long way in ensuring a longer engine life and reduce fatalities on road.
Overall, given their market growth and expansion in India, S-CCI is aiming to take its success story to global markets as well in the near future.
TEXT: Anwesh Koley
PHOTO: S-CCI India