Cleaning Systems

AICHELIN CLEANING EQUIPMENT

Flawlessly clean surfaces are the deciding factor for the quality of end-products when parts are to be heat treated.

1.Cleaning methods

Water based cleaning systems have met with general acceptance for parts cleaning before and after heat treatment. Due to reasons of environmental protection and cost, they have largely replaced the systems that work with halogenated hydrocarbons or cold cleaners(aromatic hydrocarbons). 

In hardening plants, water based cleaning has proven itself to be the best cleaning method,from both the economical as well as ecological standpoints.

2.Cleaning agents

For the most part, demulsified systems have proven themselves in practice for cleaning with aqueous cleaning methods. Only these ensure allow oil-load in the washing solution, which prevents re-greasing of the parts.

3. Cleaning plants

Based on the various requirements in relation to throughput performance, cleaning quality,flexibility, and environmental protection, AICHELIN has developed numerous cleaning units and successfully commissioned them for our customers. 

3.1 Submersion spray

 Design characteristics

• Oscillating system for dipping the charge in the cleaning bath
• Spraying system with rotating jet arms
• Vapor vent condenser (opt.)
• Re-dosing system on cleaning tank from spray tank
• Fresh water supply to spray tank
• Stainless steel design
• Oil separator for submersion bath
• Oil separator for submersion bath
• Operation produces almost no waste-water and exhaust air

These patented units are used especially where highest levels of purity are required and / or geometrically complex components are to be cleaned.

The essential components include a vacuum tight cleaning chamber, isolated tanks for two(optionally: three) cleaning agents, vacuum pump, spray pump and heating for each agent and an oil separation unit.

3.2.1 Design characteristics

• Low-pressure boiling “VACUPEARL® ” for improved cleaning effect, even in inaccessible areas.
• Vacuum drying unit for achieving completely dry components.
• Stainless steel design
• Oil separation for each cleaning agent(optional) Heater exchange without emptying the tank
• Operation produces almost no wastewater and exhaust air
• Short cycles and low energy consumption

The cleaning cycle is dependent on the type and thickness of the soiling, the cleaning agent used and the desired degree of purity. A typical process could be undertaken as follows and is freely-programmable:

After pre-spraying the charge with the first cleaning agent, the container is filled with medium 1 and subsequently the low-pressure boiling process is started. After pressure is equalized, the chamber is emptied and the charge is sprayed again. 

This cycle can be repeated with additional cleaning or rinsing fluids.

Afterwards the vacuum drying process is undertaken and the container is ventilated to remove the charge.

3.2.3 Low pressure boiling VACUPEARL

The patented Vacupearl system works by creating a vacuum above the bath level. This causes the cleaning fluid to start to boil and steam bubbles form predominately on the work piece surface of the charge.

This provides the following advantages:

• This provides the following advantages:
• Detergents are delivered directly to the work piece and do not have to be diffused by the liquid barrier.
• Steam collects predominantly where the enclosed liquid quantities are relatively small in comparison to the surrounding part surface, such as for example, in blind holes,grooves, empty spaces, or between tightly loaded parts.
• The flotation effect brought about by the addition of air is further strengthened by the expanding volume of steam.

In order to achieve a good cleaning effect, the operating temperature should generally be between 80 – 85° C. The charge will then have enough residual heat to be used to evaporate the water on the parts. Vacuum drying enable seven awkward areas, such as blind drill holes, thin lubrication holes and even suction chambers to be dried completely. Generally 0.1 – 0.3 % of the charge weight in water will stick to the work pieces. Vacuum drying allows up to 1 percent in weight of water to be dried off.

Absolutely dry components are required:

• Before vacuum heat treatments
• Before diffusion heat treatment processes
• Before low-temperature tempering processes
• Before work procedures where water residue is obstructive
• Before work procedures where water residue is obstructive

The agent tank is connected by means of cascades. The first agent tank has an overflow chamber, in which the demulsified oil-cleaner mixture flows, and is then pumped out with a separation pump to the coalescence separator