How To Set Up a Business Unit for Crimped-Wire Connector Manufacturing

This project report is focussed on setting up a production unit for crimped-wire connectors.

Electronic product packaging has evolved a lot to support the increasing demand for products with complex modular forms of construction. Complex construction needs a wide variety of connectors for inter-connection of different functional units within an electronics equipment/system. Thus, connectors have been gaining importance as a component with advancements in electronic equipment.

Majority of connectors used nowadays has an insertable or removable contact. These are assembled with wires, cables and harnesses, and then inserted into dielectric housing. Crimped-wire connectors are solderless in nature. These are typically used to terminate stranded wires.

There are different types of crimp connectors. But, the most common ones are barrel and open barrel. With barrel-type connectors, a stranded wire is inserted into the cylindrical metal opening (hence, barrel) and then crimped. This is perhaps the most common type of connector.

An open barrel connector is also aptly named, as the barrel is spread open into V or U shape. A wire is cradled into the connector before it is crimped close. Since the wire can be laid into the connector—as opposed to being threaded into it as with a barrel connector—this type of connector is easier to use in automated applications. Connections are generally stronger than those created by barrel connectors. The strength and ease of use make this type of connector common for automotive and industrial uses.

There is much debate over the advantages and disadvantages of crimped and soldered connections. The connection that makes the most sense depends heavily on specific size and type of wire as well as application.

Crimped-wire connectors are mainly used for the interconnection of printed circuit boards (PCBs). Considering huge domestic and export demand, such connectors with good quality and competitive prices have enough market potential.

Manufacturing process

The manufacturing process starts with stamping the crimp from the plated sheet of brass or phosphor bronze using high-speed and high-accuracy stamping press. This involves crimping of the wire terminal. The compressed joint is called a crimp joint, which is made using hand tools or semi-automatic crimping machines.

Crimped terminals are inserted into moulded housing cavities with the help of contact insertions and removal tools. Then, complete crimped connectors are checked as per predefined standards and specifications.

The entire crimping process can be described step by step as follows (Fig. 1):

1. Check if tooling is clean and not worn out. If necessary, clean and replace damaged/worn out tooling.
2. Disconnect power to the press and remove guarding devices.
3. Install appropriate tooling into the press.
4. Load terminals into the tooling, so that the first terminal is located over the anvil.
5. Manually cycle the press to ensure a complete cycle without interference. If it cannot, remove tooling and check press shut height. Go to step 3.
6. Check if the tooling is aligned. Check the impression on the bottom of the crimp made by anvil tooling. Make sure extrusions and crimp forms are centred. If not, align tooling and go to step 5.
7. Check whether the terminal feed locates the next terminal over the centre of anvil tooling. If not, adjust terminal feed and feed finger, and go to step 5.
8. Re-install all safety devices that were removed during setup. (Follow all safety requirements listed in individual press and/or tooling manuals.)
9. Crimp sample terminals under power.
10. Evaluate cut-off tab length and conductor bell mouth. If adjustment is necessary, disconnect power to the press and remove guarding. Adjust track position. Manually cycle the press and check the feed finger for feed location. Go to step 7.
11. Evaluate conductor brush. If adjustment is necessary, disconnect power to the press and remove guarding. Adjust wire stop for bench applications, or press position on automatic wire-processing equipment. Go to step 8.
12. Evaluate insulation position. If necessary, adjust strip length, crimp new samples and go to step 11.
13. Loosen insulation crimp height.
14. Crimp sample terminals.
15. Measure conductor crimp height and compare with specifications. If necessary, disconnect power and remove guarding. Adjust conductor crimp height, install guards, connect power and go to step 14.
16. Perform pull force test. If it fails, refer to troubleshooting.
17. Adjust insulation crimp.
18. Crimp sample terminals.
19. Evaluate insulation crimp. If necessary, disconnect power and remove guarding. Adjust insulation crimp height, install guards, connect power and go to step 18.
20. Measure crimp height and compare with specifications. If necessary, disconnect power and remove guarding. Adjust conductor crimp height, install guards, connect power and go to step 18.

Good manufacturing practices

Pollution control

The government places utmost importance on controlling environmental pollution. Therefore small-scale entrepreneurs need to follow environmental-friendly practices and adopt pollution-control measures by process modification and technology substitution.

India acceded to Montreal Protocol in September 1992. Hence, production and use of ozone-depleting substances like chlorofluoro carbon (CFC), carbon tetrachloride, halons and methyl chloroform need to be phased out immediately with alternative chemicals/solvents. A notification regarding detailed rules to regulate ozone-depleting substances phase-out under Environment Protection Act, 1986 was put in place with effect from July 19, 2000.

Energy conservation

With growing energy needs and shortages coupled with rising energy costs, a greater thrust in energy efficiency in the industrial sector is being given by the government of India since 1980s. Energy Conservation Act, 2001 was enacted on August 18, 2001, which provides for efficient use of energy, its conservation and capacity building. The following steps may help with the conservation of electrical energy:

1. Adoption of energy-conserving technologies, production aids and testing facilities
2. Efficient management of process/manufacturing machineries and systems, QC and testing equipment for yielding maximum energy conservation
3. Optimum use of electrical energy for heating during soldering process can be obtained by using efficient temperature-controlled soldering and de-soldering stations
4. Periodical maintenance of motors, compressors and the like
5. Use of power-factor correction capacitors, proper selection and layout of lighting systems, timely switching on/off of lights, use of compact fluorescent lamps, wherever possible, and so on

Raw materials and equipment

Basic raw materials needed for a crimped-wire connector are listed below.

1. Plastic parts
2. Plastic moulding powder
3. Brass, phosphorus, bronze strips
4. PVC wires
5. Consumables and packaging material

You must procure some basic machinery and equipment for this business. These are given below.

Machinery and equipment

These include:

1. Vertical injection-moulding machine
2. Air wire stripper
3. Wire-twisting machine
4. Wire-stripping machine
5. Soldering machine (semi-automatic)
6. Applicator
7. Air press
8. Terminating machine
9. Precision punch

Testing equipment

These include:

1. Milli-ohm meter
2. Insulation tester
3. High-voltage breakdown tester
4. Insertions and withdrawal force tester
5. Testing gauge for crimp system

In addition, arrange utilities like water and electricity. Further, a medium- and large-scale unit needs 300sqm area for its operation.

Business economics

An indicative analysis has been given on the following basis and presumptions:

1. Basis for calculation of production capacity is taken on a single shift of eight hours per day basis on 75 per cent efficiency.
2. Maximum capacity utilisation on single-shift basis for 300 days a year is considered. During the first and second years of operations, capacity utilisation is 60 and 80 per cent, respectively. The unit is expected to achieve full capacity utilisation from third year onwards.
3. Salaries and wages, cost of raw materials, utilities, civil construction, etc are based on prevailing rates in and around north India. These cost factors are likely to vary with time and location.
4. Interest on term loan and working capital loans are taken at the rate of 16 per cent on an average. This rate may vary depending upon the policy of the financial institution/agency from time to time.
5. Cost of machinery and equipment refer to a particular make/model. Prices are approximate.
6. Break-even point percentage indicated is of full capacity utilisation.
7. Project preparation cost, whenever required, can be considered under pre-operative expenses.
8. Essential production machinery and test equipment required for the project are indicated. The unit may also utilise common test facilities available at Electronics Test and Development Centres (ETDCs) and Electronic Regional Test Laboratories (ERTLs) set up by state governments and STQC, Directorate of Department of Information Technology, Ministry of Communication and Information Technology, to manufacture products conforming to Bureau of Indian Standards (BIS).

Financial analysis

Table I shows fixed capital, that is, land and building, and machinery and equipment. Table II shows the cost of working capital per month.

Total capital investment is given in Table III. Cost of production per annum is shown in Table IV. Turn over per annum is shown in Table V.

Profit before taxes = Turnover per annum – Cost of production per annum
= 10,000,000 – 7,601,790
= ₹ 2,398,210