Solder Wire Presses

Solder wire consists of a tin tube of a maximum outside diameter of about 9 mm and a wall thickness of 1.5 to 2 mm, which is filled, while being extruded, with hot, liquid colophony. The wire is extruded on vertical or horizontal presses. 

The design of the tools in the base of the container is illustrated in Fig. 9. The tin is extruded vertically to the center-line of the container. 

A steam- or electrically heated pot contains the colophony which is supplied to the mandrel through a pipe. Container and tooling are heated, too, and for this purpose the jacket is provided with a number of bores 

The press is set on a base frame in a position inclined from the horizontal so as to permit the escape of air while the liquid metal is charged and to allow for impurities to rise to the surface. The colophony pot is mounted on the counterplaten. 

The general arrangement of the tools with the container and the ram for extruding solid wire is illustrated in Fig. 11. While filling the con- 

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Fig. 10 shows a solder wire press of the horizontal type. The main cylinder is connected to the counterplaten by two columns. The plunger, which is sealed by a stuffing box and packing collars, presses on a crosshead guided in its travel on the columns, and is retracted by a pullback... 

Solder wire presses are generally designed for a pressure capacity of about 250 tons and an effective charge of... 

Apart from the lead pipe press, there was also designed a series of smaller presses, the most important types of which being employed for the manufacture of curved lead pipes for use as bends or syphons, of lead wire of round or profiled cross-section, and of tin solder wire. 

Fig. 8. Vertical press for manufacture of solder wire with resin core (By Hj draulik, Duisburg)...

All SERS experiments were conducted with a polycrystalline silver working electrode prepared by press-fitting a 6 mm diameter cylinder of silver into one end of a 0.375 inch diameter Teflon rod through which a 6 nm diameter concentric hole had been drilled. Electrical contact was made via a copper wire soldered to the silver. The geometric area of the silver disk was 0.28 cm2. 

Electrical conductive-wire contacts, terminals, switch pans, bus bars Hardware cotter pins, nails, rivets, soldering copper, ball floats Other, anodes, chemical process equipment, kenles, pans, printing rolls, expansion plates, rotation bands, die-pressed forgings... 

Figure 5.1 Disassembled view of the spectroelectrochemical cell. (1) Tightening brass cap (threaded inside). (2) Brass ring required to tighten the cell. (3) Working electrode (brass rod with platinum soldered to the base). (4) Auxiliary electrode platinum wire with the tip made flush to the teflon base of the cell. (5) Pseudoreference electrode silver wire, also made flush to the teflon. (6,7) Luer-lock-type injection ports. (8) Cell body, top part aluminium, lower part teflon. (All three electrodes and both filling ports are press fitted into the cell body, so that they can be replaced if needed.) (9) Teflon spacer, determines the pathlength of the cell and masks the reference and counter electrodes from the incident beam. (10) Calcium fluoride window (Wilmad, standard 38.5 x 19.5 x 4mm). (11) Rubber gasket. (12) Hollow brass cell body with threaded inlet and outlet ports (Swagelock) for connection to circulating bath. (13) Two-mirror reflectance accessory (Thermo-SpectraTech FT-30). (14,15) Mirrors.

When you have decided what type of cell to use for your project, you can move on to purchasing the tab and bus ribbon that will connect the cells and strings of cells. Tab and bus ribbon are made from soft copper that is pressed into a flat wire. This ribbon is tin coated to make it easier to solder. Most tab and bus wire used for BSPMs is. 003",. 004", and. 005" thick. 

While keeping the blades closed part-way down into the round cut you have just made (but not pressing onto the metal very much), strongly push the tool toward the end of the wire, so the little cylinder of insulation slides entirely off the wire. The metal will now be exposed, and it is probably ready for soldering. In case, however, the metal appears black or otherwise dirty, scrape it clean with the sharp blades of the tool. (The loss of a few thin copper filaments is OK.)... 

An alternative approach to the open solder problem uses a capacitive coupling technique to look for opens. The technique exploits the fact that many ICs have a leadframe that forms the conductive path from the legs of the device to the die bond wire pads. Using the bed of nails, all but one node attached to the IC can be grounded (this is an unpowered technique) and a small AC signal can be applied to the node that remains. An insulated metal plate pressed against the top of the IC forms the top plate of a capacitor and the stimulated IC leg and lead frame conductor form the bottom plate. 

Crystalline membranes were made from the powders of Ag2S and Agl mixed in the ratio 1 1 by weight and pressed in the fly press at 150 bars for 3 h. Silver metal layer was attached to one side of the membrane and then the contact wire was soldered to this layer. Both types of membranes were moimted separately into special bodies for flow-injection setup. At least three sensors of each type were tested. The polymeric sensors were conditioned in 0.01 M solution of cyanide at least for 1 day before measurements. 

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