Cutting a Gasket for UnionA SckT tbC good way to cut a gasket for a union is

to place the gasket material (usually sheet rubber or fiber) over one end of the union and cut it to shape with light blows from a hammer;

Fig. 222.—a gasket for a union may be cut by placing a sheet of gasket material over one end of the union and hammering with a light hammer: or the material may lie marked with a few taps and then cut with a knife, scissors, or snips.

or the material may be simply marked with a few light taps, and then cut with a sharp knife, snips, or scissors.

248. Thread Compound.—In order to insure tight joints, the threads may be coated with some sort of thread compound before they arc screwed together. Thick paint, a mixture of graphite and heavy grease, or a paste of Portland cement and linseed oil may be used for this purpose. Such material may be applied to the threads on the outside of the pipe or to the threads on the inside of the fitting. On pressure lines, a tighter joint will result if it is applied in the fitting; and on suction lines, if applied to the threads on the pipe. When applied in the fitting, however, any excess material will l>e left inside the pipe. Where this would be objectionable, as in the case of pipes for drinking water, the material should be applied to the threads on the pipe.

Fio. 223.—A street ell in combination with an ell is often used to form a sort of "universal joint" to allow slight movement of the pipes without placing undue strain on the joints.

249* Removing a Leaky Section.—It is sometimes desirable to remove a leaky section in a long run of pipe without having to unscrew several joints to get it out. In such a case the leaky piece may be sawed or otherwise cut and removed without disturbing adjacent lengths. Two shorter pieces are then cut and threaded and installed in place of the leaky section by means of a union.

238. (a) What pipe tools would you recommend for the farm shop? (b) What sizes of pipe wrenches are best? (c) How may pipe be held in an ordinary vise with the aid of a pipe wrench? (d) How may pipe be cut if a pipe cutter is not available? (e) Why arc pipe taps not ordinarily included in sets of pipe dies? (/) What is the chief advantage of a ratchet type of pipe stock?

239. (a) Under what conditions would you recommend black pipe and under what condition« would you recommend galvanized pipe? (6) How is the size of pipe measured? (c) How is the size of pipe fittings designated?

240. (a) Why are pipe threads tapered? (A) Why are bolt threads not tapered?

241. (a) What are the principal common pipe fittings and for what purposes are they used? (b) What is the difference between a coupling and a union? (c) What are the two kinds of unions available? (<d) What are the principal kinds of valves and faucets? (e) Under what conditions would a gate valve be used instead of a globe valve? (J) What particular precaution should be observed in installing a globe valve? Why?

242. Why should pipework be carefully planned before starting a job?

243. (a) Just how is a pipe cutter manipulated in cutting pipe? (6) What is the recommended tooth size for hack-saw blades for cutting pipe?

Questions

244. What methods may be used for removing the burr left on the inside of the pipe by the pipe cutter?

246. (a) How far should the pipe die be threaded onto a pipe? (6) Why should it not be threaded further? (c) Should lard oil or threading oil be used on pipe dies?

246. (a) Explain and be able to demonstrate just how to make a short nipple. (6) Why can the nipple not be held in a vise while being threaded?

247. (a) How may a gasket be easily cut to fit a union? (6) What purpose docs a gasket serve?

248. (a) What materials may be used on pipe threads to insure tight joints? (&) Should the material be applied to the threads inside the fittings or to the threads on the outside of the pipes?

249. IIow may a faulty section in & long run of pipe be removed without unscrewing several joints?

References

Boss, Dent, and White: "Mechanical Training." Radebaugh: "Repairing Farm Machinery." Tu&tison and Kranzusch: "Metalwork Essentials."

Woodworking Tools and Installation Tips

Woodworking Tools and Installation Tips

There are a lot of things that either needs to be repaired, or put together when youre a homeowner. If youre a new homeowner, and have just gotten out of apartment style living, you might want to take this list with you to the hardware store. From remolding jobs to putting together furniture you can use these 5 power tools to get your stuff together. Dont forget too that youll need a few extra tools for other jobs around the house.

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