US2289405A - Method for reconditioning hot oil pump blocks - Google Patents

Description

C. C. BEAL July 14, 1942.

Filed Nov. 21, 1939 METHOD FOR RECONDITIONING HOT OIL PUMP BLOCKS Fla-3 C. CiqBl-ZAL 1 v R- ,SW BY aim SK /m HIS ATTORNEYS TOR Patented July 14, 1942 METHOD FOR RECONDITIGNING HOT OIL PUMP BLOCKS Charles C. Beal, Port Arthur, Tex., assignor, by mesne assignments, to The Texas Company, New York, N. Y., a corporation of Delaware Application November 21, 1939, Serial No. 305,465

1 Claim.

This invention relates to a method for reconditioning or reclaiming condemned liquid ends or blocks of hot oil pumps.

In oil refineries and other places where oils are treated and handled it is frequently necessary to transport such oils from one point to another, and the usual practice is to convey the oils through pipe lines by means of pumps. When it becomes necessary to convey the oils while in a heated condition, pumps of a special design are ordinarily employed. These special pumps are what are commonly referred to as hot oil pumps, and they are designed to withstand the high temperatures, and frequently high pressures, of the oils handled by them. However, after long and generally continuous operation these hot oil pumps are aifected by the corrosive action of the heated oils and the walls of the various openings and ports become so badly corroded that the efficient operation of the pumps is impaired, corrosion taking place particularly between the valve ports and in the suction and discharge channels. When this condition occurs, the usual refinery practice is to discard the damaged pump blocks and replace them with new blocks, but obviously this is a costly procedure.

It is an object of the present invention to provide a method for reconditioning or reclaiming the blocks of hot oil pumps which have been rendered useless or practically so by the corrosive action of the hot oils handled by them. More specifically, it is an object of this invention to provide a method for reconditioning the various openings and ports of badly worn hot oil pump blocks to restore them to their original state of efliciency. Still more specifically, the invention has for an object to provide a method for removing the corroded and pitted metal from the walls of the openings and ports of hot oil pump blocks, and then lining the various openings with a corrosion resistant metal and machining the lined ports and passageways to restore them to their original sizes.

Additional objects, features and advantages of the present invention will appear from the folchined to size and with a lining of corrosion resistant metal.

In Fig. 1 of the drawing there is shown a typical hot oil pump block I, preferably-formed I I2 and II, respectively, is interconnected with cross ports I6 of various sizes, while a plurality of valve ports l8 rise vertically to the upper surface of the block to. Small holes or conduits 20, 20, each communicating at one end with the lower opening l2, are drilled through the botlowing description when taken in connection 5 of Fig. 1 showing the openings and ports of the block machined to over-size and completely filled with corrosion resistant metal; and

Fig. 3 is a sectional view taken on the line 3-3 tom of the block l0 near the opposite ends thereof.

The preparation of a block such as that described above for reconditioning includes the sand blasting and cleaning of all surfaces which are to be lined, and all the openings and ports which are to be reconditioned are over-size ma.- chined in order to assure minimum liner thickness. After the machining of the openings and ports to over-size has been completed, it is generally desirable to core (not shown) these openings with extra heavy pipe tofacilitate machining and save metal. The coring may be accomplished in any suitable manner.

Prior to pouring the corrosion resistant metal, which is preferably an alloy steel containing as alloying constituents 4-6% chromium and 50% molybdenum, the entire block is heated to a temperature of approximately 1300 F. The block may be rammed up with sand to hold the temperature and insure safety until it is ready for pouring. The molten metal, when ready for pouring, has a temperature of approximately 2900 F. and the pouring is done before the block loses its red heat. The center or largest vertical opening [8, which is connected to all ports,

may be conveniently used as a pour basin, as

through it access can be had most easily to all of the other openings and ports.

After all of the openings and ports have been completely filled with the corrosion resistant metal the block is allowed to cool, after which all excess metal is burned off and the entire block is then annealed in an annealing oven and upon completion of the annealing operation the cyl- 5 inder or block is completely machined, the various ports and openings being bored to the desired size. The outer contacts of the chromium steel to the carbon steel block, and any defects found upon machining, are welded, after which of Fig. 1 showing the openings and ports mathe entire block is re-annealed. After the foundry and machine work is otherwise completed the block I! may be turned upside down and iron cement poured into one of the holes 20. The cement is allowed to fill up any of the voids then remaining in the block due to shrinkage. Pouring of the iron cement is preferably continued until it has filled all of the voids and begins to run out the opposite end of the .block. As a result of the reconditioning of hot oil pump blocks in the manrer herein described the reclaimed blocks are again ready for service, and experience to date indicates that blocks reclaimed in this manner will have a life exceeding that of the original factory blocks of forged steel.

As illustrative of one corrosion resistant metal which has been found to be satisfactory for reconditioning pump blocks in the manner herein described, a typical analysis range is given below:

Carbon 0.15-0.20 Silicon 0.30-0.45 Manganese 0.40-0.60 Chromium 4.00-6.00 Molybdenum 0.50-0.60

It will be readily appreciated from the foregoing that while the invention has been described as applicable particularly to the reconditioning or reclaiming of a particular type of hot oil pump block, it is equally applicable to the reconditioning or reclaiming of other types of hot oil pump blocks or various types of equipment, such as pumps, motor cylinder blocks and the like.

Obviously many modifications and variations of the invention, as hereinbefore set forth, may be made without departing from the spirit and scope thereof, and therefore only such limitations should be imposed as are indicated in the appended claim.

I claim:

The method of reconditioning a worn hot oil pump block having openings and ports therein, which comprises machining said openings and ports to over-size, filling said openings and ports with molten corrosion resistant metal to form a substantially solid block, rough machining new openings and ports through the corrosion resistant metal, welding the metals at all surface points, annealing the .block for stress relief, and machine finishing the openings and ports to substantially the original sizes.

CHARLES C. BEAL.

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