What is "sucker rod"

Sucker \Suck"er\ (s[u^]k"[~e]r), n.

1. One who, or that which, sucks; esp., one of the organs by which certain animals, as the octopus and remora, adhere to other bodies.

2. A suckling; a sucking animal.
   --Beau. & Fl.

3. The embolus, or bucket, of a pump; also, the valve of a pump basket.
   --Boyle.

4. A pipe through which anything is drawn.

5. A small piece of leather, usually round, having a string attached to the center, which, when saturated with water and pressed upon a stone or other body having a smooth surface, adheres, by reason of the atmospheric pressure, with such force as to enable a considerable weight to be thus lifted by the string; -- used by children as a plaything.

6. (Bot.) A shoot from the roots or lower part of the stem of a plant; -- so called, perhaps, from diverting nourishment from the body of the plant.

7. (Zo["o]l.)

   1. Any one of numerous species of North American fresh-water cyprinoid fishes of the family Catostomid[ae]; so called because the lips are protrusile. The flesh is coarse, and they are of little value as food. The most common species of the Eastern United States are the northern sucker ( Catostomus Commersoni), the white sucker ( C. teres), the hog sucker ( C. nigricans), and the chub, or sweet sucker ( Erimyzon sucetta). Some of the large Western species are called buffalo fish, red horse, black horse, and suckerel.

   2. The remora.

   3. The lumpfish.

   4. The hagfish, or myxine.

   5. A California food fish ( Menticirrus undulatus) closely allied to the kingfish (a); -- called also bagre.

8. A parasite; a sponger. See def. 6, above.

   They who constantly converse with men far above their estates shall reap shame and loss thereby; if thou payest nothing, they will count thee a sucker, no branch.
   --Fuller.

9. A hard drinker; a soaker. [Slang]

10. A greenhorn; someone easily cheated, gulled, or deceived.

11. A nickname applied to a native of Illinois. [U. S.]

12. A person strongly attracted to something; -- usually used with for; as, he's a sucker for tall blondes.

    11. Any thing or person; -- usually implying annoyance or dislike; as, I went to change the blade and cut my finger on the sucker. [Slang]

    Carp sucker, Cherry sucker, etc. See under Carp, Cherry, etc.

    Sucker fish. See Sucking fish, under Sucking.

    Sucker rod, a pump rod. See under Pump.

    Sucker tube (Zo["o]l.), one of the external ambulacral tubes of an echinoderm, -- usually terminated by a sucker and used for locomotion. Called also sucker foot. See Spatangoid.

A sucker rod is a steel rod, typically between 25 and 30 feet (7 to 9 meters) in length, and threaded at both ends, used in the oil industry to join together the surface and downhole components of a reciprocating piston pump installed in an oil well. The pumpjack is the visible above-ground drive for the well pump, and is connected to the downhole pump at the bottom of the well by a series of interconnected sucker rods. Sucker rods are also commonly available made of fiberglass in 37 1/2 foot lengths and diameters of 3/4, 7/8, 1, and 1 1/4 inch. These are terminated in metallic threaded ends, female at one end and male at the other.

Working The surface unit transfers energy for pumping the well from prime-mover to sucker rod string. In doing this, it must change the rotary motion of prime-mover to reciprocating motion of sucker rod. And it must reduce the speed of prime-mover to suitable pumping speed. Speed reduction is accomplished at gear reducer. And rotary motion of crank shaft is converted to oscillatory motion by means of walking beam. The crank arm is connected to the walking beam by means of pitman arm. Walking beam is supported by Samson post and saddle bearing. The horse head and bridle are used to ensure that pull on the sucker rod string is vertical all times so that no bearing movement is applied to that part of sucker rod string above stuffing box. The polished rod and stuffing box combination is used to maintain a good liquid seal at the surface.