These are the answers to the ANSI pump quiz that was published in the September 2017 issue.
by Jim Elsey
September 12, 2017

Below are the questions with the correct answer only. If you missed the issue, take this quiz here.


1. The modern version of the ANSI B73.1 specification has its roots in the AVS (American Voluntary Standards) from the 1950s.
A) True

2. Flanges: Bolt holes may be drilled and tapped when there is inadequate space for nuts behind the flange.
A) True

3. When a heating jacket is used the steam inlet shall be:
A) On the top and the drain on the bottom

4. Impellers shall be balanced to this standard at a minimum:
B) ISO 1940-1 Grade 6.3

5. If the method of impeller attachment is threaded, the pump rotation shall have the shaft (design) function to tighten the impeller:
A) True

6. The casing drain connection shall be drilled and tapped only when specified by the purchaser. Otherwise, there will be no drain penetration. Further, the manufacturer shall always provide a casting “boss” at the lowest point on the casing to accommodate at a minimum a ½ in NPT penetration when specified.
A) True

7. Pump operating clearances shall be adequate to prevent internal rubbing when the pump is subjected to the maximum allowable flange loads (pipe strain) when operating in the allowable operating region (AOR).
A) True

8. Pump shaft “runout” on new pumps shall be no more than 0.001 inches when measuring the shaft on centers, and 0.002 inches when the shaft is installed in the pump.
A) True

9. Bearing life (L10) shall be a minimum 37,500 hours if the pump is operated in the allowable operating range.
B) False
The correct answer is 17,500 hours.

10. Standard lubrication design for the bearing frame is set for:
D) Oil bath
All other answers are optional.

11. The bearing frame shall include a drain plug that is:
D) Magnetic

12. The bearing frame when set up for oil bath lubrication shall have:
D) All of the above are true.

13. Gland bolt stud and nut materials can be made from grade B7 and 2H carbon steel.
B) False

14. The minimum casing corrosion allowance is:
D) 0.120 inches

15. The direction of rotation when viewed from the driver perspective shall always be:
A) Clockwise

16. A lifting eye is to be provided on the motor and shall be capable of lifting the entire weight of the motor, baseplate and pump.
B) False

17. The bearing frame adaptor shall:
A) Be designed to resist any amount of torque that the shaft design can handle

18. When testing the pump for noise:
D) Answers A and B above

19. Vibration limits for the pump as measured on the bearing frame must meet ANSI /HI 9.6.4 limits no matter where the pump is operated on the curve.
B) False

20. The pump allowable operating range (AOR):
F) Answers C and D above

21. With the pump operating in the AOR:
A) There is no consideration for minimum thermal flow considerations

22. Pursuant to the ANSI specification B73.1, it is perfectly acceptable for any portion of the motor to hang over the base plate on the sides and back (non-coupling end) by any amount.
B) False

23. There are circumstances where the NPSHR for the pump may be less than the NPSH3.
A) True
In these situations, it must be agreed to by the purchaser and the supplier.

24. Published performance curves shall be based on tests conducted in accordance with ANSI/HI 14.6.
A) The accuracy of the curves shall be that 90 percent of pumps purchased untested when operated between minimum flow and BEP will meet published head points within plus or minus 5 percent and efficiency within plus zero percent and minus 5 percent.

25. When NPSHR tests are required and conducted:
E) Unless otherwise agreed to by the purchaser and supplier, the test shall be a type II test, which is solely for determination of NPSH3 at the rated flow point only.

Bonus Question
For metallic pumps. All casings, seal chambers (stuffing boxes) and jackets MUST be hydrostatically tested: (This test should be a witnessed and documented test.)
D) For 10 minutes at 150 percent of the maximum design pressure for that material rating at 100 F (38 C).

Reference document: ASME /ANSI B73.1 (2012) , Specification for Horizontal End Suction Centrifugal Pumps for Chemical Process.