49 C.F.R. § 230.71 – Orifice testing of compressors. | Midpage

49 C.F.R. § 230.71

Orifice testing of compressors.

Effective Jan 1, 2017

(a) Frequency of testing. The compressor or compressors shall be tested for capacity by orifice test as often as conditions may require, but not less frequently than once every 92 service days.

(b) Orifice testing criteria.

(1) Compressors in common use, as listed in the following table, shall have orifice test criteria as follows:

Make	Compressor size	Single strokes per minute	Diameter of orifice(in inches)	Air pressure maintained(in pounds)
Westinghouse	91⁄2	120	11⁄64	60
Westinghouse	11	100	3⁄16	60
Westinghouse	150 CFM 81⁄2 CC	100	9⁄32	60
Westinghouse	120 CFM 81⁄2	100	15⁄64	60
New York	2a	120	5⁄32	60
New York	6a	100	13⁄64	60
New York	5b	100	15⁄64	60
Note: This table shall be used for altitudes to and including 1,000 feet. For altitudes over 1,000 feet the speed of compressor may be increased 5 single strokes per minute for each 1,000 feet increase in altitude.

(2) For compressors not listed in the table in paragraph (b)(1) of this section, the air pressure to be maintained shall be no less than 80 percent of the manufacturer's rated capacity for the compressor.