1020.5 Corrugated Metal Pipe (CMP) Inspection Guide

Metal pipe is inspected for quality and workmanship. Deviations from MoDOT specifications can keep a supplier from supplying material to MoDOT.

This guide assists in the inspection of all types and configurations of corrugated metal pipe, couplings and ends. Answer each question and take the action indicated for the answer given. If no condition is provided for a particular answer, move to the next question.

The inspector is responsible to confirm that this inspection guide is in accordance with current specifications.

Every lot should be visually inspected. The lot that appears to have the most defects, or a lot selected at random if all lots appear to be of equal quality, shall be inspected in greater detail to generally establish the Quality Control practices of the manufacturer. And at least one pipe per size offered in the lot shall be inspected in detail using this inspection guide. A lot shall be considered that quantity of material offered for inspection at one time that is of the same thickness and bears the same heat number and coating lot designation.

If this inspection guide is used to inspect a rejected pipe, it shall be submitted with the notification to the manufacturer of the failure to meet specification.

Has any of the material or pipe included in this lot been rejected during a previous inspection visit? If Yes, the entire lot is unacceptable.	Yes	No
Is this manufacturer approved for production of this type of pipe? (Refer to Qualified Brands and Manufacturers of Galvanized (Zinc-Coated) Steel Sheet or Qualified Brands and Manufacturers of Aluminum Coated Steel Sheet.) If No, stop, the pipe is unacceptable.	Yes	No
Is the pipe accompanied by a bill of lading or delivery receipt at this location? If No, stop, the pipe is unacceptable.	Yes	No
Does the bill of lading or delivery receipt contain an itemized list of the sizes and lengths of pipe? If No, stop, the pipe is unacceptable.	Yes	No
Does the bill of lading or delivery receipt contain a MoDOT sample ID or is it accompanied by a Material Shipping Report Form? If No, stop, the pipe is unacceptable.	Yes	No
Does the bill of lading or delivery receipt contain the certified statement, in.This certifies that the pipe, bands, and end sections in this shipment are in accordance with MoDOT specifications and were fabricated at an approved plant. in. If No, stop, the pipe is unacceptable.	Yes	No
Is the certified statement signed by an authorized representative of the manufacturer? If No, stop, the pipe is unacceptable.	Yes	No
Is the pipe marked (in accordance with the specification) with the sheet manufacturer’s name, tradename, or trademark? If No, stop, the pipe is unacceptable.	Yes	No
Is the pipe marked (in accordance with the specification) with the brand name? If No, stop, the pipe is unacceptable.	Yes	No
Is the pipe marked (in accordance with the specification) with the type of coating or AASHTO designation number of the coated steel? If No, stop, the pipe is unacceptable.	Yes	No
Is the pipe marked (in accordance with the specification) with the specified sheet thickness? If No, stop, the pipe is unacceptable.	Yes	No
Is the pipe marked (in accordance with the specification) with the specified weight (mass) of coating? If No, stop, the pipe is unacceptable.	Yes	No
Is the pipe marked (in accordance with the specification) with identification symbols relating to a specific heat number and coating lot designation? (If unsure, contact the manufacturer.) If No, stop, the pipe is unacceptable.	Yes	No
Do the markings repeat on the pipe on intervals not exceeding 5 ft? If No, stop, the pipe is unacceptable.	Yes	No
Is the steel sheet used to make this pipe free from injurious defects such as blisters, flux, and uncoated spots? If No, stop, the pipe is unacceptable.	Yes	No
Has the steel sheet used in this pipe been sampled in the last 12 months? If No, sample the sheet following the instructions in 1020 Corrugated Metallic-Coated Steel Culvert Pipe, Pipe-Arches and End Sections.	Yes	No
If any pipe is "shop elongated", is the vertical axis is 4 - 6% greater than the nominal diameter? If No, the shop elongated pipe in the shipment is unacceptable.	Yes	No
If any pipe is "shop elongated", does it have a paint mark indicating the top of pipe, and is the mark in the correct position? If No, the shop elongated pipe is unacceptable.	Yes	No
If any pipe is "shop elongated" and the end has been left round to accommodate connections, does it have a mark indicating in.Outside End-Round in. at that end of the pipe? If No, the shop elongated pipe with round end is unacceptable.	Yes	No
If any pipe has "beveled ends", is the beveled end smooth and have the cut edges apparently been covered with two coats of the specified paint? If No, the beveled ends pipe is unacceptable.	Yes	No
Are the "end sections" in accordance with the shape, dimensions and sheet thickness shown on the plans? If No, the end section is unacceptable.	Yes	No
Are the "end sections" integral units or made in sections that may be assembled in place? If No, the end section is unacceptable.	Yes	No
Are "coupling bands" or "bell and spigot joint system" in accordance with Sec 1020.4.6? If No, the coupling band or pipe with a bell and spigot joint system is unacceptable.	Yes	No
Are "special fittings" in accordance with Sec 1020.4.7? If No, the special fitting is unacceptable.	Yes	No

A single-spot test by magnetic or electronic gauge shall be performed, in accordance with this article and ASTM E376, on at least one pipe per lot inspected, to determine the average coating mass (weight). The rate of testing may be reduced at the discretion of the engineer once the Quality Control practices of the manufacturer have been established. This testing may also be performed as one of the last procedures in the inspection process if the engineer chooses.

Is the mass (weight) of the coating (as determined by measuring the thickness of coating) equal to or greater than the specified minimum? (refer to Samples for Chemical Analysis in 1020.2.4) If No, stop, the pipe is unacceptable.	Yes	No
Is the pipe Riveted? If Yes, go to Riveted Pipe.	Yes	No
Is the pipe Helical Lock Seam? If Yes, go to 1020.5.2 Helical Lock Seam.	Yes	No

If you encounter welded pipe, please contact Construction and Materials for guidance.

1020.5.1 Riveted Pipe

The pipe inspected in detail should be the one that appears to have the most instances of poor workmanship and/or materials.

If the pipe is "pipe arch," does it have a longitudinal seam on the corner radius or invert? If Yes, stop, the pipe is unacceptable.	Yes	No
If the pipe is "pipe arch," does it have any wrinkles or kinks in the arch? (This is an indication that the steel has yielded.) If Yes, stop, the pipe is unacceptable.	Yes	No
Are there any missing rivets? If Yes, stop, the pipe is unacceptable.	Yes	No
Are there any rivets that are too small and not supplemented by an adjacent correct size rivet or bolt? If Yes, stop, the pipe is unacceptable.	Yes	No
Are there any rivets that have not been placed in the valley of the corrugation? If Yes, stop, the pipe is unacceptable.	Yes	No
Are there any lap joints which a 1/16 in. wire can be pushed through completely? If Yes, stop, the pipe is unacceptable.	Yes	No
Are there two or more lap joints with gaps greater than ¼ in., regardless of the overall length of pipe? If Yes, stop, the pipe is unacceptable.	Yes	No
Are there more than 2 consecutive rivets, 3 rivets in one can, or 9 rivets in the pipe, regardless of overall length, that are less than twice its diameter from the edge of the sheet? (This applies to the inside and outside of the pipe.) If Yes, stop, the pipe is unacceptable.	Yes	No
For a pipe with a 12 in. diameter, are there less than 6 circumferential rivets? If Yes, stop, the pipe is unacceptable.	Yes	No
For pipe with a diameter greater than 12 in., are there more than two instances of rivet spacing in the circumferential seam greater than 6 in.? If Yes, stop, the pipe is unacceptable.	Yes	No
For pipe with a diameter greater than 12 in., are there any instances of rivet spacing in the circumferential seam greater than 8 in.? If Yes, stop, the pipe is unacceptable.	Yes	No
Are there any deformations from typical shape that are greater than ½ in. from the specified position? (Recommended apparatus: Stiff wire to lay on circumference of pipe over deformation. ½ in. marble or ball bearing to pass under wire.) If Yes, stop, the pipe is unacceptable.	Yes	No
Are there any scrapes or other injuries to the coating that exposes the base metal on the bottom third of the perimeter as installed (or will be installed)? If Yes, stop, the pipe is unacceptable.	Yes	No
Are there any scrapes or other injuries to the coating that exposes the base metal and are longer than 1 in. on the top two thirds of the perimeter as installed (or will be installed)? If Yes, stop, the pipe is unacceptable.	Yes	No
Are there any instances where the expanded head of a rivet is between the two sheets, not holding the inside sheet (this is treated as a missing rivet), and the resulting space between acceptable rivets is greater than 8 in.? If Yes, stop, the pipe is unacceptable.	Yes	No
Is the diameter within the specified tolerances? (Refer to Table 1020.4.11 Diameter Dimensional Tolerances (English) and Table 1020.4.12 Diameter Dimensional Tolerances (Metric)). If No, stop, the pipe is unacceptable.	Yes	No
Is the lap of the longitudinal seam less than specified? (Refer to Table 1020.5.5 Pipe Requirements.) If Yes, stop, the pipe is unacceptable.	Yes	No
Do the corrugations of the pipe have the proper width and height as specified? (Refer to Table 1020.4.8 Pipe Requirements and Table 1020.5.3 Corrugated Metallic-Coated Steel Circular Pipe.) If No, stop, the pipe is unacceptable.	Yes	No
Are there more than 6 rusty rivets in the pipe? (This indicates that the rivet is not galvanized.) If Yes, stop, the pipe is unacceptable.	Yes	No
Are there any loose rivets resulting in unacceptable rivet spacing? 'If Yes, stop, the pipe is unacceptable.	Yes	No
Are there more than 2 defective rivets in a can or more than 1% of the total rivets in the pipe that are defective? (Defective rivets are those that are severely bent or struck off-center or are too small.) If Yes, stop,' the pipe is unacceptable.	Yes	No

Prior to the QA inspection, the fabricator may make the following corrections:

1. Defective rivets may be re-struck or replaced with a correct size rivet or bolt

2. In the case of rivet spacing being too great, additional rivets or bolts may be added

3. A small dent may be hammered out as long as any scrape or other injury created by the hammering is properly re-coated in accordance with the specification

4. A missing rivet may be replaced with a correct size rivet or bolt

5. A small rivet may be replaced with a correct size rivet or bolt

6. A correct rivet or bolt may be placed directly adjacent to a rivet that is too small, or defective, in lieu of replacement

Have you rejected more than 25% of the shipment on the basis of the preceding sections? If Yes, the entire shipment is to be rejected.

Yes

No

1020.5.2 Helical Lock Seam

The pipe inspected in detail should be the one that appears to have the most instances of poor workmanship and/or materials. This inspection also includes inspection of a coupon containing the lock seam.

Are there any visible cracks in the metal of the finished lock seams? If Yes, stop the pipe is unacceptable.	Yes	No
Are there any roller indentations (usually indicative of a seam with excessive interior angularity)? If Yes, stop, the pipe is unacceptable.	Yes	No
Does the lock seam include the proper retaining offset according to specification? (Refer to Figure 1020.5.2.1, Retaining offset measured from Point of Contact to parallel surfaces.) If No, stop, the pipe is unacceptable.	Yes	No

Fig. 1020.5.2.1, Retaining offset measured from Point of Contact to parallel surfaces

Is there excessive interior angularity? Refer to Figure 1020.5.2.2, Excessive interior angularity. If Yes, stop, the pipe is unacceptable.

Yes

No

Fig. 1020.5.2.2, Excessive interior angularity

Is there at least 5/16 in. of lap in the cross section of the lock seam? If No, stop, the pipe is unacceptable.	Yes	No
Is there any loss of metal to metal contact in the lock seam? If Yes, stop, the pipe is unacceptable.	Yes	No
Is the diameter within the specified tolerances? (Refer to Table 1020.4.11 Diameter Dimensional Tolerances (English) and Table 1020.4.12 Diameter Dimensional Tolerances (Metric).) If No, stop, the pipe is unacceptable.	Yes	No
Are there any deformations from typical shape that are greater than ½ in. from the specified position? (Recommended apparatus: Stiff wire to lay on circumference of pipe over deformation. ½ in. marble or ball bearing to pass under wire.) If Yes, stop, the pipe is unacceptable.	Yes	No
Are there any scrapes or other injuries to the coating that exposes the base metal? If Yes, stop, the pipe is unacceptable.	Yes	No
Do the corrugations of the pipe have the proper width and height as specified? (Refer to Table 1020.4.8 Pipe Requirements and Table 1020.5.3 Corrugated Metallic-Coated Steel Circular Pipe.) If No, stop, the pipe is unacceptable.	Yes	No

Prior to the QA inspection, the fabricator may make the following corrections:

1. For scrapes or other injuries, paint may be applied to the exposed area in accordance with the specification

2. A dent may be hammered out as long as any scrape or other injury created by the hammering is properly re-coated in accordance with the specification. (Refer to No. 1, immediately above.)

Have you rejected more than 25% of the shipment on the basis of the preceding sections? If Yes, the entire shipment is to be rejected.

Yes

No

Table 1020.5.3 Corrugated Metallic-Coated or Polymer-Coated Steel Circular Pipe (Lock or Welded Seam), from Std. Plan 725.00

Maximum Allowable Overfill Heights (ft), Measured from the Top of the Pipe to the Surface

Specified Diameter of Pipe (in.)	Minimum Cover (ft.)	Specified Thickness of Coated Steel, in.
		0.064				0.079				0.109				0.138				0.168
		A1	B2	C3	D4	A1	B2	C3	D4	A1	B2	C3	D4	A1	B2	C3	D4	A1	B2	C3	D4
12	1	213	-	-	139	266	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-
15	1	170	-	-	111	212	-	-	156	-	-	-	-	-	-	-	-	-	-	-	-
18	1	142	-	-	93	177	-	-	130	-	-	-	-	-	-	-	-	-	-	-	-
21	1	121	-	-	79	152	-	-	111	-	-	-	-	-	-	-	-	-	-	-	-
24	1	106	-	-	69	133	-	-	97	186	-	-	162	-	-	-	-	-	-	-	-
30	1	85	-	-	55	106	-	-	78	149	-	-	130	-	-	-	-	-	-	-	-
36	1	71	-	-	46	88	-	-	65	124	-	-	108	159	-	-	157	-	-	-	-
42	1	60	-	-	39	76	-	-	55	106	-	-	93	137	-	-	134	167	-	-	-
48	1	53	61	54	34	66	76	68	48	93	107	95	81	119	138	122	118	146	168	150	-
54	1	-	54	48	-	59	68	60	43	82	95	84	72	106	122	109	104	130	150	133	-
60	1	-	48	43	-	-	61	54	39	74	85	76	65	95	110	98	94	117	135	120	-
66	1	-	44	39	-	-	55	49	-	-	77	69	59	87	100	89	85	106	122	109	-
72	1	-	40	36	-	-	51	45	-	-	71	63	54	79	92	81	78	97	112	100	-
78	1	-	37	33	-	-	47	41	-	-	65	58	50	-	84	75	72	86	103	92	-
84	1	-	34	31	-	-	43	38	-	-	61	54	-	-	78	70	69	75	96	85	-
90	1	-	32	29	-	-	40	36	-	-	57	50	-	-	73	65	62	-	90	80	-
96	1	-	-	-	-	-	38	34	-	-	53	47	-	-	69	61	58	-	84	75	-
102	2	-	-	-	-	-	36	32	-	-	50	44	-	-	64	57	-	-	79	70	-
108	2	-	-	-	-	-	-	-	-	-	47	42	-	-	61	54	-	-	75	66	-
114	2	-	-	-	-	-	-	-	-	-	45	40	-	-	58	51	-	-	71	63	-
120	2	-	-	-	-	-	-	-	-	-	42	38	-	-	55	49	-	-	67	60	-
126	2	-	-	-	-	-	-	-	-	-	-	-	-	-	52	46	-	-	64	57	-
132	2	-	-	-	-	-	-	-	-	-	-	-	-	-	50	44	-	-	61	54	-
138	2	-	-	-	-	-	-	-	-	-	-	-	-	-	48	42	-	-	58	52	-
144	2	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	-	56	50	-
1 A = 2 2/3 in. x ½ in. corrugations
2 B = 3 in. x 1 in. corrugations
3 C = 5 in. x 1 in. corrugations
4 D = 3/4 in. x 3/4 in. x 7 ½ in. spiral rib
Note: It is the responsibility of the inspector to confirm that this table is in accordance with the Standard Plans. Refer to Std Plan 725.00

Table 1020.5.4 Corrugated Metallic-Coated Steel Circular Pipe (Riveted, Bolted or Spot-Welded Seam), from Std. Plan 725.00

Maximum Allowable Overfill Heights (ft)), Measured from the Top of the Pipe to the Surface

Specified Diameter of Pipe (in.)	Minimum Cover (ft.)	Specified Thickness of Coated Steel, in.
		0.064		0.079		0.109		0.138		0.168
		A1	B2	A1	B2	A1	B2	A1	B2	A1	B2
12	1	92	-	101	-	-	-	-	-	-	-
15	1	74	-	80	-	-	-	-	-	-	-
18	1	61	-	67	-	-	-	-	-	-	-
21	1	53	-	57	-	-	-	-	-	-	-
24	1	46	-	50	-	65	-	-	-	-	-
30	1	37	-	40	-	52	-	-	-	-	-
36	1	30	-	33	-	43	-	45	-	-	-
42	1	26	-	28	-	37	-	38	-	40	-
48	1	23	39	25	49	32	73	34	88	35	98
54	1	-	35	22	44	28	65	30	78	31	87
60	1	-	31	-	39	26	58	27	70	28	78
66	1	-	28	-	36	-	53	24	64	25	71
72	1	-	26	-	33	-	49	22	58	23	65
78	1	-	24	-	30	-	45	-	54	21	60
84	1	-	22	-	28	-	42	-	50	20	46
90	1	-	21	-	26	-	39	-	47	-	52
96	1	-	-	-	24	-	36	-	44	-	49
102	2	-	-	-	23	-	34	-	41	-	46
108	2	-	-	-	-	-	32	-	39	-	43
114	2	-	-	-	-	-	30	-	37	-	41
120	2	-	-	-	-	-	29	-	35	-	39
126	2	-	-	-	-	-	-	-	33	-	37
132	2	-	-	-	-	-	-	-	32	-	35
138	2	-	-	-	-	-	-	-	30	-	34
144	2	-	-	-	-	-	-	-	-	-	32
1 A = 2 2/3 in. x ½ in. corrugations
2 B = 3 in. x 1 in. corrugations
Note: It is the responsibility of the inspector to confirm that this table is in accordance with the Standard Plans. Refer to Std Plan 725.00.