API spec drill collar used in coal mine with petrochina quality

api spec drill collar, 1.standard:API 7-1, 2.OD:79.4mm-279.4mm, 3.Certifactes: ISO ,API 7-1, 4.Moq: 25 tons - details see: https://www.machineto.com/api-spec-drill-collar-used-in-coal-mine-with-petrochina-quality-10317641

Place of Origin:Shaanxi China (Mainland)	Brand Name:Chang Gong	Model Number:4"-11"	Type:Drill Collar
Machine Type:Drilling Tool	Certification:API	Material:Carbon Steel	Processing Type:Forging
Use:Well Drilling

api spec drill collar

1.standard:API7-1
2.OD:79.4mm-279.4mm
3.factory directly delivery
4.Moq: 25 tons

5.Certificates : ISO ,API 7-1 ,api 5dp .

We are "Petrochina " subcompany

Descriptions:

Drill collars is one of the most important product of hexin oil drillings which mainly used to provide bit weight to drill so that drill pipe is in tension. Especially drill collar can keep drill bit centralized and hole track by large rigidity. GANG GONGbrand drill collars are manufactured strictly from API Spec7-1 standard.

Type	OD(mm)	ID(mm)	L(m) ±152.4mm d	DF(mm) ±0.4
NC23-31	79.4	31.8	9.14	76.2
NC26-35	88.9	38.1	9.14	82.9
NC31-41	104.8	50.8	9.14or9.45	100.4
NC35-47	120.6	50.8	9.14or9.45	114.7
NC38-50	127	57.2	9.14or9.45	121
NC44-60	152.4	57.2	9.14or9.45	144.5
NC44-60	152.4	71.4	9.14or9.45	144.5
NC46-62	158.8	57.2	9.14or9.45	149.2
NC46-62	158.8	71.4	9.14or9.45	150
NC46-65	165.1	57.2	9.14or9.45	154.8
NC46-65	165.1	71.4	9.14or9.45	154.8
NC46-67	171.4	57.2	9.14or9.45	159.5
NC50-70	177.8	57.2	9.14or9.45	164.7
NC50-70	177.8	71.4	9.14or9.45	164.7
NC50-72	184.2	71.4	9.14or9.45	169.5
NC56-77	196.8	71.4	9.14or9.45	185.3
NC56-80	203.2	71.4	9.14or9.45	190.1
6-5/8REG	209.6	71.4	9.14or9.45	195.6
NC61-90	228.6	71.4	9.14or9.45	212.7
7-5/8REG	241.3	76.2	9.14or9.45	223.8
NC70-97	247.6	76.2	9.14or9.45	232.6
NC70-100	254	76.2	9.14or9.45	237.3
8-5/8REG	279.4	76.2	9.14or9.45	266.7
NC50-67	171.5	71.4	9.14or9.45	159.5