Drill Stem Subs Type A/B/C/D | API 7 – DEENPU | API Wellhead & Downhole Equipment Manufacturer

Name: Drill Stem Subs Type A/B/C/D
Brand: DEENPU
SKU: DNP-DS-103
Availability: InStock

DEENPU Drill Stem Subs — API 7 Types A / B / C / D

API 7

Home › Drilling Tubulars & Drill Stem Tools › Drill Stem Subs Type A/B/C/D

Product Overview

DEENPU manufactures all four API 7 types of drill stem subs: Type A (straight OD), Type B (reduced section), Type C (swivel sub) and Type D (lift sub) — with box/pin combinations on either end. Product classes include kelly subs, tool joint subs, crossover subs, drill collar subs, bit subs, swivel subs and lift subs.

Mechanical properties conform to the same standards as drill collars (AISI 4145H modified class). Each sub is marked in a recess on the OD with the API license number, inside diameter and connection style at each end. Rotary shoulder connections cover NC 23-31 to NC 70-100, 2 3/8″ Reg to 8 5/8″ Reg and 5 1/2″ / 6 5/8″ FH.

Key Features

API 7 Types A, B, C, D — all box/pin combinations
AISI 4145H modified, drill collar grade properties
Connections NC 23-31 to NC 70-100, 2 3/8″–8 5/8″ Reg, 5 1/2″/6 5/8″ FH
API-marked in recess: license number, ID, connection style
Any special connection on request

Technical Specifications

Types	A straight OD / B reduced / C swivel / D lift
Classes	Kelly, tool joint, crossover, DC, bit, swivel, lift subs
Material	AISI 4145H modified class
Marking	API license no. + ID + connections in recess
Connections	NC 23-31 to NC 70-100, 2 3/8″–8 5/8″ Reg, FH

Dimensions & Technical Data

Drill stem subs dimensions table — API 7 types, connection sizes NC 23-31 to NC 70-100

Drill stem sub dimensions — API 7 types and connections

Quality & Testing

Every DEENPU Drill Stem Subs Type A/B/C/D is manufactured under our API-compliant quality system: raw material traceability, 100% dimensional inspection, hydrostatic pressure testing and hardness verification before packing. Material certificates, inspection reports and API documentation are provided with shipment on request.

Applications

BHA connection crossovers
Kelly / swivel / top drive make-up
Bit and stabilizer connections
Lift subs for string handling

Frequently Asked Questions

Q: What is the difference between Type A and Type B subs?

A: Type A has a straight OD the full length; Type B has a reduced section (smaller OD) in the middle — used where smaller OD is needed, e.g. under swivels.

Q: Can you make special (non-API) connections?

A: Yes — extra hole, special bevel and other connections can be manufactured to drawing.