Extension rods are made by hollow drill steels; there are two shapes of extension rods, round type and hexagonal type. This hollow hole are usually named flushing hole, used for transmitting water or air during drilling. And the threads can be used for connecting couplings, shanks, couplings or bits. 
Usually for extension rods, there are R22, R25, R28, R32, R38, T38, T45, T51, ST58, T60 threads, and different lengths of rods are available from 600mm to 6400mm usually.
(1)Steel grade: Male-Male Rod, MF Rod
(2) Thread: R22, R25, R28, R32, R38, T38, T45, T51, 
(3) Rod size: hex. 22mm, hex. 25mm, hex. 28mm, hex. 32mm, hex. 35mm, dia. 39mm, dia. 46mm. dia. 52mm
(3)Length: 0.4m-6m
(4)Package: in wooden case or in bundles. 
(5)Productivity: 20000MT / month

 

Q: Are you a manufacturer or trading company?

 A: We are a specialized manufacturer.

 

Q: What are your main products, and used for?

 A: Our products rock drilling tools , mining tools, TBM cutters , anchor bolts , DTH bits & hammers, mining carbide and coal mining tools.

 

Q: How about the delivery terms?

 A: 1. Payment: T/T, Western Union, Paypal, 30% deposit in advance and rest before delivery. 

      2. Min. order quantity: 1 piece.

      3. Transportation: By DHL/TNT/Fedex express, air, sea.

 

Q: How about discount?

 A: Price is based on products and order quantity.

Q: Do you accept sample order?

 A: Yes sure, please contact us for details.

Q: How about your after-sales service?

 A: As a manufacturer, we offer promote technology support for all problems and questions. Besides, we accept goods return or replace for quality problem.

Q: Where is your factory located in?

A: Our factory is located in Shandong province, China.

Q: How does your company control the quality?

A: Quality first. In order to guarantee high quality for our products, TY always makes a serious inspection for all products and raw materials in strict procedure.