MM Extension Rod
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 button bits.
Hexagonal cross sections rods are more rigid, heavier and transfer energy more efficiently, while increasing flushing.
Round rods are generally lighter than hexagonal rods and are normally used in extension drilling applications.With the longer steel tending to be larger in diameter, conventional extension steel is characterized by a duplicate thread on each end of the steel.
Suitable Bits Thread
Drilling Hole Range
R25, R28, R32
R28, R32, R38
R28, R32, R38, T38
1 37/64～2 1/2
R32, R38, T38
R32, R38, T38
1 3/4～2 1/2
R38, T38, T45
2 1/4～3 1/2
T38, T45, T51
How to order?
Length + Thread + Body Shape and Diameter
1. Reliable and guaranteed quality.
2. Very competitive price
3. Wide range of products to meet the different markets' customers
4. Develop new according to the different market
5. OEM IS AVAILABLE
1. Can I expect a quality products?
A: Yes. mature production technology ensuring the quality satisfy international request.
2. How to check the product are the exact one you want?
A: If possible, please attach one reference picture to avoid any misunderstanding or any links from ourwebsite for a better understanding.
3. How to make sure the quality?
More than 40 Years engineer to make sure the quality, 100% inspection
4. Fast delivery time:
A: Usually it takes 25 days for production.only 3 or 5 days if we have stock of your request size.
5. Competitive price:
A: KINGDRILLING factory can supply you the lowest price due to direct sale to customers without distributor!
6. Product feature
Kingdrilling DTH tools are forged by advanced electron-hydraulic forging hammer, and harness process is managed by multipurpose furnace heat treatment.