Which pump models does this lock nut fit?

It fits the Kerr JT7020, KA-3500PT, KT-3350PT, KT-3400PT, T-35, T50 and T50-PT models.

What does the "1"-8 nylon" in the name mean?

It describes the thread and locking feature: a 1-inch nominal diameter with 8 threads per inch (1"-8), and a nylon insert that resists loosening under vibration.

What part number is this cross-referenced to?

It is an aftermarket replacement cross-referenced to Kerr SKU KA-270; the brand and part number are used only for identification and do not indicate OEM manufacture.

Lock Nut Piston Extension Rod 1"-8 Nylon

Lock Nut Piston Extension Rod 1"-8 Nylon — Piston aftermarket replacement part

This Lock Nut is a 1"-8 nylon-insert lock nut used on the piston extension rod of reciprocating pumps, where it secures and retains the threaded rod connection against loosening under the pump's reciprocating loads. It fits a range of Kerr horizontal directional drilling (HDD) mud pumps, including the KA-3500PT, KT-3350PT, KT-3400PT, JT7020, T-35, T50 and T50-PT. It weighs about 0.5 lb and is supplied as an aftermarket replacement part, cross-referenced to Kerr SKU KA-270 for identification.

What it is

A pump piston transmits force from the power end to the pumped fluid inside the cylinder liner. It carries the sealing element and reciprocates within the liner bore on every stroke.

Pump compatibility

JT7020
KA-3500PT
KT-3350PT
KT-3400PT
T-35
T50
T50-PT

Specifications

Property	Value
Weight	0.50 lb (≈ 0.23 kg, converted)
Width	（无）
Height	（无）
Depth	（无）

Manufacturer technical notes

Lock Nut Piston Extension Rod 1"-8 Nylon (SKU KA-270), forged from ASTM A193 B7 alloy steel with nylon insert anti-loosening design, API 7K-compliant for mud pumps (F series/F1300), tensile strength ≥1050MPa, thread class UN 1A/2B, NACE MR0175 corrosion-resistant, operational stability -20°C~+120°C, 40% vibration resistance enhancement under dynamic loads.

Verbatim from the Dongli product page on dlhddrilling.com.

Replacement / interchange

Aftermarket replacement cross-referencing Kerr KA-270.

FAQ

Which pump models does this lock nut fit?: It fits the Kerr JT7020, KA-3500PT, KT-3350PT, KT-3400PT, T-35, T50 and T50-PT models.
What does the "1"-8 nylon" in the name mean?: It describes the thread and locking feature: a 1-inch nominal diameter with 8 threads per inch (1"-8), and a nylon insert that resists loosening under vibration.
What part number is this cross-referenced to?: It is an aftermarket replacement cross-referenced to Kerr SKU KA-270; the brand and part number are used only for identification and do not indicate OEM manufacture.

Related parts

See all Piston →

All brand names, model numbers and part numbers are used for identification and cross-reference only and do not imply original-equipment manufacture. This is an aftermarket replacement part.

Need a quote or part lookup? Contact our team.