4 mm In-Line Check Valve with Flow Control

What This Check Valve Does

This is a brass in-line check valve with four-level flow control, built into an oil lubrication line between the pump or divider and the points being lubricated. It passes oil in one direction only: forward flow continues, reverse flow is blocked. The four-level control lets you set how much oil passes at each point, from Level 1, the lowest, up to the highest level.

Fit it downstream of the pump or divider so backflow cannot drain the line or starve another branch. Coarse debris upstream is a strainer’s job, so protect the valve with a y-type strainer.

Declared Specifications

How the Valve Works

Inside the body, the check element lifts when oil flows forward and seats against the passage when flow tries to reverse, so the line holds its direction of travel. The flow-control setting sits in the same path and meters how much oil passes through at each setting. The four levels are a qualitative series: no numeric flow figures are declared for them, so match the level to the demand of the point downstream and confirm when ordering if the duty is unusual.

Because reverse flow is blocked, the arrow on the body must match the direction the oil actually travels in the line. Fit it the wrong way and the line will not pass oil at all.

Choosing a Flow Level

Level selection follows what sits downstream. A single bearing point fed by a push-up lubrication fitting is a typical downstream consumer; its demand sets the level you want at the valve. Start at the lowest level and raise it one step at a time while watching the lubrication point, so you can see when oil arrives and stop there.

Where one valve feeds several points, balance the levels across those points instead of turning one branch to its maximum. Uneven settings push oil to the easiest path. When the application is unclear, confirm the intended level and duty when ordering.

Installation

Check the arrow on the body first, then fit the valve so that arrow points the way oil moves in the line. Insert or retain the 4 mm tube according to the retention method, which is a confirm-when-ordering item. Nylon, aluminum and copper tube are all declared for this valve; see the tubing range for lubrication lines when matching tube to the rest of the circuit.

Run the line at low pressure first and check for weeping at both connections. After the first temperature cycles, re-check the joints and the setting, since tube movement can loosen a fitting.

What Is Supplied

One valve is supplied. Retention inserts or seals, where the chosen method needs them, are confirm-when-ordering items rather than assumed parts. Related brass line parts appear on the tee coupling page, and filters for the same circuit are listed under lubrication filters. For specifications and a quotation, contact us for a quote.

Frequently Asked Questions

What does this valve do?

It passes oil one way and blocks reverse flow, with four levels of flow control.

What does 4 mm mean?

It is the tube outside diameter, not the bore and not a thread size.

Which tube materials?

Nylon, aluminum and copper tube are declared for this valve.

How do I pick a level?

Start at the lowest level, watch the point downstream, and raise it as needed.

What is the cracking pressure?

It is not separately declared; confirm when ordering.

What if it is installed backwards?

Reverse flow is blocked, so the arrow must match the line direction.

Can it carry air or water?

It is declared for oil-based media; confirm other fluids when ordering.

Does it need a sealant?

It depends on the retention method; confirm when ordering.

How many are supplied?

One valve; see What Is Supplied above.

How do I get specifications and a quotation?

IsoHiTech Lubrication Systems, founded in 2023, engineering since 2006, builds and supports every unit. Email inquiry@isohitech.com for specifications and a quotation.

For oil line filtration and tubing to match, request a quote.