Integrated Filter/Regulators MD4 Series Installation & Operating Instructions

Overview

ROSS Controls, founded in 1921 with over 100 years of leadership in fluid power, offers the Modular Integrated Filter/Regulator MD4 Series as a combined filtration and pressure regulation unit in a single compact housing. By integrating a 5-micron polyethylene filter element with a piston-type regulator in one body, this product reduces installation space, simplifies piping, and lowers the cost of a complete air preparation system compared to separate filter and regulator components.

The MD4 Integrated Filter/Regulator delivers flows up to 230 scfm through port sizes of 3/8, 1/2, and 3/4 inch, with adjustable outlet pressure up to 175 psig (12 bar). The filter section removes particulate down to 5-micron and collects liquids in the bowl, which can be drained manually or automatically. If pressure differential across the filter element reaches 8 psid, the element must be replaced.

When adjusting pressure, always reset from a pressure lower than the final desired setting. For example, to set 50 psi, first lower to 30 psi then increase to 50 psi. This approach ensures accurate pressure setting. For questions, contact ROSS at 1-800-GET-ROSS or visit www.rosscontrols.com.

Key Features

Combined Filtration and Regulation in One Unit

The integrated design eliminates the need for a separate filter body and filter-to-regulator connection fitting. Air enters the integrated unit, passes through the 5-micron filter element removing particulate and separating liquids, and then flows through the piston regulator which sets and maintains downstream pressure. The bowl collects separated liquids for periodic draining — manually via the drain knob or automatically via the auto-drain option.

Piston Regulator for Stable High-Pressure Output

The piston-type regulator construction provides excellent pressure stability at higher outlet pressures, with a bonnet option available for 0 to 175 psig (0 to 12 bar) range. Standard construction uses a nylon bonnet; an aluminum bonnet is available for the full 0 to 175 psig spring range. The pressure adjustment key is removable to prevent tampering, and panel mounting requires a 2.05 inch (52.1 mm) cutout.

Automatic and Manual Drain Options

The MD4 IFR is available with both manual drain and automatic drain configurations. The automatic drain uses a float mechanism that opens when bowl liquid reaches a threshold, draining accumulated liquids continuously. Flexible tubing (3/16 inch ID) can be connected to the drain stem to route discharge away from the installation. The drain knob position controls drain sensitivity. If the pressure differential reaches 8 psid, the element must be replaced.

Technical Specifications

Construction: Filter – 5-micron polyethylene fiber; Regulator – Piston
Maximum Flow: 230 scfm
Port Sizes: 3/8, 1/2, and 3/4 inch
Outlet Pressure: Adjustable up to 175 psig (12 bar)
Polycarbonate Bowl Temperature: 40° to 125°F (4° to 52°C)
Metal Bowl Temperature: 40° to 175°F (4° to 80°C)
Inlet Pressure (Automatic drain, polycarbonate bowl): Up to 150 psig (10 bar)
Inlet Pressure (Automatic drain, metal bowl): Up to 200 psig (14 bar)
Inlet Pressure (Manual drain, polycarbonate bowl): 0 to 150 psig (0 to 10 bar)
Inlet Pressure (Manual drain, metal bowl): 0 to 200 psig (0 to 14 bar)
Filter Element: 5-micron rated polyethylene; 40-micron optional
Filter Element Replacement Differential: Replace when pressure drop reaches 8 psid
Pressure Adjustment Locking Key: Removable
Panel Mounting: 2.05 inch (52.1 mm) hole required
Body: Zinc; Cap Color: Black; Seals: Nitrile; Valve: Brass
Bowl: Polycarbonate with steel shatterguard, or aluminum with clear sight glass
Bonnet: Nylon standard; aluminum optional
Modular Connection Torque: 30-40 in-lbs (R-A118-105 or R-A118-105M)

Applications

Space-Constrained Air Preparation Stations

When machine design or retrofit constraints limit available space for an air preparation panel, the integrated filter/regulator provides full filtration and pressure regulation in the footprint of a single unit. This is especially valuable in compact automation cells, robotic workstations, and modular machine modules where multiple separate FRL components would be difficult to accommodate.

MD4 Modular FRL Systems

As the filter/regulator module of the ROSS MD4 platform, the integrated filter/regulator pairs directly with the MD4 lubricator (SS-L022) and other MD4 accessories to create complete modular FRL assemblies. The modular port bracket interface simplifies assembly and allows filter element and bowl service without disconnecting the air preparation panel from the machine.

Safety and Compliance Standards

Depressurize and lock out air pressure before any service. Do not exceed inlet pressure ratings for each bowl type. Replace filter elements when pressure differential reaches 8 psid — do not attempt to clean standard polyethylene elements (sintered bronze elements may be cleaned by soaking in soap and water then reverse-blowing with compressed air). Use correct torque values: Valve Cap 55-65 in-lbs; Dome 190-210 in-lbs; Lower Baffle 5 in-lbs maximum; Drain Nut 5-15 in-lbs; Bowl Retaining Ring 30-50 in-lbs.

Installation and Setup Guide

Installation Steps

Step 1: Depressurize and lock out air pressure.
Step 2: Ensure upstream pipes are free of dirt and liquids.
Step 3: Install with air flow in the direction of the arrow on the head.
Step 4: Install vertically with drain mechanism at the bottom.
Step 5: Install and close gauge ports — pressure gauge or pipe plugs must be installed before operating.
Step 6: Install upstream of any lubricators in the air line.
Step 7: For modular clamp installation, torque connection screws 30-40 in-lbs.
Step 8: Set outlet pressure from a lower value up to the desired setpoint.
Step 9: For auto-drain: connect 3/16 inch ID flexible tubing to drain stem for discharge routing.
Step 10: Monitor filter pressure differential; replace filter element at 8 psid.

Why Choose ROSS Controls

ROSS Controls, founded in 1921 with over 100 years of leadership in fluid power, offers complete air preparation solutions, including integrated filter/regulator products that reduce system cost, installation complexity, and maintenance requirements. Contact ROSS at 1-800-GET-ROSS or www.rosscontrols.com for specifications and distributor information.

Download This Document

PDF download: https://ross-admin-global-us-east.s3.amazonaws.com/production/uploads/document_language_file/file/207/Integrated_Filter_Regulator_Modular_MD4_Series_SS-IFR006.pdf

Frequently Asked Questions

Q: When should the filter element be replaced?

A: Replace the filter element when the pressure differential reaches 8 psid. Do not clean standard polyethylene elements; replace them. Sintered bronze elements may be cleaned by soaking in soap and water and reverse-blowing with compressed air.

Q: What is the outlet pressure range?

A: Adjustable up to 175 psig (12 bar) with the aluminum bonnet spring option.

Q: What is the maximum inlet pressure?

A: Up to 150 psig for polycarbonate bowl models; up to 200 psig for metal bowl models.

Q: How do I correctly set outlet pressure?

A: Always increase from a pressure lower than the desired setpoint. For example, to set 50 psi: lower to 30 psi, then increase to 50 psi.

Q: What filter rating is standard?

A: 5-micron rated polyethylene. A 40-micron element is available as an option.

Q: What is the torque for the bowl retaining ring?

A: 30-50 in-lbs. When fully seated, there should be a 0.020-0.040 inch gap between the bowl retaining ring and the head.

Q: What is the maximum flow rate?

A: Up to 230 scfm.

Q: How does the auto-drain work?

A: The automatic drain uses a float mechanism that opens when bowl liquid accumulates, draining it automatically. A 3/16-inch ID flexible tube can be connected to the drain stem to route discharge to a collection point.