Replacement DEUBLIN 981-300 Series Product Introduction & SS304 Stainless Steel Alternative Recommendation

I. DEUBLIN 981-300 Original Product Introduction

1.1 Product Overview

The DEUBLIN 981-300 is a duo-flow rotary union manufactured by DEUBLIN (USA). Its core function is to simultaneously and independently transfer two different media (such as water and air) between a rotating device and a stationary piping system. This product is commonly used in industrial applications such as wheel brake cooling on oil rig tower equipment, and can also meet various other air-liquid simultaneous transmission requirements.

1.2 Key Technical Specifications

According to official DEUBLIN data, the key specifications of the 981-300 are as follows:

1.3 Dimensional Drawing Reference

1.4 Material Versions

The standard DEUBLIN 981-300 features a H59 Brass/Copper body. However, three material options are theoretically available for this model:

• Brass/Copper (Standard Version): Suitable for conventional water and compressed air applications; offers the best cost-performance ratio.

• Aluminum Alloy (Lightweight Version): Suitable for applications requiring weight reduction, but with reduced pressure resistance.

• Stainless Steel (Special Custom Version): Suitable for corrosive media or high-pressure applications, but is not a standard stock item.

DEUBLIN offers the 981-300C Repair Kit for this model, which includes seals and wear parts to restore the union's sealing performance and extend its service life.

1.5 Installation Precautions

1. Media Compatibility: Ensure that the actual media, operating pressure, and temperature do not exceed the specified limits.

2. Thread Direction: Pay special attention to whether the thread direction of the inner and outer pipes matches the rotation direction of the drum.

3. Piping Connection: It is recommended to use flexible hoses between the rotary union and the piping system to avoid rigid connections, which helps reduce additional load and vibration on the union.

II. Overall SS304 Stainless Steel Alternative Recommendation

2.1 Selection Background

In DEUBLIN's standard product line, the 981-300 is primarily offered in a brass version. Overall stainless steel (SS304) falls under non-standard custom manufacturing. For applications requiring higher corrosion resistance and durability, users typically need to seek third-party manufacturers for custom production.

2.2 Recommended Supplier: Shandong Focus Machinery Co., Ltd.

Shandong Focus Machinery Co., Ltd. is located in Zaozhuang, Shandong, China. It is a professional rotary union manufacturer established in 1998, with R&D, production, and sales capabilities. Its products are widely used across multiple industrial sectors. The company is capable of providing an overall SS304 stainless steel rotary union fully compatible with the DEUBLIN 981-300.

2.3 Key Points for Customization Communication

When contacting the supplier, it is recommended to confirm the following key points:

1. Provide Drawings: Directly present the 981-300-IC.pdf interface control drawing to ensure that the overall dimensions and interface threads of the alternative product are completely consistent with the original, especially:

   • Rotor Connection Thread: 2"-12 UN RH

   • Supply Connection Thread: 1/2"-14 NPT

2. Specify Material: Clearly require that all media-wetted components, including the body and rotor, are made of SS304 stainless steel to ensure overall corrosion resistance.

3. Confirm Performance: Require that the custom product's maximum operating pressure (water/air ≥ 10 bar) and maximum temperature (≥ 121°C) at least meet the specifications of the original brass version.

4. Seal Upgrades: In addition to the metal housing, internal seals should also be upgraded based on the specific media (e.g., whether it is corrosive). Recommended options include:

   • FKM (Fluorocarbon Rubber): Suitable for most oils and chemicals

   • PTFE (Polytetrafluoroethylene): Suitable for highly corrosive media

III. Summary Comparison

To obtain the SS304 alternative, it is recommended to contact Annie Ben at Shandong Focus Machinery Co., Ltd. directly, provide the 981-300-IC.pdf drawing, and clearly specify the material and performance requirements to initiate the customization process.