Malleable Iron Pipe Fitting

Maito Lead delivers high-quality, fully traceable, application-matched fittings that turn “reliable connection” into a repeatable outcome—project after project.

Threaded Malleable Iron Fittings

Challenge We Solve

In any piping system, long-term leak-tight connections depend on three things: product quality, application fit, and proper installation. If any one fails, you risk leaks, downtime, and higher maintenance costs.

Our Commitment

Maito Lead delivers high-quality, fully traceable, application-matched fittings that turn “reliable connection” into a repeatable outcome—project after project.

Overview

Our malleable iron threaded fittings—core PVF components—span elbows, tees, crosses, unions, couplings, caps, plugs, reducers, bushings, locknuts, and more, with black or hot-dip galvanized (HDG) finishes and BSPT/BSPP/NPT threads.

Types of Malleable Iron Pipe Fitting

Galvanized Malleable Iron Reducing Tee 25×20×20

High-quality malleable iron reducing tee for joining different pipe sizes; black or HDG finish, BSP/NPT threads for durable, easy installation.

ISO 7-1 BSP Malleable Iron Square Plug

ISO 7-1 BSP threaded square plug in black or galvanized finish; corrosion-resistant end closure with FM/UL compliance.

Black Malleable Iron Reducing Elbow (BSP/NPT 90°)

90° reducing elbow for tight spaces and size transitions; durable black or galvanized finish for plumbing, gas, fire, and industrial use.

Production Process and Technology

The production process of malleable cast iron products is divided into 10 major processes: molding - melting - pouring - annealing - polishing - correction - grinding - edge marking - galvanizing - threading

1. Molding

There are many casting methods, which are usually divided into two categories: sand casting and special casting. Our malleable cast iron pipe fittings are produced using the sand casting method.

2. Melting

The smelting process is all carried out in electric furnaces. Firstly, it avoids the high air pollution caused by the combustion of fuel in traditional cupolas, which meets the requirements of environmental protection. Secondly, it makes the material heated evenly during the melting process, avoiding casting defects caused by overcooling or overheating of the melt during the pouring process.

3. Pouring

The molten metal material is poured into the mold and the casting is obtained after cooling and solidification.

4. Annealing

The metal is slowly heated to a certain temperature, kept for a sufficient time, and then cooled at an appropriate rate. The purpose is to reduce hardness, improve machinability; eliminate residual stress, stabilize dimensions, reduce deformation and crack tendency; refine grains, adjust structure, and eliminate structural defects.

5. Polishing

The castings obtained after the sand removal treatment must first undergo surface polishing to obtain a semi-finished product with a smooth surface. Jianzhi uses a centrifugal polishing machine and steel balls as polishing materials. In the centrifugal polishing machine, the steel balls and the castings are repeatedly ground to smooth the appearance.

6. Correction

After polishing, if the roundness does not meet the requirements or the surface shape does not meet the requirements, the castings must go through a correction process to make the shape meet the requirements.

7. Grinding

After the casting is corrected, the larger slag remaining on the surface after polishing should be removed through the grinding process to achieve a beautiful appearance.

8. Edge Marking

Since casting molds are usually designed to produce multiple batches of parts per mold, castings usually have flash caused by pouring from the pouring gate and connecting channels designed for the casting mold. In the trimming process, these flashes on the inner and outer surfaces of the casting are removed by machining.

9. Galvanizing

The pipe fittings are galvanized first and then threaded. This avoids thread size deviation caused by the galvanized layer and ensures smooth installation.

10. Threading

Threading refers to machining threads of different national standards on the castings according to specific requirements.

Product Advantage

Malleable iron construction delivers pressure-rated strength and impact/vibration toughness, while precision threads ensure tight, repeatable seals. HDG finish extends service life in humid or lightly corrosive environments, and standardized dimensions speed installation and fit common pipe, valve, and instrument interfaces.

PSI

Max working pressure

μm

Average Zinc Thickness

MPa

Tensile Strength

Elongation

Applications of Malleable Iron Pipe Fitting

Fire protection systems (sprinkler, hydrant, standpipe).

Leak-tight threaded joints handle pressure and elevated temperatures in code-driven networks. HDG options improve corrosion resistance; FM/UL availability supports compliance and predictable maintenance.

Water systems (treatment, distribution, plant utilities).

Durable, economical connections deliver reliable sealing through vibration and thermal cycling. Black/HDG finishes and BSPT/BSPP/NPT threads ensure interchangeability across sites.

HVAC systems (chilled/hot water, AHU/FCU, cooling towers).

Standardized dimensions enable fast, clean tie-ins and retrofits in equipment rooms and risers. Precision threads maintain leak-tightness over service life, reducing downtime and maintenance cost.

Why Choose Maito Lead

Choose Maito Lead for a one-stop PVF portfolio. Our products are specified on code-driven, landmark projects such as Beijing Daxing International Airport and Shanghai Financial Center, as well as major developments across the Middle East and Africa.

Get Touch With Us

CONTACT INFO

+86-130-1137-4563

sales@maitoleadfitting.com / inquiry@maitoleadfitting.com

+8618833207623

Room 914, Xintiandi Building, No. 349 Nanjing Road, Nankai District, Tianjin